[Federal Register: January 23, 2004 (Volume 69, Number 15)]
[Rules and Regulations]
[Page 3240-3257]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr23ja04-6]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 180
[OPP-2003-0373; FRL-7342-1]
Sulfuryl Fluoride; Pesticide Tolerance
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This regulation establishes tolerances for residues of
sulfuryl fluoride and inorganic fluoride from postharvest fumigation
uses of sulfuryl fluoride in or on stored commodities. Dow AgroScience
LLC requested these tolerances under the Federal Food, Drug, and
Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of
1996 (FQPA). This action reflects the first food use on sulfuryl
fluoride in the United States. Sulfuryl fluoride has been registered
for fumigation of structures for termites under the brand name Vikane
for many years. Sulfuryl fluoride is considered to be a methyl bromide
replacement for some of these post-harvest fumigation uses. Under the
Profume product label, grain processing facilities and stored cereal
grains, dried fruits and tree nuts will be fumigated at a maximum use
rate of 1,500 ounces/hours/1,000 ft\3\ (1,500 milligrams/hours/liter
(mg/hr/L) or 200 mg-hr/L under vacuum conditions. Commodities treated
with Profume must be aerated for at least 24 hours before entering
commerce.
DATES: This regulation is effective January 23, 2004. Objections and
requests for hearings, identified by docket ID number OPP-2003-0373,
must be received on or before March 23, 2004.
ADDRESSES: Written objections and hearing requests may be submitted
electronically, by mail, or through hand delivery/courier. Follow the
detailed instructions as provided in Unit VI. of the SUPPLEMENTARY
INFORMATION.
FOR FURTHER INFORMATION CONTACT: Dennis McNeilly, Registration Division
(7505C), Office of Pesticide Programs, Environmental Protection Agency,
1200 Pennsylvania Ave., NW.,Washington, DC 20460-0001; telephone
number: (703) 308-6742; e-mail address: mcneilly.dennis@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. Does this Action Apply to Me?
You may be potentially affected by this action if you are an
agricultural producer, food manufacturer, or pesticide manufacturer.
Potentially affected entities may include, but are not limited to:
[sbull] Crop production (NAICS 111), e.g., agricultural workers;
greenhouse, nursery, and floriculture workers; farmers.
[sbull] Animal production (NAICS 112), e.g., cattle ranchers and
farmers, dairy cattle farmers, livestock farmers.
[sbull] Food manufacturing (NAICS 311), e.g., agricultural workers;
farmers; greenhouse, nursery, and floriculture workers; ranchers;
pesticide applicators.
[sbull] Pesticide manufacturing (NAICS 32532), e.g., agricultural
workers; commercial applicators; farmers; greenhouse, nursery, and
floriculture workers; residential users.
[[Page 3241]]
This listing is not intended to be exhaustive, but rather provides
a guide for readers regarding entities likely to be affected by this
action. Other types of entities not listed in this unit could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether this action might apply to certain entities. If you have any
questions regarding the applicability of this action to a particular
entity, consult the person listed under FOR FURTHER INFORMATION
CONTACT.
B. How Can I Get Copies of this Document and Other Related Information?
1. Docket. EPA has established an official public docket for this
action under docket identification (ID) number OPP-2003-0373. The
official public docket consists of the documents specifically
referenced in this action, any public comments received, and other
information related to this action. Although a part of the official
docket, the public docket does not include Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. The official public docket is the collection of materials
that is available for public viewing at the Public Information and
Records Integrity Branch (PIRIB), Rm. 119, Crystal Mall 2,
1921 Jefferson Davis Hwy., Arlington, VA. This docket facility is open
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal
holidays. The docket telephone number is (703) 305-5805.
2. Electronic access. You may access this Federal Register document
electronically through the EPA Internet under the ``Federal Register''
listings at http://www.epa.gov/fedrgstr/ A frequently updated electronic version of 40 CFR part 180 is available at http://.
http://www.access.gpo.gov/nara/cfr/cfrhtml_00/Title_40/ 40cfr1 80--00.html/,
a beta site currently under development. To access the OPPTS Harmonized
Guidelines referenced in this document, go directly to the guidelines
at http://www.epa.gov/opptsfrs/home/guidelin.htm/.
An electronic version of the public docket is available through
EPA's electronic public docket and comment system, EPA Dockets. You may
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public
comments, access the index listing of the contents of the official
public docket, and to access those documents in the public docket that
are available electronically. Although not all docket materials may be
available electronically, you may still access any of the publicly
available docket materials through the docket facility identified in
Unit I.B.1. Once in the system, select ``search,'' then key in the
appropriate docket ID number.
II. Background
In the Federal Register of February 15, 2002 (67 FR 7156) (FRL-
6822-2), EPA issued a notice pursuant to section 408 of FFDCA, 21
U.S.C. 346a, as amended by FQPA (Public Law 104-170), announcing the
filing of a pesticide petition (PP 1F6312) by Dow AgroScience LLC, 9330
Zionsville Road, Indianapolis, IN 46268. That notice included a summary
of the petition prepared by DowAgroScience, the registrant. The
petition requested that 40 CFR part 180 be amended by establishing
tolerances for residues of the insecticide sulfuryl fluoride and the
metabolite fluoride, from sulfuryl fluoride postharvest use, in or on:
1. Fluoride in or on the following raw agricultural commodities:
Date at 5 parts per million (ppm), fig at 5 ppm, plum, prune, dried at
5 ppm, grape, raisin at 5 ppm, fruit, dried at 5 ppm, almond at 10 ppm,
pecan at 23 ppm, pistachio at 18 ppm, walnut at 30 ppm, beechnut;
butternut; cashew; chestnut; chinquapin; filbert; nut, brazil; nut,
hickory; and nut, macadamia at 30 ppm, barley, grain at 10 ppm, corn,
field, grain; and corn, pop, grain at 7 ppm, oat, grain at 17 ppm,
rice, grain at 10 ppm, wheat, grain at 25 ppm, millet, grain; rice,
wild, grain; sorghum, grain; and triticale, grain at 25 ppm and on the
processed products corn, field, flour at 26 ppm, corn, field, grits at
10 ppm, corn, field, meal at 28 ppm, corn, field, oil at 3 ppm, rice,
brown at 14 ppm, rice, polished rice at 18 ppm, rice, bran at 31 ppm,
rice, hulls at 35 ppm, wheat, bran at 40 ppm, wheat, flour at 10 ppm,
wheat, germ at 98 ppm, wheat milled by products at 35 ppm, wheat,
shorts at 38 ppm, corn, field, refined oil at 3 ppm.
2. Sulfuryl fluoride in or on the following raw agricultural
commodities: Date at 0.03 ppm, fig at 0.05 ppm, plum, prune, dried at
0.01 ppm, grape, raisin at 0.01 ppm, fruit, dried at 0.05 ppm, almond
at 0.2 ppm, pecan at 6.0 ppm, pistachio at 0.5 ppm, walnut at 6.0 ppm,
beechnut; butternut; cashew; chestnut; chinquapin; filbert; nut,
brazil; nut, hickory; and nut, macadamia at 6.0 ppm, barley, grain at
0.01 ppm, corn, field, grain and corn, pop, grain at 0.04 ppm, oat,
grain at 0.01 ppm, rice, grain at 0.04 ppm, wheat, grain at 0.05 ppm,
millet, grain; rice, wild, grain; sorghum, grain; triticale, grain at
0.05 ppm and on the processed products corn, field, flour at 0.01 ppm,
corn, field, grits at 0.01 ppm, corn, field, meal at 0.01 ppm, corn,
field, refined oil at 9.0 ppm, rice, brown at 0.01 ppm, rice, polished
rice at 0.01 ppm, rice, bran at 0.01 ppm, rice, hulls at 0.08 ppm,
wheat, bran at 0.01 ppm, wheat, flour at 0.03 ppm, wheat, germ at 0.01
ppm, wheat milled byproducts at 0.01 ppm, wheat, shorts at 0.01 ppm.
The Agency has previously established temporary tolerances for
sulfuryl fluoride and fluoride on stored walnuts and raisins in
connection an Experimental Use Permit (EUP) for post-harvest sulfuryl
fluoride use (See 67 FR 5735, February 7, 2000) (FRL-6834-4). Sulfuryl
fluoride has never been used on stored walnuts and raisins, however,
because the California Department of Pesticide Regulation has not
issued the necessary state authorization to allow the EUP to proceed.
Because Dow Agrosciences has now requested that its EUP for sulfuryl
fluoride use on walnuts and raisins be withdrawn and EPA, in today's
action, is establishing permanent tolerances for sulfuryl fluoride on
walnuts and raisins, these temporary tolerances are being revoked, also
as a part of today's action. The Agency received a Hearing Request
dated April 8, 2002 in response to the temporary tolerance final rule
from Fluoride Action Network. Because the tolerances that were objected
to have now been revoked, the objections are moot and are denied on
that ground. EPA fully considered, however, all of the Fluoride Action
Network's objections as a part of today's action and has responded to
each significant objection lodged by the Fluoride Action Network.
The Agency received 17 sets of written comments (including 5 sets
of late comments) on the notice of filing published on February 15,
2002 (67 FR 7156). In addition, the Agency had previously received
comments on prior Federal Register tolerance documents related to the
establishment of tolerances for sulfuryl fluoride and inorganic
fluoride, including two sets of comments on the notice of filing of a
pesticide petition to establish temporary tolerances for residues of
fluoride and sulfuryl fluoride in or on walnuts and sulfuryl fluoride
in or on raisins, and to establish an exemption from the requirement of
a tolerance for inorganic fluoride in or on raisins published on June
15, 2001 (66 FR 32618) (FRL-6788-2), and 89 sets of comments (including
10 late comments) on the proposed rule to establish temporary
tolerances for sulfuryl fluoride and inorganic fluoride residues
resulting from application of sulfuryl fluoride in or on walnuts and
raisins published on September 5, 2001 (66 FR 46415). In
[[Page 3242]]
addition, an objection and request for hearing was submitted in
response to the establishment of temporary tolerances for sulfuryl
fluoride and inorganic fluoride residues resulting from application of
sulfuryl fluoride in or on walnuts and raisins published on February 7,
2002 (67 FR 5735).
The Agency has prepared a detailed response to the public comments
regarding the establishment of tolerances for sulfuryl fluoride and
inorganic fluoride on food including all public comments made to the
documents noted above resulting from the application of sulfuryl
fluoride as a post-harvest fumigant. This document has been made part
of the public docket OPP-2003-0373 for this regulatory action, and is
also available for review on the Internet (http://www.epa.gov/fedrgstr/)
.
In general, the comments addressed either procedural issues
concerning the process of establishing tolerance levels for sulfuryl
fluoride and total fluoride or substantive issues concerning the human
health and other consequences that would result from the use of
sulfuryl fluoride and increased human exposure to fluorides. Most of
the comments relate to fluoride exposure, fluoride toxicology and
issues related to the exposure to fluorides from fluoridated drinking
water. The longest and most significant of these comments came from the
Fluoride Action Network (FAN), which, among its comments, questioned
the safety of the current Maximum Contaminant Level Goal (MCLG) and
Secondary Maximum Contamination Level (SGML) for fluoride in drinking
water established by the Agency's Office of Water, under the Safe
Drinking Water Act. The Safe Drinking Water Act (SDWA) requires EPA to
review each National Primary Drinking Water Regulation (NPDWR) at least
once every 6 years and revise them, if appropriate. As part of this
review process, the Office of Water, has requested the National Academy
of Science (NAS) to review the current drinking water standards for
fluoride. The project scope from the NAS website states:
A subcommittee of the National Research Council's (NRC)
Committee on Toxicology (COT) will review toxicologic,
epidemiologic, and clinical data, particularly data published since
1993, and exposure data on orally ingested fluoride from drinking
water and other sources (e.g., food, toothpaste, dental rinses).
