[Code of Federal Regulations]
[Title 40, Volume 30]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR799.2475]

[Page 251-254]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 799_IDENTIFICATION OF SPECIFIC CHEMICAL SUBSTANCE AND MIXTURE TESTING 
REQUIREMENTS--Table of Contents
 
                 Subpart B_Specific Chemical Test Rules
 
Sec. 799.2475  2-Mercapto benzo thia zole.

    (a) Identification of test substance. (1) 2-Mercaptobenzothiazole 
(MBT, CAS No. 149-30-4) shall be tested in accordance with this section.
    (2) MBT of at least 97.6 percent purity (plus or minus 1.5 percent) 
shall be used as the test substance.
    (b) Persons required to submit study plans, conduct tests, and 
submit data. All persons who manufacture (including byproduct 
manufacture, and import of MBT and MBT-containing articles) or process 
or intend to manufacture or process MBT, other than as an impurity, 
after October 21, 1988, to the end

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of the reimbursement period shall submit letters of intent to conduct 
testing, submit study plans, conduct tests, and submit data, or submit 
exemption applications as specified in this section, subpart A of this 
part, and parts 790 and 792 of this chapter for single-phase rulemaking.
    (c) Chemical fate--(1) Aerobic aquatic biodegradation--(i) Required 
testing. Aerobic aquatic biodegradation testing shall be conducted with 
MBT in accordance with Sec. 796.3100 of this chapter.
    (ii) Reporting requirements. (A) The aerobic aquatic biodegradation 
test shall be completed and the final report submitted to EPA within 12 
months of the effective date of the final rule.
    (B) An interim progress report shall be submitted to EPA 6 months 
after the effective date of the final rule.
    (2) Indirect photolysis-screening level test--(i) Required testing. 
Indirect photolysis testing shall be conducted with MBT in accordance 
with Sec. 795.70 of this chapter.
    (ii) Reporting requirements. (A) The indirect photolysis test shall 
be completed and the final report submitted to EPA within 12 months of 
the effective date of the final rule.
    (B) An interim progress report shall be submitted to EPA 6 months 
after the effective date of the final rule.
    (3) Chemical mobility--(i) Required testing. Chemical mobility 
testing shall be conducted with MBT in accordance with Sec. 796.2750 of 
this chapter.
    (ii) Reporting requirements. (A) The chemical mobility test shall be 
completed and the final report submitted to EPA within 12 months of the 
effective date of the final rule.
    (B) An interim progress report shall be submitted to EPA 6 months 
after the effective date of this final rule.
    (d) Environmental effects--(1) Fish chronic toxicity--(i) Required 
testing. (A) Chronic toxicity testing of MBT shall be conducted using 
rainbow trout (Salmo gairdneri.) according to Sec. 797.1600 of this 
chapter, except for paragraphs (c)(4)(iv)(A), (c)(4)(x)(E) and 
(c)(4)(x)(F), (c)(6)(iv)(A), (d)(2)(vii)(A)(2), and (d)(3)(iv) of Sec. 
797.1600.
    (B) For the purpose of this section, the following provisions also 
apply:
    (1) The first feeding for the fathead and sheepshead minnow fry 
shall begin shortly after transfer of the fry from the embryo cups to 
the test chambers. Silversides are fed the first day after hatch. Trout 
species initiate feeding at swim-up. The trout fry shall be fed trout 
starter mash or live newly-hatched brine shrimp nauplii (Artemia salina) 
three times a day ad libitum, with excess food siphoned off daily. The 
minnow fry shall be fed live newly-hatched brine shrimp nauplii (Artemia 
salina) at least three times a day.
    (2) All physical abnormalities (e.g., stunted bodies, scoliosis, 
etc.) shall be photographed and preserved.
    (3) At termination, all surviving fish shall be measured for growth. 
Total length measurements should be used except in cases where fin 
erosion occurs, then the use of standard length measurements shall be 
permitted. Standard length measurements should be made directly with a 
caliper, but may be measured photographically. Measurements shall be 
made to the nearest millimeter (0.1 mm is desirable). Weight 
measurements shall also be made for each fish alive at termination (wet, 
blotted dry, and to the nearest 0.01 g for the minnows and 0.1 g for the 
trout). If the fish exposed to the toxicant appear to be edematous 
compared to control fish, determination of dry, rather than wet, weight 
is recommended.
    (4)(i) Test substance measurement. Prior to addition of the test 
substance to the dilution water, it is recommended that the test 
substance stock solution be analyzed to verify the concentration. After 
addition of the test substance, the concentration of test substance 
shall be measured in the test substance delivery chamber prior to 
beginning, and during, the test. The concentration of test substance 
should also be measured at the beginning of the test in each test 
concentration (including both replicates) and control(s), and at least 
once a week thereafter. Equal aliquots of test solution may be removed 
from each replicate chamber and pooled for analysis. If a malfunction in 
the delivery system is discovered, water samples shall be taken from the 
affected test chambers immediately and analyzed.

