[Federal Register: September 18, 2008 (Volume 73, Number 182)]
[Proposed Rules]
[Page 54083-54089]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18se08-19]
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DEPARTMENT OF AGRICULTURE
Animal and Plant Health Inspection Service
9 CFR Parts 94 and 95
[Docket No. APHIS-2008-0093]
Bovine Spongiform Encephalopathy; Minimal-Risk Regions and
Importation of Meat, Meat Byproducts, and Meat Food Products Derived
From Bovines 30 Months of Age or Older
AGENCY: Animal and Plant Health Inspection Service, USDA.
[[Page 54084]]
ACTION: Request for comments.
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SUMMARY: This document requests comment on the removal of the delay of
applicability of certain provisions of the rule entitled ``Bovine
Spongiform Encephalopathy; Minimal-Risk Regions and Importation of
Commodities,'' published in the Federal Register on January 4, 2005, 70
FR 460-553. The delay of applicability was removed in a final rule
entitled ``Bovine Spongiform Encephalopathy; Minimal-Risk Regions;
Importation of Live Bovines and Products Derived from Bovines,''
published in the Federal Register on September 18, 2007, 72 FR 53314-
53379.
DATES: We will consider all comments that we receive on or before
November 17, 2008.
ADDRESSES: You may submit comments by either of the following methods:
Federal eRulemaking Portal: Go to http://
www.regulations.gov/fdmspublic/component/
main?main=DocketDetail&d=APHIS-2008-0093 to submit or view comments and
to view supporting and related materials available electronically.
Postal Mail/Commercial Delivery: Please send two copies of
your comment to Docket No. APHIS-2008-0093, Regulatory Analysis and
Development, PPD, APHIS, Station 3A-03.8, 4700 River Road Unit 118,
Riverdale, MD 20737-1238. Please state that your comment refers to
Docket No. APHIS-2008-0093.
Reading Room: You may read any comments that we receive on this
docket, as well as APHIS supporting materials referenced in this
docket, in our reading room. The reading room is located in room 1141
of the USDA South Building, 14th Street and Independence Avenue, SW.,
Washington, DC. Normal reading room hours are 8 a.m. to 4:30 p.m.,
Monday through Friday, except holidays. To be sure someone is there to
help you, please call (202) 690-2817 before coming.
Other Information: Additional information about APHIS and its
programs is available on the Internet at http://www.aphis.usda.gov.
FOR FURTHER INFORMATION CONTACT: Dr. Lisa Ferguson, ASEP Director,
National Center for Animal Health Programs, VS, APHIS, 4700 River Road
Unit 46, Riverdale, MD 20737-1231; (301) 734-6188.
SUPPLEMENTARY INFORMATION:
Background
The Animal and Plant Health Inspection Service (APHIS) of the U.S.
Department of Agriculture (USDA or Department) regulates the
importation of animals and animal products into the United States to
guard against the introduction of animal diseases. The regulations in 9
CFR parts 93, 94, 95, and 96 (referred to below as the regulations)
govern the importation of certain animals, birds, poultry, meat, other
animal products and byproducts, hay, and straw into the United States
in order to prevent the introduction of various animal diseases,
including bovine spongiform encephalopathy (BSE), a chronic
degenerative disease affecting the central nervous system of cattle.
Nature of BSE
BSE belongs to the family of diseases known as transmissible
spongiform encephalopathies (TSEs). All TSEs affect the central nervous
system of infected animals. However, the distribution of infectivity in
the body of the animal and mode of transmission differ according to the
species and the TSE agent. In addition to BSE, TSEs include, among
other diseases, scrapie in sheep and goats, chronic wasting disease in
deer and elk, and Creutzfeldt-Jakob disease in humans.
The agent that causes BSE has yet to be fully characterized. The
theory that is most accepted in the international scientific community
is that the agent is an abnormal form of a normal protein known as
cellular prion protein. The BSE agent does not evoke a traditional
immune response or inflammatory reaction in host animals. BSE is
confirmed by post-mortem examination of an animal's brain tissue, which
may include detection of the abnormal form of the prion protein in the
brain tissues. The pathogenic form of the protein is both less soluble
and more resistant to degradation than the normal form. The BSE agent
is resistant to heat and to normal sterilization processes.
BSE is not a contagious disease, and therefore is not spread
through casual contact between animals. Scientists believe that the
primary route of transmission is through ingestion of feed that has
been contaminated with a sufficient amount of tissue from an infected
animal. This route of transmission can be prevented by excluding
potentially contaminated materials from ruminant feed.
Roles of Different Agencies
APHIS, an animal health agency within USDA, promulgates its
regulations regarding BSE under the authority of the Animal Health
Protection Act (7 U.S.C. 8301 et seq.), which gives the Secretary broad
discretion to regulate the importation of animals and animal products
if necessary to protect the health of U.S. livestock.