Based on those reviews the subcommittee will evaluate independently
the scientific basis of the EPA's maximum contaminant level goal
(MCLG) of 4 milligram per liter (mg/L) and secondary maximum
contaminant level (SMCL) of 2 mg/L in drinking water. The
subcommittee will advise EPA on the adequacy of its fluoride MCLG
and SMCL to protect children and others from adverse effects. The
subcommittee will consider the relative contribution of various
fluoride sources (e.g., food, dental-hygiene products) to total
exposure. The subcommittee will also identify data gaps and make
recommendations for future research relevant to setting the MCLG and
SMCL for fluoride. The subcommittee will not address questions of
economics, risk-benefit assessment, or water-treatment technology.
A previous NAS review of fluoride was published in 1993 (NRC 1993) and
served as the basis for the retention of the 4 mg/L MCLG and 2 mg/L
SMCL by EPA in 1993.
The comments cited a total of 120 scientific studies and other
published articles and books (see Unit VII.); these citations have all
been considered by the Agency and are discussed in further detail in
the assessment of the toxic effects resulting from exposure to fluoride
provided in Unit III. as well as within the detailed response to public
comments document. The analysis of the acceptability of fluoride
exposure is based on the current MCLG and SMCL for fluoride in drinking
water. The NAS is currently reviewing the adequacy of the present
drinking water standards for fluoride in light of relevant scientific
data that has been published subsequent to the 1993 review (National
Research Council (1993). Health effects of ingested fluoride. National
Academy Press, Washington, DC.). In connection with the sulfuryl
fluoride tolerance petition, EPA has separately reviewed the cited
studies (Dellarco 2003; Baetcke et al. 2003) and concludes that the
cited scientific data that has been published since 1993 does not
support adopting a reference point for evaluating the adverse health
effects of fluoride than that underlying the MCLG.
III. Aggregate Risk Assessment and Determination of Safety
Section 408(b)(2)(A)(i) of FFDCA allows EPA to establish a
tolerance (the legal limit for a pesticide chemical residue in or on a
food) only if EPA determines that the tolerance is ``safe.'' Section
408(b)(2)(A)(ii) of FFDCA defines ``safe'' to mean that ``there is a
reasonable certainty that no harm will result from aggregate exposure
to the pesticide chemical residue, including all anticipated dietary
exposures and all other exposures for which there is reliable
information.'' This includes exposure through drinking water and in
residential settings, but does not include occupational exposure.
Section 408(b)(2)(C) of FFDCA requires EPA to give special
consideration to exposure of infants and children to the pesticide
chemical residue in establishing a tolerance and to ``ensure that there
is a reasonable certainty that no harm will result to infants and
children from aggregate exposure to the pesticide chemical residue. . .
.''
EPA performs a number of analyses to determine the risks from
aggregate exposure to pesticide residues. For further discussion of the
regulatory requirements of section 408 of FFDCA and a complete
description of the risk assessment process, see the final rule on
Bifenthrin Pesticide Tolerances (62 FR 62961, November 26, 1997) (FRL-
5754-7).
Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the
available scientific data and other relevant information in support of
this action. EPA has sufficient data to assess the hazards of and to
make a determination on aggregate exposure, consistent with section
408(b)(2) of FFDCA, for a tolerance for residues of sulfuryl fluoride
and fluoride on numerous commodities at the levels specified in the
tables below. EPA's assessment of exposures and risks associated with
establishing the tolerance follows.
A. Toxicological Profile
EPA has evaluated the available toxicity data and considered its
validity, completeness, and reliability as well as the relationship of
the results of the studies to human risk. EPA has also considered
available information concerning the variability of the sensitivities
of major identifiable subgroups of consumers, including infants and
children. The nature of the toxic effects caused by sulfuryl fluoride
are discussed in Table 1 of this unit as well as the no observed
adverse effect level (NOAEL) and the lowest observed adverse effect
level (LOAEL) from the toxicity studies reviewed.
[[Page 3243]]
Table 1.--Subchronic, Chronic, and Other Toxicity
------------------------------------------------------------------------
Study Type/Guideline No. Results
------------------------------------------------------------------------
2-Week inhalation study--rat NOAEL = 83/89 (Male/Female)
milligrams/kilogram/day (mg/kg/day)
LOAEL = 249/267 (M/F) mg/kg/day based
on slightly increased kidney
weights, minimal histopathology in
kidney. At 495/534 high mortality,
decreased body weights, severe
histopathology in the kidney, gross
and histopathology in many tissues/
organs (secondary to kidney
effects); severe inflammation of
respiratory tissues in one survivor.
No treatment-related neurotoxicity).
------------------------------------------------------------------------
2-Week inhalation study--dog NOAEL = 26/27 (M/F) mg/kg/day
LOAEL = 79/80 (M/F) mg/kg/day based
on M&F intermittant tremors and
tetany during exposure, minimal
inflammatory changes in upper
respiratory tract, decreased body
weight (F only).
Note: Increased serum fluoride at >=
26/27 mg/kg/day
------------------------------------------------------------------------
2-Week inhalation study--rabbit NOAEL = 30/30 (M/F) mg/kg/day
LOAEL = 90/90 (M/F) mg/kg/day based
on for both M&F malacia (necrosis)
in cerebrum, vacuolation of
cerebrum, moderate inflammation of
respiratory tissues
At 180/180 mg/kg/day for M&F
convulsions, hyperactivity, malacia
(necrosis) in cerebrum, vacuolation
of cerebrum, moderate inflammation
of respiratory tissues
------------------------------------------------------------------------
90-Day inhalation toxicity--rat NOAEL = 24/25 (M/F) mg/kg/day
(870.3100)....................... LOAEL = 80/83 (M/F) mg/kg/day based
on dental fluorosis*
At 240/250 (M/F) vacuolation of
caudate-putamen nucleus and white
fiber tracts of the internal capsule
of the brain, decreased body weight,
inflammation of nasal passages,
alveolar histiocytosis; slight
hyperplasia of renal collecting
ducts (F only)
------------------------------------------------------------------------
90-Day inhalation toxicity--mouse NOAEL = 38/36 (M/F) mg/kg/day
(870.3100)....................... LOAEL = 125/121 (M/F) mg/kg/day based
on for both M/F miscroscopic lesions
in caudate-putamen nucleus and
external capsule of the brain,
decreased body weight, decreased
body weight gain, follicular cell
hypertrophy in thyroid.
Note: Increased serum fluoride at >=
26/27 mg/kg/day
------------------------------------------------------------------------
90-Day inhalation toxicity--dog NOAEL = 25/26 (M/F) mg/kg/day
(870.3150)....................... LOAEL = 50/51 (M/F) mg/kg/day based
on slight histopathology of the
caudate nucleus of the basal
ganglia, decreased body weight,
decreased body weight gain,
transient neurological signs
(lateral recumbancy, tremors,
incoordination, salivation, tetany,
inactivity) starting at day 19 in
one M
------------------------------------------------------------------------
90-Day inhalation toxicity-- NOAEL = 8.6/8.5 (M/F) mg/kg/day
rabbit LOAEL = 29/28 (M/F) mg/kg/day based
(870.3150)....................... on for both M&F decreased body
weight, decreased liver weight,
dental fluorosis*, vacuolation of
white matter of the brain (F only).
At 86/85 mg/kg/day for both M&F
malacia (necrosis) and vacuolation
of putamen, globus pallidus and
internal and external capsules in
the brain, decreased body weight
gain, alveolar histiocytosis,
histopathology in nasal epithelium.
------------------------------------------------------------------------
Prenatal developmental--rat Maternal
(870.3700)....................... NOAEL = 225 ppm or 243 (F) mg/kg/day
LOAEL = >225 ppm or >243 (F) mg/kg/
day based on no observed effects.
Developmental
NOAEL = 225 or 243 (F) mg/kg/day
LOAEL = >225 ppm or 243 (F) mg/kg/day
based on no observed adverse
developmental effects
------------------------------------------------------------------------
Prenatal developmental--rabbit Maternal
(870.3700)....................... NOAEL = 75 ppm or 29 (F) mg/kg/day
LOAEL = 225 ppm or 86 mg/kg/day based
on decreased body weight and body
weight gain during treatment
Developmental
NOAEL = 75 ppm or 29/29 (M/F) mg/kg/
day
LOAEL = 225 ppm or 86 (F) mg/kg/day
based on decreased fetal body
weight, decreased crown-rump length,
possible increased fetal liver
pathology (pale liver)
------------------------------------------------------------------------
Reproduction and fertility Parental/Systemic
effects NOAEL = 5 ppm or 3.6/3.6 (M/F) mg/kg/
(870.3800)....................... day
LOAEL = 20 ppm or 14/14 (M/F) mg/kg/
day based on pale foci in lungs,
increased alveolar macrophages in
lungs
Reproductive
NOAEL = 14/14 (M/F) mg/kg/day
LOAEL = >150 ppm or 108/108 (M/F) mg/
kg/day based on no adverse effects
up to 150 ppm
Offspring
NOAEL = 20 ppm or 14 mg/kg/day
LOAEL = 150 ppm or 108 mg/kg/day
based on decreased pup weight in the
F1 and F2 generations (probably
secondary to maternal body weight
loss
------------------------------------------------------------------------
[[Page 3244]]
Chronic toxicity--rodents NOAEL = 3.5 for M and 16 for F mg/kg/
(870.4100)....................... day
LOAEL = 20 ppm or 14 for M and 80 ppm
or 62 for F mg/kg/day based on
dental fluorosis* in males and for
females greatly increased mortality
(due mostly to severe kidney
toxicity which led to kidney
failure); and histopathology in
brain (vacuolation in cerebrum and
thalmus/hypothalmus), adrenal
cortex, eyes, liver, nasal tissue
and respiratory tract; and, dental
fluorosis*.
No evidence of carcinogenicity in M
or F
------------------------------------------------------------------------
1-Year chronic inhalation NOAEL = 5.0/5.1 (M/F) mg/kg/day
toxicity--dog LOAEL = 20/20 (M/F) mg/kg/day based
(870.4100)....................... on for both M/F decreased body
weight gain, increased alveolar
macrophages in lungs, dental
fluorosis*. At 50/51 mg/kg/day for
both M/F increased mortality,
malacia (necrosis) in caudate
nucleus of brain, follicular cell
hypertrophy in thyroid,
histopathology in lung.
------------------------------------------------------------------------
18-Month carcinogenicity NOAEL = 25/25 (M/F) mg/kg/day
inhalation study--mouse LOAEL = 101/101 (M/F) mg/kg/day based
(870.4200)....................... on for both M/F cerebral vacuolation
in brain, decreased body weight
gain, follicular hypertrophy in
thyroid (M only), increased
mortality (F only), heart thrombus
(F only), and lung congestion (F
only)
No evidence of carcinogenicity in M
or F
------------------------------------------------------------------------
2-Year combined chronic/ NOAEL = 3.5 for M and 16 for F mg/kg/
carcinogenicity--rat day
(870.4300)....................... LOAEL = 20 ppm or 14 for M and 80 ppm
or 62 for F mg/kg/day based on
dental fluorosis* in males and for
females greatly increased mortality
(due mostly to severe kidney
toxicity which led to kidney
failure); and histopathology in
brain (vacuolation in cerebrum and
thalmus/hypothalmus), adrenal
cortex, eyes, liver, nasal tissue
and respiratory tract; and, dental
fluorosis*.
No evidence of carcinogenicity in M
or F
------------------------------------------------------------------------
Ames assay Negative without and with S-9
(870.5100)....................... activation
------------------------------------------------------------------------
Cytogenetics There was no significant increase in
(870.5395)....................... the frequency of micronucleated
polychromatic erythrocytes in bone
marrow at any sulfuryl fluoride
concentration or treatment time used
in the study (520 ppm).