[[Page 253]]

    (ii) pH. It is recommended that a pH of 7 be maintained in the test 
chambers.
    (iii) Reporting. An analysis of the stability of the stock solution 
for the duration of the test shall be reported.
    (5) [Reserved]
    (6) For brook and rainbow trout, a 16-hour light and 8-hour dark 
photoperiod shall be provided.
    (ii) Reporting requirements. (A) The fish chronic toxicity test 
shall be completed and the final report submitted to EPA within 12 
months of the effective date of the final rule.
    (B) An interim progress report shall be submitted to EPA 6 months 
after the effective date of the final rule.
    (2) Daphnid chronic toxicity--(i) Required testing. (A) Daphnid 
chronic toxicity testing shall be conducted with MBT using Daphnia magna 
according to Sec. 797.1330 of this chapter.
    (B) For the purposes of this section, the following provisions also 
apply:
    (1) Test substance measurement. Test substance concentration shall 
be measured in the test substance delivery chamber prior to beginning, 
and during, the test.
    (2) pH. It is recommended that a pH of 7 be maintained in the test 
chambers.
    (3) Reporting. An analysis of the stability of the stock solution 
for the duration of the test shall be reported and data comparing trout 
starter mash with A. salina for supporting trout growth should be 
submitted with the final report.
    (ii) Reporting requirements. (A) The daphnid chronic toxicity test 
shall be completed and the final report submitted to EPA within 12 
months of the effective date of the final rule.
    (B) An interim progress report shall be submitted to EPA 6 months 
after the effective date of the final rule.
    (e) Health effects--(1) Developmental toxicity testing--(i) Required 
testing. Developmental toxicity testing shall be conducted in two 
mammalian species with MBT in accordance with Sec. 798.4900 of this 
chapter, using the oral route of administration.
    (ii) Reporting requirements. (A) The developmental toxicity test 
shall be completed and the final report submitted to EPA within 12 
months of the effective date of the final rule.
    (B) An interim progress report shall be submitted to EPA 6 months 
after the effective date of the final rule.
    (2) Reproductive toxicity--(i) Required testing. Reproductive 
toxicity testing shall be conducted with MBT in accordance with Sec. 
798.4700 of this chapter, using the oral route of administration.
    (ii) Reporting requirements. (A) The reproductive test shall be 
completed and the final report submitted to EPA within 29 months of the 
effective date of the final rule.
    (B) Progress reports shall be submitted to EPA at 6-month intervals 
beginning 6 months after the effective date of the final rule until 
submission of the final report.
    (3) Neurotoxicity--(i) Required testing. (A)(1) An acute and 
subchronic functional observation battery shall be conducted with MBT in 
accordance with Sec. 798.6050 of this chapter except for the provisions 
in paragraphs (d)(5) and (6) of Sec. 798.6050.
    (2) For the purpose of this section, the following provisions also 
apply:
    (i) Duration and frequency of exposure. For acute study, animals 
shall be administered MBT over a period not to exceed 24 hours. For 
subchronic study, animals shall be dosed daily for at least 90 days.
    (ii) Route of exposure. Animals shall be exposed to MBT orally.
    (B)(1) An acute and subchronic motor activity test shall be 
conducted with MBT in accordance with Sec. 798.6200 of this chapter 
except for the provisions in paragraphs (d)(5) and (6) of Sec. 
798.6200.
    (2) For the purpose of this section the following provisions also 
apply:
    (i) Duration and frequency of exposure. For acute study, animals 
shall be administered over a period not to exceed 24 hours. For 
subchronic study, animals shall be dosed daily for at least 90 days.
    (ii) Route of exposure. Animals shall be exposed to MBT orally.
    (C)(1) A subchronic neuropathology test shall be conducted with MBT 
in accordance with Sec. 798.6400 of this chapter except for the 
provisions in paragraphs (d)(5) and (6) of Sec. 798.6400.
    (2) For the purpose of this section, the following provisions also 
apply:

[[Page 254]]

    (i) Duration and frequency of exposure. Animals shall be dosed daily 
for at least 90 days.
    (ii) Route of exposure. Animals shall be exposed to MBT orally.
    (ii) Reporting requirements. (A) The functional observation battery, 
motor activity, and neuropathology tests shall be completed and the 
final reports for each test submitted to EPA within 18 months of the 
effective date of the final rule.
    (B) A progress report shall be submitted to EPA for the functional 
observation battery, motor activity, and neuropathology tests, 
respectively, 6 months after the effective date of the final rule.
    (4) Mutagenic effects--Chromosomal aberrations--(i) Required 
testing. (A) A dominant lethal assay shall be conducted with MBT in 
accordance with Sec. 798.5450 of this chapter, using the oral route of 
administration.
    (B) A heritable translocation assay shall be conducted with MBT in 
accordance with the test guideline specified in Sec. 798.5460 of this 
chapter if MBT produces a positive result in the dominant lethal assay 
conducted pursuant to paragraph (e)(4)(i)(A) of this section and if, 
after a public program review, EPA issues a Federal Register notice or 
sends a certified letter to the test sponsor specifying that the testing 
shall be initiated.
    (ii) Reporting requirements. (A) Mutagenic effects--Chromosomal 
aberration testing of MBT shall be completed and the final report 
submitted to EPA as follows: Dominant lethal assay, within 12 months 
after the effective date of this rule; heritable translocation assay, 
within 24 months after notification under paragraph (e)(4)(i)(B) of this 
section that the testing shall be initiated.
    (B) For the dominant lethal assay, an interim progress report shall 
be submitted to EPA 6 months after the effective date of the final rule; 
for the heritable translocation assay, progress reports shall be 
submitted to EPA at 6-month intervals beginning 6 months after the date 
of EPA's notification of the test sponsor that testing shall be 
initiated until submission of the final report.
    (f) Effective date. (1) The effective date of this final rule is 
October 21, 1988, except for paragraphs (a)(2), (d)(1)(i), 
(d)(2)(i)(B)(3), and (e)(3)(ii)(A) of this section. The effective date 
for paragraphs (a)(2), (d)(1)(i), (d)(2)(i)(B)(3), and (e)(3)(ii)(A) of 
this section is March 1, 1990.
    (2) The guidelines and other test methods cited in this rule are 
referenced as they exist on the effective date of the final rule.

[53 FR 34530, Sept. 7, 1988; 53 FR 37393, Sept. 26, 1988, as amended at 
55 FR 7326, Mar. 1, 1990; 58 FR 34205, June 23, 1993]