Because variant Creutzfeldt-Jakob Disease (vCJD) in humans has been
linked to exposure to the BSE agent, APHIS collaborates with other
Federal agencies with regulatory responsibility for assuring food
safety and the protection of human health to implement a comprehensive
coordinated U.S. response to BSE. Within USDA, protecting human health
from the risks of BSE is carried out by the Food Safety and Inspection
Service (FSIS), the agency charged with responsibility for
administering the Federal Meat Inspection Act, which was enacted to
ensure that meat and meat food products distributed in commerce are
wholesome, not adulterated, and properly marked, labeled, and packaged.
The USDA agencies carry out their programs in close coordination with
the following Centers of the Food and Drug Administration (FDA) of the
U.S. Department of Health and Human Services: The Center for Veterinary
Medicine regarding animal feed; the Center for Food Safety and Applied
Nutrition regarding foods other than meat, poultry, and egg products;
and other Centers regarding drugs, biologics, and devices containing
bovine material. These agencies collaborate, issuing regulations under
their respective authorities.
Tissue Localization
Some bovine tissues have demonstrated infectivity, whereas others
have not. Most of the information on the development and distribution
of tissue infectivity in BSE-infected cattle has been derived from
experimental pathogenesis studies conducted in the United Kingdom
(Wells, et al., 1994; 1996; 1998; 1999; 2005). In these studies, cattle
were deliberately infected with BSE through oral exposure to the brain
tissue of cattle with confirmed BSE. Subsets of the experimentally
infected cattle were killed at regular intervals as the disease
progressed. At each interval, the tissues of the infected cattle were
examined for histopathological changes consistent with BSE and for
abnormal prion proteins. Also, at each interval, a mouse assay was
done--i.e., tissues of the BSE infected cattle were injected
intracerebrally and intraperitoneally into mice to identify those
tissues of cattle containing infectivity.
The pathogenesis studies involved 30 animals, each of which
received a single dose of 100g of infected brain at 4 months of age
(Wells, et al., 1994; 1996;
[[Page 54085]]
1998; 1999; 2005). This dose is probably 10-100 times greater than that
associated with field exposure via feed (DEFRA 2005). The studies
demonstrate that in cattle infected with BSE, the total amount of
infectivity in the animal, as well as the distribution of infectivity
in the animal's body, change over time (Wells, et al., 1994; 1996;
1998; 1999; 2005). The highest levels of infectivity were detected in
the brain and spinal cord at the end stages of disease. Some cattle
exhibited clinical signs of BSE as early as 35 months after oral
exposure to the BSE agent. By 37 months after oral exposure, all five
animals that were still alive demonstrated clinical evidence of BSE.
Infectivity was found in cattle with clinical signs of BSE in the
brain, spinal cord, dorsal root ganglia (DRG),\1\ trigeminal ganglia,
and the distal ileum of the small intestine.
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\1\ DRG are clusters of nerve cells attached to the spinal cord
that are contained within the bones of the vertebral column. ``DRG''
as used in this document has the same meaning as the term ``dorsal
spinal nerve root ganglia.'' Trigeminal ganglia are clusters of
nerve cells connected to the brain that lie close to the exterior of
the skull.
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BSE infectivity was demonstrated in the brain, spinal cord, and DRG
as early as 32 months after oral exposure to the BSE agent in some
cattle (Wells, et al., 1994; 1996; 1998; 1999; 2005). Infectivity was
demonstrated in these tissues 3 months before animals began to develop
clinical signs of the disease. Infectivity was demonstrated in the
distal ileum of cattle 6 to 18 months after oral exposure to the BSE
agent and again at 38 months and 40 months after oral exposure. A
similar, more recent, study (Espinosa, et al., 2007) examined the
infectivity of tissues from these same animals by intracerebral
inoculation of highly sensitive transgenic mice overexpressing bovine
PrP. This study's findings were similar to those of Wells, et al.,
described above. In addition, infectivity in the sciatic nerve was
found at low levels only after 30 months from exposure. No detectable
infectivity was found in the spleen, skeletal muscle, blood or urine of
asymptomatic cattle.
As explained by the United Kingdom's Department for Environment,
Food and Rural Affairs (DEFRA) and by the European Commission's
Scientific Steering Committee, a second phase of the pathogenesis
studies, which used a cattle bioassay as an endpoint, was conducted to
ensure that low levels of infectivity that may not have been detected
in the first phase using the mouse bioassay were not missed (DEFRA
2006; EC SSC 2002). This second phase of the study was completed in
March 2007 (Gerald Wells, personal communication, 2008).
In the cattle bioassay, tissues from the same cattle orally exposed
to BSE in the earlier pathogenesis studies were injected directly into
the brain of BSE-free cattle (DEFRA 2005). This method is considered to
be several hundred-fold more sensitive in detecting BSE infectivity
than the mouse bioassay (DEFRA 2005). Preliminary results from the
cattle bioassay study demonstrate that, in addition to the materials
that were found to contain infectivity when the mouse bioassay was
used, the tonsils of calves 10 months after oral exposure to the BSE
agent also contain infectivity. However, because only one of five
animals injected with tonsil material from infected animals developed
clinical BSE at 45 months post-inoculation, the level of infectivity in
the tonsils appears to be very low.