------------------------------------------------------------------------
UDS Assay There was no evidence of unscheduled
(870.5550)....................... DNA synthesis over negative controls
up to 1,020 ppm of sulfuryl
fluoride.
------------------------------------------------------------------------
Acute inhalation neurotoxicity Systemic
study--rat (special design) NOAEL = 300 ppm or 354 (F) mg/kg/day
(870.6200)....................... LOAEL = >300 ppm or >354 (F) mg/kg/
day based on highest dose tested
Neurotoxic
NOAEL = 354 (F) mg/kg/day
LOAEL = >354 (F) mg/kg/day based on
highest dose tested
Note: study included
electrophysiological parameters, but
no microscopic pathology.
------------------------------------------------------------------------
90-Day inhalation neurotoxicity Systemic
study-rat (special design) NOAEL = 24/25 (M/F) mg/kg/day
(870.6200)....................... LOAEL = 80/83 (M/F) mg/kg/day based
on for both M and F pale foci in
pleura and macrophages in lungs,
dental fluorosis*
Neurotoxic
NOAEL = 24/25 (M/F) mg/kg/day
LOAEL = 80/83 (M/F) mg/kg/day based
on for both M and F disturbances in
electro-physiological parameters
(slowing of VER and SER waveforms in
F and ABR waveforms in M
------------------------------------------------------------------------
1-Year inhalation neurotoxicity NOAEL = 3.5/3.9 (M/F) mg/kg/day
study-rat (special design) LOAEL = 14/16 (M/F) mg/kg/day based
(870.6200)....................... on dental fluorosis*. At 52/62 mg/kg/
day (M/F) increased kidney and liver
weights, progressive kidney disease
and histopathology in lung.
Neurotoxic
NOAEL = 56/62 (M/F) mg/kg/day
LOAEL = 56/62 (M/F) mg/kg/day based
on highest dose tested
------------------------------------------------------------------------
Developmental neurotoxicity No study available. Study will be a
(870.6300)....................... condition of registration.
------------------------------------------------------------------------
Metabolism and pharmacokinetics Waived, Reregistration Eligibility
(870.7485)....................... Document, 1993
------------------------------------------------------------------------
Dermal penetration No study available. Not required for
(870.7600)....................... a gas.
------------------------------------------------------------------------
*As discussed later in this document, dental fluorosis is not considered
an adverse health effect, and the identification of that effect in any
of these toxicological studies has not served to define a safe level
of exposure to sulfuryl fluoride under the FFDCA.
[[Page 3245]]
Technical grade sulfuryl fluoride (99.8% active ingredient) is
marketed as a liquified gas in pressurized steel cylinders. The acute
oral LD50 of sulfuryl fluoride has been estimated to be
approximately 100 mg/kg in rats (Toxicity Category II). The acute
inhalation LC50 in mice (4-hour exposure) is 660 ppm (2.56
mg/L) in males and 642 ppm (2.49 mg/L) in females. The acute inhalation
LC50 in rats (1 hour exposure) is 4,512 ppm (17.5 mg/L).
Based on the use pattern for sulfuryl fluoride and several reported
incidences of human poisonings in the general toxicologic literature,
the Agency has classified sulfuryl fluoride as Toxicity Category I for
acute inhalation toxicity. When released from pressurized steel
cylinders, sulfuryl fluoride causes freezing of skin and eye tissues on
contact. Therefore, no dermal studies or eye irritation studies have
been required to be submitted. The acute dermal toxicity study (assumed
Toxicity Category IV), the primary skin irritation study (assumed
Toxicity Category IV), the primary eye irritation study (assumed
Toxicity Category I), and the dermal sensitization study (assumed to be
a non-sensitizer) have been waived. In a non-guideline study in which
rats were dermally exposed (with no inhalation exposure) to vapors of
sulfuryl fluoride gas at an exposure concentration of 9,600 ppm (40.3
mg/L) for 4 hours, no treatment-related adverse effects were observed.
In 2-week inhalation studies in rats, dogs and rabbits, different
target organs were affected. In rats, the primary target organ was the
kidneys, in which severe histopathological lesions were observed. These
lesions included papillary necrosis, hyperplasia of the epithelial
cells of the papillae, and degeneration/regeneration of collecting
tubules and proximal tubules. In dogs, the primary target organ was the
upper respiratory tract, in which minimal inflammation was observed.
Intermittant tremors and tetany were also noted in dogs. In rabbits,
the primary target organ was the brain, in which malacia (necrosis) and
vacuolation were observed in the cerebrum. Inflammation of the upper
respiratory tract was also noted in rabbits.
In subchronic (90-day) inhalation studies in rats, mice, dogs and
rabbits, the brain was the major target organ. Malacia and/or
vacuolation were observed in the white matter of the brain in all four
species. The portions of the brain most often affected were the
caudate-putamen nucleus in the basal ganglia, the white fiber tracts in
the internal and external capsules, and the globus pallidus of the
cerebrum. In dogs and rabbits, clinical signs of neurotoxicity
(including tremors, tetany, incoordination, convulsions and/or hind
limb paralysis) were also observed. Inflammation of the nasal passages
and histiocytosis of the lungs were observed in rats and rabbits; but
not in dogs, in which species inflammation of the upper respiratory
tract was more prominent in the 2-week study. In rats, kidney damage
was also observed. In mice, follicular cell hypertrophy was noted in
the thyroid gland. Decreased body weights and body weight gains were
also observed in rats, dogs and mice.
In chronic (1-2 year) inhalation studies in rats, dogs and mice,
target organs were the same as in the 90-day studies. In rats, severe
kidney damage caused renal failure and mortalities in many animals.
Additional gross and histopathological lesions in numerous organs and
tissues were considered to be secondary to the primary effect on the
kidneys. Other treatment-related effects in rats included effects in
the brain (vacuolation of the cerebrum and thalamus/ hypothalamus) and
respiratory tract (reactive hyperplasia and inflammation of the
respiratory epithelium of the nasal turbinates, lung congestion,
aggregates of alveolar macrophages). In dogs and mice, increased
mortalities, malacia and/or vacuolation in the white matter in the
brain, histopathology in the lungs, and follicular cell hypertrophy in
the thyroid gland were observed. Decreased body weights and body weight
gains were also noted in all three species. No evidence of
carcinogenicity was observed in either the combined chronic toxicity/
carcinogenicity study in rats or in the 18-month carcinogenicity study
in mice.
In specially designed acute and subchronic inhalation neurotoxicity
studies in rats, several electrophysiological parameters (EEGs) were
recorded in addition to observations for clinical signs of
neurotoxicity, functional observational battery (FOB) and motor
activity testing, and/or neurohistopathologic examination. Following
two exposures on consecutive days for 6 hours/day at 300 ppm of
sulfuryl fluoride (354 mg/kg/day), no treatment-related neurotoxic
effects were noted. In a 90-day study, changes in some EEG patterns
were observed at 100 ppm (80 mg/kg/day) and in several additional
patterns at 300 ppm (240 mg/kg/day). Vacuolation of the white matter in
the cerebrum was also observed at 300 ppm in this study. In a specially
designed 1-year chronic inhalation neurotoxicity study in rats, no
treatment-related neurotoxic effects were observed at 80 ppm (56 mg/kg/
day). EEGs were not recorded in this study.
In a developmental toxicity inhalation study in rats, no
developmental toxicity was observed in the pups. Although no maternal
toxicity was observed in this study at the highest dose tested (225
ppm), significant maternal toxicity (decreased body weight, body weight
gain and food consumption; increased water consumption and kidney
weights; and gross pathological changes in the kidneys and liver) was
observed in a previously conducted range-finding study at a slightly
higher dose level (300 ppm). In a developmental toxicity inhalation
study in rabbits, decreased fetal body weights were observed in the
pups. At the same dose level, decreased body weight and body weight
gain were observed in the dams. In a 2-generation reproduction
inhalation study in rats, vacuolation of the white matter in the brain,
pathology in the lungs (pale, gray foci; increased alveolar
macrophages) and decreased body weights were observed in the parental
animals. Decreased pup body weights in the F1 and F2 generations were
observed in the offspring. No effects on reproductive parameters were
noted in this study. No quantitative or qualitative evidence of
increased susceptibility of fetuses or pups was observed in the
developmental toxicity or reproduction studies on sulfuryl fluoride.
A battery of mutagenicity studies was negative for genotoxic
potential. The studies included a reverse gene mutation assay in
Salmonella typhimurium, an unscheduled DNA synthesis assay in primary
rat hepatocytes, and a micronucleus assay in mouse bone marrow cells.
In carcinogenicity studies in male and female rats and in male and
female mice, sulfuryl fluoride did not demonstrate evidence of
carcinogenic potential. Sulfuryl fluoride is classified as ``not likely
to be carcinogenic to humans'' according to the July 2, 1999 EPA Draft
Proposed Guidelines for Carcinogen Risk Assessment.
Poisonings and fatalities have been reported in humans following
inhalation exposure to sulfuryl fluoride. The severity of these effects
has depended on the concentration of sulfuryl fluoride and the duration
of exposure. Short-term inhalation exposure to high concentrations has
caused respiratory irritation, pulmonary edema, nausea, abdominal pain,
central nervous system depression, and numbness in the extremities. In
addition, there have been two reports of deaths of persons entering
houses treated with sulfuryl fluoride. One
[[Page 3246]]
person entered the house illegally and was found dead the next morning.
A second person died of cardiac arrest after sleeping in the house
overnight following fumigation. A plasma fluoride level of 0.5 mg/L (10
times normal) was found in this person following exposure. Prolonged
chronic inhalation exposures to concentrations of sulfuryl fluoride gas
significantly above the threshold limit value (TLV) of 5 ppm have
caused fluorosis in humans because sulfuryl fluoride is converted to
fluoride anion in the body. Fluorosis is characterized by binding of
fluoride anion to teeth (causing mottling of the teeth) and to bone.
Sulfuryl fluoride and fluoride anion are the residues of concern
associated with sulfuryl fluoride.
Fluoride anion. In assessing the risks associated with exposure to
fluoride, the Agency has relied on the toxicological assessment and
Maximum Contaminant Levels (MCLs) and Maximum Contaminant Level Goals
(MCLG) established by the Agency's Office of Water. The MCGL is the
maximum level of a contaminant in drinking water at which no known or
anticipated adverse effect on the health of persons would occur, and
which allows an adequate margin of safety. A MCL is an enforceable
level that is set as closely as feasible to the MCLG of a contaminant.
MCLGs are non-enforceable health goals. For fluoride, both the MCL and
the MCLG have been set at 4.0 ppm in order to protect against crippling
skeletal fluorosis. The Office of Water has also established a
secondary MCL (SMCL) for fluoride at 2.0 ppm. The SMCL is a non-
enforceable level established to be protective against the cosmetic and
aesthetic effects of objectionable dental fluorosis.
B. Toxicological Endpoints
The dose at which no adverse effects are observed (the NOAEL) from
the toxicology study identified as appropriate for use in risk
assessment is used to estimate the toxicological level of concern
(LOC). However, the lowest dose at which adverse effects of concern are
identified (the LOAEL) is sometimes used for risk assessment if no
NOAEL was achieved in the toxicology study selected. An uncertainty
factor (UF) is applied to reflect uncertainties inherent in the
extrapolation from laboratory animal data to humans and in the
variations in sensitivity among members of the human population as well
as other unknowns. An UF of 100 is routinely used, 10X to account for
interspecies differences and 10X for intraspecies differences.
Three other types of safety or uncertainty factors may be used:
``Traditional uncertainty factors''; the ``special FQPA safety
factor''; and the ``default FQPA safety factor.'' By the term
``traditional uncertainty factor,'' EPA is referring to those
additional uncertainty factors used prior to FQPA passage to account
for data base deficiencies. These traditional uncertainty factors have
been incorporated by the FQPA into the additional safety factor for the
protection of infants and children. The term ``special FQPA safety
factor'' refers to those safety factors that are deemed necessary for
the protection of infants and children primarily as a result of the
FQPA. The ``default FQPA safety factor'' is the additional 10X safety
factor that is mandated by the statute unless it is decided that there
are reliable data to choose a different additional factor (potentially
a traditional uncertainty factor or a special FQPA safety factor).
For dietary risk assessment (other than cancer) the Agency uses the
UF to calculate an acute or chronic reference dose (acute RfD or
chronic RfD) where the RfD is equal to the NOAEL divided by an UF of
100 to account for interspecies and intraspecies differences and any
traditional uncertainty factors deemed appropriate (RfD = NOAEL/UF).
Where a special FQPA safety factor or the default FQPA safety factor is
used, this additional factor is applied to the RfD by dividing the RfD
by such additional factor. The acute or chronic Population Adjusted
Dose (aPAD or cPAD) is a modification of the RfD to accommodate this
type of safety factor.
For non-dietary risk assessments (other than cancer) the UF is used
to determine the LOC. For example, when 100 is the appropriate UF (10X
to account for interspecies differences and 10X for intraspecies
differences) the LOC is 100. To estimate risk, a ratio of the NOAEL to
exposures (margin of exposure (MOE) = NOAEL/exposure) is calculated and
compared to the LOC.
The linear default risk methodology (Q*) is the primary method
currently used by the Agency to quantify carcinogenic risk. The Q*
approach assumes that any amount of exposure will lead to some degree
of cancer risk. A Q* is calculated and used to estimate risk which
represents a probability of occurrence of additional cancer cases
(e.g., risk). An example of how such a probability risk is expressed
would be to describe the risk as one in one hundred thousand (1 x
10-\5\), one in a million (1 x 10-\6\), or one in
ten million (1 x 10-\7\). Under certain specific
circumstances, MOE calculations will be used for the carcinogenic risk
assessment. In this non-linear approach, a ``point of departure'' is
identified below which carcinogenic effects are not expected. The point
of departure is typically a NOAEL based on an endpoint related to
cancer effects though it may be a different value derived from the dose
response curve. To estimate risk, a ratio of the point of departure to
exposure (MOEcancer = point of departure/exposures) is
calculated.
A summary of the toxicological endpoints for sulfuryl fluoride used
for human risk assessment is shown in Table 2 of this unit:
Table 2.--Summary of Toxicological Dose and Endpoints for sulfuryl fluoride for Use in Human Risk Assessment
----------------------------------------------------------------------------------------------------------------
Dose Used in Risk
Assessment, Special FQPA SF and
Exposure Scenario Interspecies and Level of Concern for Study and Toxicological
Intraspecies and any Risk Assessment Effects
Traditional UF
----------------------------------------------------------------------------------------------------------------
Acute dietary None, UF = N/A Not applicable No toxicological
endpoint attributable
to a single exposure
was identified in the
available toxicology
studies on sulfuryl
fluoride
----------------------------------------------------------------------------------------------------------------
Chronic dietary (all populations) NOAEL = 8.5 mg/kg/day Special FQPA SF = 1X 90-Day inhalation--
UF = 3,000............. cPAD = chronic RfD/ rabbit
Chronic RfD = 0.003 mg/ Special FQPA SF = LOAEL = 28 mg/kg/day
kg/day. 0.003 mg/kg/day. based on vacuolation
of white matter in the
brain of females.
----------------------------------------------------------------------------------------------------------------
[[Page 3247]]
Incidental oral (all durations) None Not applicable Due to sulfuryl
fluoride being a gas
and pattern of use, no
significant incidental
oral exposure is
anticipated.
----------------------------------------------------------------------------------------------------------------
Dermal (all durations) None Not applicable Due to sulfuryl
fluoride being a gas
and pattern of use, no
significant incidental
dermal exposure is
anticipated. No hazard
identified, therefore,
no quantification is
required.
----------------------------------------------------------------------------------------------------------------
Short-term inhalation (1 to 30 days) Inhalation study Residential LOC for MOE 2-Week inhalation--
NOAEL = 30 mg/kg/day = 1,000 Occupational rabbit
(100 ppm; 0.42 mg/L). LOC = 100 LOAEL = 90 mg/kg/day
(300 ppm; 1.25 mg/L)
based on malacia
(necrosis) and
vacuolation in brain,
inflammation of nasal
tissue and trachea
----------------------------------------------------------------------------------------------------------------
Intermediate-term inhalation (1 to 6 Inhalation study Residential LOC for MOE 90-Day inhalation-
months) NOAEL = 8.5 mg/kg/day = 1,000 rabbit
(100 ppm; 0.42mg/L). Occupational LOC for LOAEL = 28 mg/kg/day
MOE = 100. (100 ppm; 0.42 mg/L)
based on vacuolation
of white matter in the
brain of females.
----------------------------------------------------------------------------------------------------------------
Long-term inhalation (>6 months) Inhalation study Residential LOC for MOE 90-Day inhalation--
NOAEL = 8.5 mg/kg/day = 3,000 rabbit
(30 ppm; 0.13 mg/L). Occupational LOC for LOAEL = 28 mg/kg/day
MOE = 300. based on vacuolation
of white matter in the
brain of females
----------------------------------------------------------------------------------------------------------------
Cancer (oral, dermal, inhalation) Classified as not likely to be carcinogenic to humans
----------------------------------------------------------------------------------------------------------------
For sulfuryl fluoride, the end-point from an inhalation study is
being used to calculate the chronic RfD which is used to perform risk
assessments for oral exposure. In addition to being the only practical
way to administer a gas test material, the Agency believes this is a
very conservative methodology which is supported by the following
considerations:
The absorption of test material from inhalation exposure is
generally presumed to be 100%, where as absorption via oral exposure is
often times determined to be less than 100%.
A higher and more persistent level of parent test material in the
body may occur following inhalation exposure as compared to an oral
exposure because the parent test material is immediately distributed
throughout the circulatory system following inhalation, rather than the
first being directly shunted to the liver (where most metabolism
occurs) as in the case of oral exposure.
In addition, for sulfuryl fluoride, the NOAEL on which the chronic
RfD was calculated is from a study in rabbits (which is the most
sensitive species for the neurotoxic effects) and the LOAEL in this
study was close to a threshold effect level (the effect was observed
only in the female rabbit).
Fluoride anion. In assessing the risks associated with exposure to
fluoride, the Agency relied on the toxicological assessment and MCLG
established by the Agency's Office of Water for fluoride of 4.0 ppm. At
this time, based on the information available to the Agency, EPA is not
concluding that dental fluorosis associated with fluoride exposure is
an adverse health effect under the FFDCA. The current arguments that
dental fluorosis is more than a cosmetic effect are not sufficiently
persuasive to warrant regulation as an adverse health effect under the
FFDCA. Accordingly, consistent with the action taken by the Office of
Water under the Safe Drinking Water Act, 50 FR 47142 (November 14,
1985) (WH-FRL-2913-8(b)), the Agency believes the appropriate endpoint
for regulation under the FFDCA is skeletal fluorosis.
While the tolerance safety determination under the FFDCA is a
health based standard, FIFRA requires the balancing of all costs,
taking into account the economic, social, and environmental effects as
well as health based risks, against the benefits associated with the
pesticide use. Therefore, the Agency will consider dental fluorosis in
determining whether sulfuryl fluoride meets the requisite standard
under FIFRA.
Using body weight and water consumption estimates, the MCLG,
expressed mg/kg/day, for the population groups addressed in the
fluoride risk assessments are as follows:
U.S. population . . . . . . . . . . . 0.114 mg/kg/day
Infants (< 1 year old). . . . . . . . . . 0.571 mg/kg/day
Children 1-2 years old. . . . . . 0.308 mg/kg/day
Children 3-5 years old. . . . . . . 0.182 mg/kg/day
Children 6-12 years old . . . . . 0.100 mg/kg/day
Youth 13-19 years old . . . . . . 0.133 mg/kg/day
Adults 20+ years old. . . . . . . . 0.114 mg/kg/day
Females 13-49 years old . . . . . 0.131 mg/kg/day
For fluoride risk assessments addressed in this document, the term
``% of MCLG (as mg/kg/day)'' is analogous to a reference dose (RfD).
Percent of MCLG (expressed as mg/kg/day) use in acute risk
assessments. None. The Agency has not identified any toxicological
endpoint attributable to a single exposure of fluoride that would be
applicable to females (13-50 years old) or to the general population
(including infants and children).
Percent of MCLG (expressed as mg/kg/day) use in non-acute risk
assessments. For all short-term, intermediate-term, and chronic
assessments, the Agency
[[Page 3248]]
has converted the MCLG of 4.0 ppm to a mg/kg/day basis using standard
water consumption estimates and body weight data from the NHANES III
survey (U.S. EPA, 2000). Body weight data from the NHANES survey were
matched as closely as possible to the population subgroups addressed by
the DEEM-FCID dietary exposure modelling software. Use of the NHANES
data, rather than the Agency default body weights, avoids setting dose
levels too high due to underestimated body weights. These doses in
Table 3 below were used for all risk assessment durations and pathways
(oral, dermal, and inhalation) in a manner analogous to an RfD. That
is, the Agency would have concerns about the level of estimated risk if
the exposure estimates exceed 100% of ``MCLG (as mg/kg/day)'' as
defined in this rule.
The Agency notes that the EPA's Integrated Risk Information System
(IRIS) lists an oral RfD of 1 ppm fluoride in water for dental
fluorosis (IRIS Database). That RfD is based on a NOEL of 1 ppm with an
LOEL of 2 ppm and no modifying or uncertainty factors since the effect
was noted in a sensitive population and the duration of exposure was
appropriate for the effect and the population. The IRIS value has not
been used in this action since dental fluorosis is a cosmetic effect,
not a human health effect.
Table 3.--Toxicological Doses Used in the Fluoride Risk Assessment*
----------------------------------------------------------------------------------------------------------------
Water Conc.
Protective Water Body of MCLG (as
Population Subgroup Toxicological Effect of Effect, Consumption, Weight, kg mg/kg/day)
ppm L/day
----------------------------------------------------------------------------------------------------------------
U.S. population (total) Skeletal fluorosis 4 2 70 0.114
----------------------------------------------------------------------------------------------------------------
All infants (<1 year) Skeletal fluorosis 4 1 7 0.571
----------------------------------------------------------------------------------------------------------------
Children (1-2 years) Skeletal fluorosis 4 1 13 0.308
----------------------------------------------------------------------------------------------------------------
Children (3-5 years) Skeletal fluorosis 4 1 22 0.182
----------------------------------------------------------------------------------------------------------------
Children (6-12 years) Skeletal fluorosis 4 1 40 0.1
----------------------------------------------------------------------------------------------------------------
Youth (13-19 years) Skeletal fluorosis 4 2 60 0.133
----------------------------------------------------------------------------------------------------------------
Adults (20+ years) Skeletal fluorosis 4 2 70 0.114
----------------------------------------------------------------------------------------------------------------
Females (13-49 years) Skeletal fluorosis 4 2 61 0.131
----------------------------------------------------------------------------------------------------------------
*Doses are used in a manner analogous to an RfD and are used for all exposure pathways
Carcinogenicity. In its assessment of the health effects of
fluoride, the National Research Council (NRC) concluded that the
available laboratory data are insufficient to demonstrate a
carcinogenic effect of fluoride in animals. The NRC also concluded that
the weight of the evidence from more than 50 epidemiological studies
does not support the hypothesis of an association between fluoride
exposure and increased cancer risk in humans. National Research
Council, 1993.
The Agency for Toxic Substances and Disease Registry (ATSDR) and
the World Health Organization have come to similar conclusions. Based
on the findings of those bodies and the Agency's own review, the Agency
believes fluoride poses a negligible cancer risk.
C. Exposure Assessment
1. Dietary exposure from food and feed uses. This is the first
food-use for sulfuryl fluoride. Temporary tolerances were established
(40 CFR 180.575) for the residues of sulfuryl fluoride, in or on a
walnuts and raisins. Tolerances already exist for fluoride residues in
food in 40 CFR 180.145 to support use of cryolite in on on various raw
agricultural commodities. This action involves adding a new section
(1)(a)(3) to 40 CFR 180.145, i.e., an entry adding postharvest use of
Profume on stored commodites. Risk assessments were conducted by EPA to
assess dietary exposures from sulfuryl fluoride and inorganic fluoride
in food as follows:
i. Acute exposure. Acute dietary risk assessments are performed for
a food-use pesticide, if a toxicological study has indicated the
possibility of an effect of concern occurring as a result of a 1-day or
single exposure.
No toxicological endpoint attributable to a single exposure was
identified in the available toxicology studies for either sulfuryl
fluoride and/or fluoride; therefore, no acute dietary exposure analysis
was conducted.
ii. Chronic exposure. In conducting the chronic dietary risk
assessment EPA used the Dietary Exposure Evaluation Model software with
the Food Commodity Intake Database (DEEM-FCID), which incorporates food
consumption data as reported by respondents in the U.S. Department of
Agriculture 1994-1996 and 1998 Nationwide Continuing Surveys of Food
Intake by Individuals (CSFII). The following assumptions were made for
the chronic exposure assessments: The chronic analysis for sulfuryl
fluoride used anticipated residues (average residue) from residue
trials reflecting the maximum proposed use rate, percent market share
estimates and a dilution factor for flour commodities to reflect the
pre-fumigation draw down practice in grain mills. This assessment
includes quantitative estimates of dietary exposure from background
levels of fluoride in food, fluoride in water, and fluoride from the
pesticidal food uses of cryolite and sulfuryl fluoride; non-dietary
exposure from the use of fluoridated toothpaste, and non-dietary
exposure from fluoride residues in air. For each of these pathways of
exposure, residue estimates are conservative to moderately conservative
in nature. Other potential sources of fluoride exposure have not been
included in this assessment in a quantitative manner, primarily due to
lack of demographic and/or exposure information. Non-quantified
pathways of exposure are not expected to significantly increase
exposure estimates for the various population subgroups at large.
The chronic analysis for sulfuryl fluoride used average residue
values from residue trials reflecting the maximum proposed use, percent
market share estimates, and a dilution factor for flour commodities to
reflect the pre-fumigation draw-down practice in grain processing
mills. Based on these
[[Page 3249]]
assumptions, the refined chronic dietary risk estimates for all
population subgroups are less than 1% of the chronic population-
adjusted dose (cPAD) of 0.003 mg/kg/day.
Table 4.--Chronic Dietary Exposure Assessment for Sulfuryl Fluoride
----------------------------------------------------------------------------------------------------------------
Estimated Exposure, mg/
Population Subgroup Chronic PAD, mg/kg/day kg/day Risk, % of cPAD
----------------------------------------------------------------------------------------------------------------
U.S. population (total) 0.003 0.000003 <1
----------------------------------------------------------------------------------------------------------------
All infants (<1 year) 0.003 0.000002 <1
----------------------------------------------------------------------------------------------------------------
Children (1-2 years) 0.003 0.000004 <1
----------------------------------------------------------------------------------------------------------------
Children (3-5 years) 0.003 0.000004 <1
----------------------------------------------------------------------------------------------------------------
Children (6-12 years) 0.003 0.000003 <1
----------------------------------------------------------------------------------------------------------------
Youth (13-19 years) 0.003 0.000001 <1
----------------------------------------------------------------------------------------------------------------
Adults (20-49 yrs) 0.003 0.000003 <1
----------------------------------------------------------------------------------------------------------------
Adults (50+ years) 0.003 0.000004 <1
----------------------------------------------------------------------------------------------------------------
Females (13-49 years) 0.003 0.000003 <1
----------------------------------------------------------------------------------------------------------------
In addition to assessing the exposure to sulfuryl fluoride in food,
EPA assessed fluoride exposure from residues in foods from the use of
sulfuryl fluoride and/or cryolite as well as background levels in
foods. Also addressed quantitatively are exposure from the use of
fluoridated toothpaste, inhalation of fluoride from the atmosphere, and
consumption of fluoride-containing water. Other known potential sources
of fluoride exposure were not addressed quantitatively due to lack of
data regarding residues and/or data regarding the demographics of
exposure. Details regarding the residue profiles of the various
fluoride sources are discussed below.
Background fluoride in foods. Monitoring studies indicate fluoride
is ubiquitous in the food supply (e.g., World Health Organization.
2002; Rao,G. S. 1984; Sherlock, JC. 1984). The primary sources for
residues used in this background food assessment were Taves, D.R.
(1983) for plant-based foods, bovine and porcine commodities, and eggs;
Fein, N.J. and Cerklewski F.L. (2001) for poultry; and residue trials
for tree nuts and dried fruits (MRID 45510304). Average residue values
were used when available. In cases were a range was listed, the maximum
value in the range was used. In the 1983 study by Taves, 93 food items
from a hospital in an area with fluoridated water were analyzed for
fluoride content. The use of the Taves data accounts for the increase
in fluoride residues that may occur when foods are processed/prepared
in fluoridated water. Note that the residue estimates for dried fruits
and tree nuts are at the LOQ for the residue trial method and are most
likely overestimates of fluoride, based on the residue levels in other
commodities. Overall, these should be considered to be conservative to
slightly refined estimates of fluoride residues.
Cryolite. In evaluating the exposure to fluoride from the
agricultural uses of cryolite, residue trial data were matched as
closely as possible to the current maximum use patterns for this active
ingredient. Empirically derived processing factors were used for
processed commodities of grapes, citrus, mint, and tomato. Default
processing factors from DEEM Version 7.81 were used for all other
commodities. Overall, these should be considered to be moderately
refined estimates of residues.
EPA has concluded that dietary exposure to fluoride will utilize
30% of the MCLG (expressed as mg/kg/day) for the U.S. population, 18%
of the MCLG (expressed as mg/kg/day) for youth 13-19 years, 29% of the
MCLG (expressed as mg/kg/day) for children 3-5 years, and 27% of the
MCLG (expressed as mg/kg/day) for All infants less than 1 year. These
risk estimates are below the Agency's level of concern.
Table 5.--Total Chronic Exposure and Risk Estimates for Fluoride from Dietary Sources
----------------------------------------------------------------------------------------------------------------
Dietary Fluoride Anion Exposure Estimates, mg/kg/day Risk, %
Tox. ------------------------------------------------------- of MCLG
Population Subgroup Dose, mg/ Sulfuryl Total (as mg/kg/
kg/day Fluoride Cryolite Food Water Dietary day)
----------------------------------------------------------------------------------------------------------------
U.S. population (total) 0.114 0.0004 0.0006 0.0068 0.0269 0.0347 30
----------------------------------------------------------------------------------------------------------------
All infants (<1 year) 0.571 0.0005 0.0009 0.0093 0.1424 0.1531 27
----------------------------------------------------------------------------------------------------------------
Children (1-2 years) 0.308 0.0013 0.0031 0.0175 0.0407 0.0626 20
----------------------------------------------------------------------------------------------------------------
Children (3-5 years) 0.182 0.0012 0.0020 0.0149 0.0338 0.0519 29
----------------------------------------------------------------------------------------------------------------
Children (6-12 years) 0.100 0.0007 0.0008 0.0094 0.0227 0.0336 34
----------------------------------------------------------------------------------------------------------------
Youth (13-19 years) 0.133 0.0004 0.0003 0.0062 0.0176 0.0245 18
----------------------------------------------------------------------------------------------------------------
[[Page 3250]]
Adults (20-49 years) 0.114 0.0003 0.0004 0.0057 0.0252 0.0316 28
----------------------------------------------------------------------------------------------------------------
Adults (50+ yrs) 0.114 0.0003 0.0005 0.0050 0.0256 0.0314 28
----------------------------------------------------------------------------------------------------------------
Females (13-49 years) 0.131 0.0003 0.0005 0.0054 0.0238 0.0300 23
----------------------------------------------------------------------------------------------------------------
iii. Anticipated residue and percent crop treated (PCT)
information. Section 408(b)(2)(E) of FFDCA authorizes EPA to use
available data and information on the anticipated residue levels of
pesticide residues in food and the actual levels of pesticide chemicals
that have been measured in food. If EPA relies on such information, EPA
must require that data be provided 5 years after the tolerance is
established, modified, or left in effect, demonstrating that the levels
in food are not above the levels anticipated. Following the initial
data submission, EPA is authorized to require similar data on a time
frame it deems appropriate. As required by section 408(b)(2)(E) of
FFDCA, EPA will issue a data call-in for information relating to
anticipated residues to be submitted no later than 5 years from the
date of issuance of this tolerance.
Section 408(b)(2)(F) of FFDCA states that the Agency may use data
on the actual percent of food treated for assessing chronic dietary
risk only if the Agency can make the following findings: Condition 1,
that the data used are reliable and provide a valid basis to show what
percentage of the food derived from such crop is likely to contain such
pesticide residue; Condition 2, that the exposure estimate does not
underestimate exposure for any significant subpopulation group; and
Condition 3, if data are available on pesticide use and food
consumption in a particular area, the exposure estimate does not
understate exposure for the population in such area.
In addition, the Agency must provide for periodic evaluation of any
estimates used. To provide for the periodic evaluation of the estimate
of PCT as required by section 408(b)(2)(F) of FFDCA, EPA may require
registrants to submit data on PCT.
The Agency used PCT information as follows:
A routine chronic dietary exposure analysis for the postharvest
fumigant Profume was based on 20% of the nut crop, 40% of dried fruit,
2% of the stored grain will be treated postharvest with Profume.
The Agency believes that the three conditions previously discussed
have been met. With respect to Condition 1, EPA finds that the PCT
information described in this document for Profume used on postharvest
use on stored commodities is reliable and has a valid basis. Profume is
a postharvest fumigant of stored commodities that will replace methyl
bromide uses for which the Agency has good information about the actual
amounts used. It is also possible that Profume could replace other
fumigant products for which there are also use data available, although
not as refined as for MeBr. This has been considered when making the
percent crop treated estimates which are considered to be conservative,
i.e., estimating the upper range of the stored commodity market that
will likely be treated with Profume.
Tree nuts. Methyl bromide is used on nearly all walnuts and about
3% of almonds. Dow estimated sulfuryl fluoride use will not exceed 10%
on almonds and 20% on other nuts. The Agency used a PCT of 20% for all
tree nuts.
Dried fruit. Methyl bromide is used on 64% of prunes and 28% of
raisins. Sulfuryl fluoride and phosphine are expected to share the
market as a replacement for methyl bromide used to treat dried fruit.
The Agency used a PCT of 40% for all dried fruits.
Stored grains. (1) At flour mills: Wheat flour mills are typically
fumigated 2 to 3 times per year, and there is enough stored grain to
support 2 days of production at a typical flour mill facility. Three
fumigations per year would mean 6 days of exposed production or 6/350 =
1.7% of the grain handled by the mill would be exposed to sulfuryl
fluoride, assuming that all flour mill fumigations were done with
sulfuryl fluoride. (2) Other stored grains. Phosphine is used to
fumigate stored grain, and 10% to 15% of stored grain is presently
fumigated. It is expected that sulfuryl fluoride will replace only 10%
of the phosphine usage because some phosphine products may be easier
for some users than sulfuryl fluoride (one formulation of phosphine
only requires that you drop pellets compared to the application and
monitoring equipment required for sulfuryl fluoride), phosphine is less
expensive than sulfuryl fluoride, and many grain fumigations do not
require the faster fumigation of sulfuryl fluoride. Sulfuryl fluoride
is likely to used for resistance management in many situations.
Overall, it is expected only 1% to 1.5% of other stored grains will be
treated with sulfuryl fluoride. The Agency used a PCT of 2% for all
stored grains.
As to Conditions 2 and 3, regional consumption information and
consumption information for significant subpopulations is taken into
account through EPA's computer-based model for evaluating the exposure
of significant subpopulations including several regional groups. Use of
this consumption information in EPA's risk assessment process ensures
that EPA's exposure estimate does not understate exposure for any
significant subpopulation group and allows the Agency to be reasonably
certain that no regional population is exposed to residue levels higher
than those estimated by the Agency. Other than the data available
through national food consumption surveys, EPA does not have available
information on the regional consumption of food to which Profume may be
applied in a particular area.
2. Dietary exposure from drinking water. The Agency has determined
that because of the use pattern and physicochemical characteristics of
sulfuryl fluoride, neither residues of sulfuryl fluoride nor of
inorganic fluoride are expected to reach surface water or ground water
due to the postharvest fumigation (an indoor use) of the commodities
listed in Unit II. Residues of inorganic fluoride may be in drinking
water due to intentional fluoridation.
Monitoring data based on 16 states from 1983 to 1998 that has been
extrapolated to the U.S. (U.S. EPA, 2003) indicate that approximately
99% of the U.S. population is supplied with water containing, on
average, less than 2 ppm fluoride anion. In the current risk
[[Page 3251]]
assessment, the Agency has assumed a residue level of 2 ppm for tap
water and 1 ppm for water sources other than tap water. The optimal
fluoridation level for water is approximately 1 ppm. This residue level
is reflected in the final product (e.g., soft drinks) when production
is in areas with fluoridated water. Because of the inclusion of all
non-tap water at 1 ppm, these should be considered to be slightly
refined overall estimates of fluoride residues. The use of 2 ppm
fluoride in tap water and 1 ppm in other water sources likely results
in an overestimation of exposure for the general population, especially
those on public water systems (93% of the U.S. population based on 2002
Census figures). However, it may underestimate the level of residues
present in drinking water for certain regional populations in the U.S.
who are supplied by well water that is naturally high in fluoride. In
monitoring data (1991-2002) from the National Water Quality Assessment
(NAWQA) Program (http://water.usgs.gov/nawqa/), the concentration of
fluoride in groundwater samples designated as being used for domestic
purposes exceeded 2 ppm in at least one sample from 13 of 49 study
units. Study units are major river basins and aquifers across the
nation and typically encompass approximately 4000 square miles.
Examination of data from each of those 13 study units indicates that
there is a fair degree of spatial variability in fluoride levels.
Similar finding regarding spatial difference in fluoride concentration
have been noted in local monitoring studies. For example, data from
Lakewood Township, Minnesota show a fluoride concentration of 0.4 ppm
in a well located at a similar depth and only a few hundred feet from a
well with a fluoride concentration of 14.0 ppm (Hastreiter, et al.,
1992). Similar variations in fluoride levels over small geographic
areas were noted. Data are not available describing fluoride levels for
a specific source over time, and it is unclear whether or not there is
temporal, as well as spatial, variability in well water fluoride
concentrations. If temporal variability is similar in magnitude to the
spatial variability, then the 2-ppm estimate for fluoride in tap water
is conservative for even those populations living in high-fluoride
areas. Overall, the conservative values used for both fluoride residues
in drinking water and drinking water consumption as well as
conservative assumptions on exposure to fluoride through food and other
non-dietary sources should not understate exposure to the general
population or any major identifiable population subgroup.
3. From non-dietary exposure. The term ``residential exposure'' is
used in this document to refer to non-occupational, non-dietary
exposure (i.e., for sulfuryl fluoride, termiticide use).
Sulfuryl fluoride is currently registered for use on the following
residential non-dietary sites: fumigation of residential sites for
termites. The risk assessment was conducted using the following
residential exposure assumptions: Sulfuryl fluoride is registered for
fumigation of domestic structures. Exposure could occur when residents
re-occupy a fumigated home; however, the label restricts reentry to the
residence until the measured levels of sulfuryl fluoride are very low.
The Agency has determined, based the available exposure data supporting
the Vikane registration and the Vikane label restriction on reentry
that there is negligible exposure to sulfuryl fluoride from home
fumigation (B. Daiss, May 15, 2001, DP Barcode 274960).
Fluoride exposure may occur from non-dietary sources, including
incidental ingestion of toothpaste and inhalation of airborne fluoride.
Other non-dietary exposures may occur; however, the Agency has included
only these two in its quantitative assessment due to lack of data
regarding residue levels and/or exposure demographics. In order to take
into account these other sources of non-dietary exposure, the Agency
has used conservative assumptions when estimating exposure from
toothpaste and air in an effort to ensure that exposures are not
underestimated. Exposure estimates for fluoride from toothpaste and air
for all of the population subgroups (i.e., in DEEM-FCID) are addressed.
Toothpaste. A number of studies available in the open literature
have been conducted to determine the exposure to fluoride from the
incidental ingestion of toothpaste (e.g., Levy et al., 1995; Naccache
et al., 1992, 1990; Simard et al., 1989; Bruun and Thylstrup, 1988;
Barnhart et al., 1974). Due to the different techniques used to assess
toothpaste ingestion and the different foci in those studies, the
estimates of fluoride exposure from toothpaste are quite varied. A few
common threads can be found, however: (1) incidental toothpaste
ingestion decreases with age as children gain better control of the
swallowing reflex; and, (2) ingestion of toothpaste can be a
significant contributor to overall fluoride exposure.
Despite the variability in the estimates of ingested toothpaste,
maximum exposures to fluoride observed in those studies appear to
converge to approximately 3 mg/day. In assessing fluoride from
toothpaste, HED has used this maximum estimate of 3 mg/day and
normalized to body weight using the NHANES dody weight data for the
various population subgroups. The exposure estimates range from 0.005
to 0.03 mg/kg/day and should be considered conservative in nature;
especially for older population subgroups since exposure estimates were
not adjusted for the age-related decrease in toothpaste ingestion.
Air. Estimates of fluoride residues in air are presented in a
number of review articles (e.g., World Health Organization, 2002; Burt,
1992). In the U.S., airborne fluoride concentrations are highest around
smelters and industrialized area. In such areas, the fluoride
concentration does not typically exceed 3 [mu]g/m\3\. The Agency has
used standard respiration rates derived from OPP/HED Science Advisory
Council for Exposure Policy No. 12 (2/22/2001) and body weights to
convert 3 [mu]g/m\3\ to a mg/kg/day basis. Exposure estimates range
from 0.0006 to 0.0026 mg/kg/day. As with toothpaste, the risk estimates
derived from these exposure estimates are below the Agency's level of
concern.
Table 6.--Estimated Fluoride Exposure from Non-Dietary Sources
--------------------------------------------------------------------------------------------------------------------------------------------------------
Estimated Exposure, mg/kg/day
Population Subgroup Body Weight, kg Standard Respiration, -------------------------------------------------
m\3\/day Toothpaste Air
--------------------------------------------------------------------------------------------------------------------------------------------------------
U.S. population (total) 70 13.3 0.0043 0.0006
--------------------------------------------------------------------------------------------------------------------------------------------------------
All infants (<1 year) 7 4.5 0.0429 0.0019
--------------------------------------------------------------------------------------------------------------------------------------------------------
Children (1-2 years) 13 8.7 0.0231 0.0020
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 3252]]
Children (3-5 years) 22 8.7 0.0136 0.0012
--------------------------------------------------------------------------------------------------------------------------------------------------------
Children (6-12 years) 40 8.7 0.0075 0.0007
--------------------------------------------------------------------------------------------------------------------------------------------------------
Youth (13-19 years) 60 13.3 0.0050 0.0007
--------------------------------------------------------------------------------------------------------------------------------------------------------
Adults (20-49 years) 70 13.3 0.0043 0.0006
--------------------------------------------------------------------------------------------------------------------------------------------------------
Adults (50+ years) 70 13.3 0.0043 0.0006
--------------------------------------------------------------------------------------------------------------------------------------------------------
Females (13-49 years) 61 11.3 0.0049 0.0006
--------------------------------------------------------------------------------------------------------------------------------------------------------
In response to the EUP for sulfuryl fluoride, the Agency received
comments regarding, among other things, sources of fluoride that were
not considered in the EUP assessment. Most of those sources have been
addressed quantitatively above; however, the use of fluoride
supplements and the potential for increased exposure following food
preparation in Teflon-treated cookware were specific issues that were
not addressed numerically. Fluoride supplements are prescribed only by
a health care professional. The community of health care professionals
is aware of the potential for fluorosis and the use of supplements is
only advocated when aggregate exposure is insufficient to provide
protection against dental caries. Because the amount of fluoride
prescribed is made in consideration of other fluoride sources, the use
of fluoride supplements would not result in overexposure to fluoride.
With respect to increased exposure to fluoride from the use of Teflon-
treated cookware, Full and Parkins (1975) report an approximately 3-
fold increase in the fluoride concentration of water boiled in a
Teflon-coated pan relative to that of stainless steel or Pyrex glass.
Due to their experimental design and the manner in which final fluoride
concentrations are expressed, it is not possible to discern whether or
not the increased fluoride concentration was due to leaching of
fluoride from the Teflon or differential evaporation noted for the
Teflon cookware versus other materials. Given the inert nature of
Teflon and the strength of the covalent C-F bonds in the
tetrafluoroethylene polymer, it is unlikely that fluoride would be
released in sufficient quantities to increase its concentration in the
water by 3 times. Based on the uncertainties associated with the
experimental data and the properties of Teflon, the Agency does not
believe that Teflon-treated cookware is a significant source of
fluoride exposure.
4. Cumulative effects from substances with a common mechanism of
toxicity. Section 408(b)(2)(D)(v) of FFDCA requires that, when
considering whether to establish, modify, or revoke a tolerance, the
Agency consider ``available information'' concerning the cumulative
effects of a particular pesticide's residues and ``other substances
that have a common mechanism of toxicity.''
EPA does not have, at this time, available data to determine
whether sulfuryl fluoride or fluoride has a common mechanism of
toxicity with other substances. Unlike other pesticides for which EPA
has followed a cumulative risk approach based on a common mechanism of
toxicity, EPA has not made a common mechanism of toxicity finding as to
sulfuryl fluoride or fluoride and any other substances. Sulfuryl
fluoride does produce the metabolite fluoride also produced by the
insecticide cryolite and this risk assessment has included exposure
from both exposure sources. For the purposes of this tolerance action,
therefore, EPA has not assumed that sulfuryl fluoride and/or fluoride
has a common mechanism of toxicity with other substances. For
information regarding EPA's efforts to determine which chemicals have a
common mechanism of toxicity and to evaluate the cumulative effects of
such chemicals, see the policy statements released by EPA's OPP
concerning common mechanism determinations and procedures for
cumulating effects from substances found to have a common mechanism on
EPA's web site at http://www.epa.gov/pesticides/cumulative/.
D. Safety Factor for Infants and Children
1. In general. Section 408 of FFDCA provides that EPA shall apply
an additional tenfold margin of safety for infants and children in the
case of threshold effects to account for prenatal and postnatal
toxicity and the completeness of the data base on toxicity and exposure
unless EPA determines based on reliable data that a different margin of
safety will be safe for infants and children. Margins of safety are
incorporated into EPA risk assessments either directly through use of a
MOE analysis or through using uncertainty (safety) factors in
calculating a dose level that poses no appreciable risk to humans. In
applying this provision, EPA either retains the default value of 10X
when reliable data do not support the choice of a different factor, or,
if reliable data are available, EPA uses a different additional safety
factor value based on the use of traditional uncertainty factors and/or
special FQPA safety factors, as appropriate.
2. Prenatal and postnatal sensitivity. In the sulfuryl fluoride
developmental toxicity study in rats, neither quantitative nor
qualitative evidence of increased susceptibility of fetuses to in utero
exposure to sulfuryl fluoride was observed. In the sulfuryl fluoride
developmental study in rabbits, neither quantitative nor qualitative
evidence of increased susceptability of fetuses to in utero exposure to
sulfuryl fluoride was observed. In the sulfuryl fluoride 2-generation
reproductive study in rats, neither quantitative nor qualitative
evidence of increased susceptability of fetuses to sulfuryl fluoride
was observed.
A very large body of information regarding the toxicology of
fluoride is available in the open literature. A complete review or re-
presentation of that information is beyond the scope of this
assessment. For a comprehensive review of the toxicology of fluoride,
the reader is referred to publications by the World Health Organization
(2002), the National Research Council (1993), the Medical Research
Council (1992), and
[[Page 3253]]
the Department of Health and Human Services (Draft Document 1993). In
conducting the assessment for fluoride, the Agency has used the
toxicological assessment and Maximum Contaminant Level Goals (MCLGs)
established by the Agency's Office of Water. The MCLG was established
in 1986 and is based on an LOAEL of 20 mg/day, a safety factor of 2.5,
and an adult drinking water intake of 2 L/day. The use of a safety
factor of 2.5 ensures public health criteria while still allowing
sufficient concentration of fluoride in water to realize its beneficial
effects in protecting against dental caries.
3. Conclusion. There is a complete toxicity data base for sulfuryl
fluoride with the exception of a developmental neurotoxicity (DNT)
study in rats. The exposure data are sufficiently complete or are
estimated based on data that reasonably accounts for potential
exposures. Based on the available evidence, the Agency is requiring an
inhalation developmental neurotoxicity (DNT) study in rats (Guideline
No. 870.6300) as a condition of registration in order to more clearly
and fully characterize the potential for neurotoxic effects in young
animals.
The Agency has determined that a 10X FQPA safety factor in the form
of a data base uncertainty factor (UFDB) is needed to account for the
lack of the DNT study since the available data provide no basis to
support reduction or removal of the default 10X factor. The following
points were considered in this determination:
[sbull] The current regulatory dose for chronic dietary risk
assessment is the NOAEL of 8.5 mg/kg/day (30 ppm; 0.13 mg/L) selected
from a 90-day inhalation toxicity study in rabbits. This dose is also
used for intermediate- and long-term inhalation exposure risk
assessments. The current dose for the short-term inhalation exposure
risk assessment is the NOAEL of 30 mg/kg/day (100 ppm; 0.42 mg/L) from
a 2-week inhalation toxicity study in rabbits.
[sbull] After considering the dose levels used in the neurotoxicity
studies and in the 2-generation reproduction study, it is assumed that
the DNT study with sulfuryl fluoride will be conducted at dose levels
similar to those used in the 2-generation reproduction study (0, 5, 20,
150 ppm; 0, 0.02, 0.08, 0.6 mg/L). It is considered possible that the
results of the DNT study could impact the endpoint selection for risk
assessments because the lowest dose that may be tested in the DNT (5
ppm or 0.02 mg/L), based on the Agency's dose analysis, could become an
effect level which would necessitate an additional factor resulting in
doses which would then be lower than the current doses used for chronic
dietary (8.5 mg/kg/day), intermediate and long-term inhalation (30 ppm
or 0.13 mg/L) and short term inhalation (100 ppm or 0.42 mg/L) risk
assessments. Given these circumstances, the Agency does not have
sufficient reliable data justifying selection of an additional safety
factor for the protection of infants and children lower than the
default value of 10X. Therefore, a UFDB of 10X will be applied to
repeated dose exposure scenarios (i.e. chronic RfD, and residential
short, intermediate and long term inhalation) to account for the lack
of the DNT study with sulfuryl fluoride.
The Agency has determined that there is no need for a special FQPA
safety factor (i.e., 1X) since there are no residual uncertainties for
pre- and/or post-natal toxicity based on the following:
[sbull] In the developmental toxicity study in rats, neither
quantitative nor qualitative evidence of increased susceptibility of
fetuses to in utero exposure to sulfuryl fluoride was observed.
[sbull] In the developmental toxicity study in rabbits, neither
quantitative nor qualitative evidence of increased susceptibility of
fetuses to in utero exposure to sulfuryl fluoride was observed.
[sbull] In the 2-generation reproduction toxicity study in rats,
neither quantitative nor qualitative evidence of increased
susceptibility of fetuses to sulfuryl fluoride was observed.
Fluoride. Given the wealth of reliable human data on fluoride, EPA
believes no additional safety factor for the protection of children is
necessary (1X). Relying on the extensive data bearing on skeletal
fluorosis, EPA's Office of Water reduced the traditional intraspecies
safety factor to 2.5X. This is reasonable, especially given that the
NAS has recommended that a safe dose for fluoride should be set using
no intraspecies safety factor or any other safety factor.
E. Aggregate Risks and Determination of Safety
1. Acute risk. No toxicological endpoint attributable to a single
exposure was identified in the available toxicology studies for either
sulfuryl fluoride and/or fluoride; therefore, no acute risk is expected
from exposure to these compounds.
2. Chronic risk. Using the exposure assumptions described in this
unit for chronic exposure, EPA has concluded that aggregate exposure to
sulfuryl fluoride food will utilize less than 1% of the cPAD for the
U.S. population, less than 1% of the cPAD for all population subgroups.
EPA has concluded that aggregate exposure to fluoride from food
will utilize 35% of the MCLG (as mg/kg/day) for the U.S. population,
23% of the MCLG (as mg/kg/day) for youth 13-19 years, 37% of the MCLG
(as mg/kg/day) for children 3-5 years, 35% of the MCLG (as mg/kg/day)
for all infants less than 1 year, and 28% of the MCLG (as mg/kg/day)
for children 1-2 years. These risk estimates are below the Agency's
level of concern.
Table 7.--Aggregate Exposure and Risk Estimates for Fluoride
--------------------------------------------------------------------------------------------------------------------------------------------------------
Estimated Fluoride Exposure by Source, mg/kg/day
MCL/SMCL, -------------------------------------------------------------------------------
Population Subgroup mg/kg/day Sulfuryl Background % of MCLG
Fluoride Cryolite Food Water Toothpaste Air Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
U.S. population (total) 0.114 0.0004 0.0006 0.0068 0.0269 0.0043 0.0006 0.0397 35
--------------------------------------------------------------------------------------------------------------------------------------------------------
All infants (<1 year) 0.571 0.0005 0.0009 0.0093 0.1424 0.0429 0.0019 0.1980 35
--------------------------------------------------------------------------------------------------------------------------------------------------------
Children (1-2 years) 0.308 0.0013 0.0031 0.0175 0.0407 0.0231 0.0020 0.0877 28
--------------------------------------------------------------------------------------------------------------------------------------------------------
Children (3-5 years) 0.182 0.0012 0.0020 0.0149 0.0338 0.0136 0.0012 0.0668 37
--------------------------------------------------------------------------------------------------------------------------------------------------------
Children (6-12 years) 0.1 0.0007 0.0008 0.0094 0.0227 0.0075 0.0007 0.0419 42
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 3254]]
Youth (13-19 years) 0.133 0.0004 0.0003 0.0062 0.0176 0.0050 0.0007 0.0302 23
--------------------------------------------------------------------------------------------------------------------------------------------------------
Adults (20-49 years) 0.114 0.0003 0.0004 0.0057 0.0252 0.0043 0.0006 0.0365 32
--------------------------------------------------------------------------------------------------------------------------------------------------------
Adults (50+ years) 0.114 0.0003 0.0005 0.0050 0.0256 0.0043 0.0006 0.0364 32
--------------------------------------------------------------------------------------------------------------------------------------------------------
Females (13-49 years) 0.131 0.0003 0.0005 0.0054 0.0238 0.0049 0.0006 0.0355 27
--------------------------------------------------------------------------------------------------------------------------------------------------------
3. Short-term risk. Short-term aggregate exposure takes into
account residential exposure plus chronic exposure to food and water
(considered to be a background exposure level).
The Agency determined there is no need to quantify the inhalation
risk resulting from a single residential or occupational inhalation
exposure to sulfuryl fluoride. No treatment-related neurotoxic or other
effects were observed in a specially designed acute neurotoxicity
inhalation study in which rats were exposed on two consecutive days for
6 hours/day to concentrations up to 300 ppm of sulfuryl fluoride
(equivalent to 1.25 mg/L). Further, no appropriate endpoints resulting
from a single inhalation exposure were identified in any of the
available toxicity studies on sulfuryl fluoride. Therefore, no hazard
attributable to a single inhalation exposure was identified and
quantification of risk for single inhalation exposures was determined
to be unnecessary. The Agency notes that poisonings and fatalities have
been reported in humans following inhalation exposure to sulfuryl
fluoride. The severity of these effects has depended on the
concentration of sulfuryl fluoride and the duration of exposure. Short-
term inhalation exposure to high concentrations has caused respiratory
irritation, pulmonary edema, nausea, abdominal pain, central nervous
system depression, and numbness in the extremities. In addition, there
have been two reports of deaths of persons entering houses treated with
sulfuryl fluoride. One person entered the house illegally and was found
dead the next morning. A second person died of cardiac arrest after
sleeping in the house overnight following fumigation. A plasma fluoride
level of 0.5 mg/L (10 times normal) was found in this person following
exposure. These acute poisonings in humans, however, occurred only
after label directions were grossly violated and persons were
subsequently exposed to extremely high concentrations of sulfuryl
fluoride. Therefore, based on the best available data and current
policies, potential risks do not exceed the Agency's level of concern
if label directions and precautions are followed.
Fluoride is not expected to pose a short-term risk.
4. Intermediate-term risk. Intermediate-term aggregate exposure
takes into account residential exposure plus chronic exposure to food
and water (considered to be a background exposure level). Intermediate-
term residential exposure is not expected to occur with the use of
sulfuryl fluoride. Furthermore, sulfuryl fluoride residues will not
occur in water due to its extreme volatility as a gas; and based on the
toxicology of fluoride and the behaviors associated with fluoride
exposure a chronic risk assessment is appropriate not an intermediate-
term risk assessment. Therefore, based on the best available data and
current policies, potential risks do not exceed the Agency's level of
concern.
Fluoride is not expected to pose an intermediate-term risk.
5. Aggregate cancer risk for U.S. population. Sulfuryl fluoride and
fluoride are not expected to pose a cancer risk.
6. Determination of safety. Based on these risk assessments, EPA
concludes that there is a reasonable certainty that no harm will result
to the general population, and to infants and children from aggregate
exposure to sulfuryl fluoride and inorganic fluoride residues.
IV. Other Considerations
A. Analytical Enforcement Methodology
Adequate enforcement methodology are available to enforce the
tolerance expressions. The methods may be requested from: Chief,
Analytical Chemistry Branch, Environmental Science Center, 701 Mapes
Rd., Ft. Meade, MD 20755-5350; telephone number: (410) 305-2905; e-mail
address: residuemethods@epa.gov.
B. International Residue Limits
There are no CODEX MRLs established. These are the first food
tolerances for sulfuryl fluoride in the United States.
C. Conditions
The conditions for registration are discussed in the Profume Notice
of Registration. The Agency does note that the current MCLG and SMCL
are under review by the National Academy of Science as requested by the
Office of Water. This review is expected to be completed in 2005.
Should there be a change in the MCLG and/or SMCL by the Office of Water
then the registration of Profume may require revision.
V. Conclusion
Therefore, tolerances are established for sulfuryl fluoride and
inorganic fluoride residues of sulfuryl fluoride, in or on various
commodities at the level specified in the tables below.
VI. Objections and Hearing Requests
Under section 408(g) of FFDCA, as amended by FQPA, any person may
file an objection to any aspect of this regulation and may also request
a hearing on those objections. The EPA procedural regulations which
govern the submission of objections and requests for hearings appear in
40 CFR part 178. Although the procedures in those regulations require
some modification to reflect the amendments made to FFDCA by FQPA, EPA
will continue to use those procedures, with appropriate adjustments,
until the necessary modifications can be made. The new section 408(g)
of FFDCA provides essentially the same process for persons to
``object'' to a regulation for an exemption from the requirement of a
tolerance issued by EPA under new section 408(d) of FFDCA, as was
provided in the old sections 408 and 409 of FFDCA. However, the period
for filing objections is now 60 days, rather than 30 days.
[[Page 3255]]
A. What Do I Need to Do to File an Objection or Request a Hearing?
You must file your objection or request a hearing on this
regulation in accordance with the instructions provided in this unit
and in 40 CFR part 178. To ensure proper receipt by EPA, you must
identify docket ID number OPP-2003-0373 in the subject line on the
first page of your submission. All requests must be in writing, and
must be mailed or delivered to the Hearing Clerk on or before March 23,
2004.
1. Filing the request. Your objection must specify the specific
provisions in the regulation that you object to, and the grounds for
the objections (40 CFR 178.25). If a hearing is requested, the
objections must include a statement of the factual issues(s) on which a
hearing is requested, the requestor's contentions on such issues, and a
summary of any evidence relied upon by the objector (40 CFR 178.27).
Information submitted in connection with an objection or hearing
request may be claimed confidential by marking any part or all of that
information as CBI. Information so marked will not be disclosed except
in accordance with procedures set forth in 40 CFR part 2. A copy of the
information that does not contain CBI must be submitted for inclusion
in the public record. Information not marked confidential may be
disclosed publicly by EPA without prior notice.
Mail your written request to: Office of the Hearing Clerk (1900C),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460-0001. You may also deliver your request to the
Office of the Hearing Clerk in Rm. 104, Crystal Mall 2, 1921
Jefferson Davis Hwy., Arlington, VA. The Office of the Hearing Clerk is
open from 8 a.m. to 4 p.m., Monday through Friday, excluding legal
holidays. The telephone number for the Office of the Hearing Clerk is
(703) 603-0061.
2. Tolerance fee payment. If you file an objection or request a
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must
mail the fee to: EPA Headquarters Accounting Operations Branch, Office
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please
identify the fee submission by labeling it ``Tolerance Petition Fees.''
EPA is authorized to waive any fee requirement ``when in the
judgement of the Administrator such a waiver or refund is equitable and
not contrary to the purpose of this subsection.'' For additional
information regarding the waiver of these fees, you may contact James
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov,
or by mailing a request for information to Mr. Tompkins at Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001.
If you would like to request a waiver of the tolerance objection
fees, you must mail your request for such a waiver to: James Hollins,
Information Resources and Services Division (7502C), Office of
Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania
Ave., NW., Washington, DC 20460-0001.
3. Copies for the Docket. In addition to filing an objection or
hearing request with the Hearing Clerk as described in Unit VI.A., you
should also send a copy of your request to the PIRIB for its inclusion
in the official record that is described in Unit I.B.1. Mail your
copies, identified by docket ID number OPP-2003-0373, to: Public
Information and Records Integrity Branch, Information Resources and
Services Division (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001. In person or by courier, bring a copy to the location of the
PIRIB described in Unit I.B.1. You may also send an electronic copy of
your request via e-mail to: opp-docket@epa.gov. Please use an ASCII
file format and avoid the use of special characters and any form of
encryption. Copies of electronic objections and hearing requests will
also be accepted on disks in WordPerfect 6.1/8.0 or ASCII file format.
Do not include any CBI in your electronic copy. You may also submit an
electronic copy of your request at many Federal Depository Libraries.
B. When Will the Agency Grant a Request for a Hearing?
A request for a hearing will be granted if the Administrator
determines that the material submitted shows the following: There is a
genuine and substantial issue of fact; there is a reasonable
possibility that available evidence identified by the requestor would,
if established resolve one or more of such issues in favor of the
requestor, taking into account uncontested claims or facts to the
contrary; and resolution of the factual issues(s) in the manner sought
by the requestor would be adequate to justify the action requested (40
CFR 178.32).
VII. Statutory and Executive Order Reviews
This final rule establishes a tolerance under section 408(d) of
FFDCA in response to a petition submitted to the Agency. The Office of
Management and Budget (OMB) has exempted these types of actions from
review under Executive Order 12866, entitled Regulatory Planning and
Review (58 FR 51735, October 4, 1993). Because this rule has been
exempted from review under Executive Order 12866 due to its lack of
significance, this rule is not subject to Executive Order 13211,
Actions Concerning Regulations That Significantly Affect Energy Supply,
Distribution, or Use (66 FR 28355, May 22, 2001). This final rule does
not contain any information collections subject to OMB approval under
the Paperwork Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose
any enforceable duty or contain any unfunded mandate as described under
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law
104-4). Nor does it require any special considerations under Executive
Order 12898, entitled Federal Actions to Address Environmental Justice
in Minority Populations and Low-Income Populations (59 FR 7629,
February 16, 1994); or OMB review or any Agency action under Executive
Order 13045, entitled Protection of Children from Environmental Health
Risks and Safety Risks (62 FR 19885, April 23, 1997). This action does
not involve any technical standards that would require Agency
consideration of voluntary consensus standards pursuant to section
12(d) of the National Technology Transfer and Advancement Act of 1995
(NTTAA), Public Law 104-113, section 12(d) (15 U.S.C. 272 note). Since
tolerances and exemptions that are established on the basis of a
petition under section 408(d) of FFDCA, such as the tolerance in this
final rule, do not require the issuance of a proposed rule, the
requirements of the Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et
seq.) do not apply. In addition, the Agency has determined that this
action will not have a substantial direct effect on States, on the
relationship between the national government and the States, or on the
distribution of power and responsibilities among the various levels of
government, as specified in Executive Order 13132, entitled Federalism
(64 FR 43255, August 10, 1999). Executive Order 13132 requires EPA to
develop an accountable process to ensure ``meaningful and timely input
by State and local officials in the development of regulatory policies
that have federalism implications.'' ``Policies that have federalism
implications'' is defined in the Executive Order to include regulations
that have
[[Page 3256]]
``substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.'' This
final rule directly regulates growers, food processors, food handlers
and food retailers, not States. This action does not alter the
relationships or distribution of power and responsibilities established
by Congress in the preemption provisions of section 408(n)(4) of FFDCA.
For these same reasons, the Agency has determined that this rule does
not have any ``tribal implications'' as described in Executive Order
13175, entitled Consultation and Coordination with Indian Tribal
Governments (65 FR 67249, November 6, 2000). Executive Order 13175,
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.'' ``Policies that have tribal
implications'' is defined in the Executive Order to include regulations
that have ``substantial direct effects on one or more Indian tribes, on
the relationship between the Federal Government and the Indian tribes,
or on the distribution of power and responsibilities between the
Federal Government and Indian tribes.'' This rule will not have
substantial direct effects on tribal governments, on the relationship
between the Federal Government and Indian tribes, or on the
distribution of power and responsibilities between the Federal
Government and Indian tribes, as specified in Executive Order 13175.
Thus, Executive Order 13175 does not apply to this rule.
VIII. Congressional Review Act
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of this final rule in the Federal Register. This final
rule is not a ``major rule'' as defined by 5 U.S.C. 804(2).
List of Subjects in 40 CFR Part 180
Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.
Dated: January 13, 2004.
James Jones,
Director, Office of Pesticide Programs.
0
Therefore, 40 CFR chapter I is amended as follows:
PART 180--AMENDED
0
1. The authority citation for part 180 continues to read as follows:
Authority: 21 U.S.C. 321(q), 346(a) and 371.
0
2. Section 180.145 is amended by revising paragraph (a)(3) to read as
follows:
Sec. 180.145 Flourine compounds; tolerances for residues.
(a) * * *
(3) Tolerances are established for residues of fluoride in or on
the following commodities from the postharvest fumigation with sulfuryl
fluoride for the control of insects:
------------------------------------------------------------------------
Parts per
Commodity million
------------------------------------------------------------------------
Barley, bran, postharvest.................................. 45.0
Barley, flour, postharvest................................. 45.0
Barley, grain, postharvest................................. 15.0
Barley, pearled, postharvest............................... 45.0
Corn, aspirated grain fractions, postharvest............... 55.0
Corn, field, flour, postharvest............................ 35.0
Corn, field, grain, postharvest............................ 10.0
Corn, field, grits, postharvest............................ 10.0
Corn, field, meal, postharvest............................. 30.0
Corn pop, grain, postharvest............................... 10.0
Fruit, dried , postharvest (other than raisin)............. 3.0
Grape, raisin, postharvest................................. 7.0
Millet, grain, postharvest................................. 40.0
Nut, tree, Group 14, postharvest........................... 10.0
Oat, flour, postharvest.................................... 75.0
Oat, grain, postharvest.................................... 25.0
Oat, rolled, postharvest................................... 75.0
Pistachio, postharvest..................................... 10.0
Rice, bran, postharvest.................................... 31.0
Rice, grain, postharvest................................... 12.0
Rice, hulls, postharvest................................... 35.0
Rice, polished, postharvest................................ 25.0
Rice, wild, grain, postharvest............................. 25.0
Sorghum, grain, postharvest................................ 40.0
Triticale, grain, postharvest.............................. 40.0
Wheat, bran, postharvest................................... 40.0
Wheat, flour, postharvest.................................. 125.0
Wheat, germ, postharvest................................... 130.0
Wheat, grain, postharvest.................................. 40.04
Wheat, milled byproducts, postharvest...................... 130.0
Wheat, shorts, postharvest................................. 40.0
------------------------------------------------------------------------
[[Page 3257]]
* * * * *
0
3. Section 180.575 is amended by revising paragraph (a) to read as
follows:
Sec. 180.575 Sulfuryl fluoride; tolerance for residues.
(a)(1) General. Tolerances are established for residues of sulfuryl
fluoride in or on the following commodities from the postharvest
fumigation with sulfuryl fluoride for the control of insects:
------------------------------------------------------------------------
Parts per
Commodity million
------------------------------------------------------------------------
Barley, bran, postharvest.................................. 0.05
Barley, flour, postharvest................................. 0.05
Barley, grain, postharvest................................. 0.1
Barley, pearled, postharvest............................... 0.05
Corn, aspirated grain fractions, postharvest............... 0.05
Corn, field, flour, postharvest............................ 0.01
Corn, field, grain, postharvest............................ 0.05
Corn, field, grits, postharvest............................ 15.0
Corn, field, meal, postharvest............................. 0.01
Corn pop, grain, postharvest............................... 0.05
Fruit, dried, postharvest.................................. 0.05
Millet, grain, postharvest................................. 0.1
Nut, tree, Group 14, postharvest........................... 3.0
Oat, flour, postharvest.................................... 0.05
Oat, grain, postharvest.................................... 0.1
Oat, rolled, postharvest................................... 0.1
Pistachio, postharvest..................................... 3.0
Rice, bran, postharvest.................................... 0.01
Rice, grain, postharvest................................... 0.04
Rice, hulls, postharvest................................... 0.1
Rice, polished, postharvest................................ 0.01
Rice, wild, grain, postharvest............................. 0.05
Sorghum, grain, postharvest................................ 0.1
Triticale, grain, postharvest.............................. 0.1
Wheat, bran, postharvest................................... 0.05
Wheat, flour, postharvest.................................. 0.05
Wheat, germ, postharvest................................... 0.02
Wheat, grain, postharvest.................................. 0.1
Wheat, milled byproducts, postharvest...................... 0.05
Wheat, shorts, postharvest................................. 0.05
------------------------------------------------------------------------
(2) To assure safe use of this pesticide commodities treated with
sulfuryl fluoride must be aerated for at least 24 hours prior to
entering commerce.
* * * * *
[FR Doc. 04-1540 Filed 1-22-04; 8:45 am]
BILLING CODE 6560-50-S