BSE infectivity has not been demonstrated in the muscle tissue of
BSE-infected cattle examined in these studies through either the mouse
bioassay or the cattle assays (Wells 1996; 2005; personal communication
2008). All assays of the skeletal muscle pools were completed in March
2007 (Wells, personal communication 2008).
In addition to these studies on experimentally infected cattle,
distribution of tissue infectivity has also been studied in cattle
exposed to BSE under field conditions. In these animals, at the end
stages of the incubation period with demonstrated clinical signs, BSE
infectivity has been confirmed by mouse bioassay only in the brain,
spinal cord, and retina of the eye (EC SSC 2001).
In a recent study, mice, genetically engineered to be highly
susceptible to BSE and to overexpress the bovine prion protein, were
inoculated with tissues from an end-stage clinically affected BSE-
infected cow (Buschmann and Groschup, 2005). The sensitivity of these
mice to infection is significantly greater than other mice panels used
in bio-assays, and the sensitivity is even greater than that of cattle
by approximately tenfold. This study demonstrated low levels of
infectivity in the facial and sciatic nerves of the peripheral nervous
system when injected into these highly sensitive mice. While this
study, and the 2007 study by Espinosa, et al., produced interesting
findings that can help further characterize the pathogenesis of BSE,
they cannot be extrapolated into the context of the risk presented by
natural (i.e., field) exposure pathways. The findings may be influenced
by the overexpression of prion proteins in these genetically engineered
mice. Any apparent levels of infectivity are low in these extremely
sensitive mice and would be even lower in other species such as cattle.
Moreover, the route of administration to the mice was both
intraperitoneal and intracerebral, both of which are very efficient
routes of infection as compared to oral consumption.
Tissues that have demonstrated infectivity, and thus are likely to
contain the infectious BSE agent in infected cattle, are brain, tonsil,
spinal cord, eyes, trigeminal ganglia, DRG, and distal ileum.
Approximately 90 percent of the infectivity is associated with the
brain, spinal column, DRG, and trigeminal ganglia. The remaining 10
percent is associated with the infectivity in the distal ileum. In BSE,
as with other TSEs, the total amount of infectivity in an animal
increases throughout the incubation period, reaching the highest load
at the end of that period, very close to the death of the animal.
Infectivity is considered to increase exponentially, reaching 4.5 logs
less than a clinical case at 50 percent of the incubation period and 3
logs less than a clinical case by 70 percent of the incubation period
(Comer and Huntly, 2003).
All of this research has contributed to the definition of which
tissues should be deemed specified risk materials (SRMs). Both the
types of tissues, and the understanding of the progression of the
infectivity throughout the incubation period contribute to the
definition of SRMs. Affiliated tissues or structures such as skull or
vertebral column are also considered risk materials because of the
difficulty in separating out small tissues such as DRG from the
vertebral column. The risks associated with tissue localization can be
mitigated by excluding SRMs from the food or feed chain or by excluding
them completely from importation. FSIS and FDA regulations regarding
SRMs are based on this scientific knowledge and an understanding of the
mitigative effects of exclusion of SRMs (FSIS, 2004; 2004a; 2004b;
2005; 2007; FDA, 2004; 2005; 2007; 2008).
There are some studies available that report finding the presence
of the abnormal prion protein in various tissues (Buschmann and
Groschup, 2005; Masujin et al., 2007). As new methods are developed
that provide increased sensitivity to detect abnormal PrP, such
demonstrations of the presence of abnormal PrP in various tissues may
continue. However, demonstrating the presence of PrP\BSE\ does not
necessarily indicate the presence of BSE infectivity, especially if no
infectivity is demonstrated via the
[[Page 54086]]
most direct method available: cattle-to-cattle exposure via
intracerebral inoculation. Therefore, one cannot automatically assume
that a finding of PrP\BSE\ in a tissue means the tissue should be
considered infectious or should be considered an SRM. As noted by the
World Organization for Animal Health (OIE), the international standard-
setting organization for guidelines related to animal health:
The availability of experimental infectivity data has
significantly increased in recent years. During the same interval,
extremely sensitive tests have been developed, including those
employing highly sensitive transgenic mice strains and potentially
more sensitive laboratory PrP detection methods. With the
development of such highly sensitive methods, the probability of
detection of PrP\BSE\ in tissues that are not currently listed as
infectious is increasing. However, such findings need to be
considered in context, and their relevance to establishing risk to
consumers evaluated carefully when the quantity of PrP\BSE\ detected
is potentially below the limit of detection of intracerebral cattle
to cattle bioassay (OIE TAHSC, 2006).
Within USDA, APHIS and FSIS review and consider carefully, on an
ongoing basis, all BSE research regarding the definition of SRMs, as do
other countries that participate in OIE. International guidelines
regarding SRM definition and removal have not changed based on the
results of the studies noted above that report finding the presence of
the abnormal prion protein in various tissues. U.S. regulations
regarding SRM removal are consistent with international guidelines.
Prior to 2005, when the APHIS final rule on BSE minimal-risk
regions (70 FR 460-553, Docket No. 03-080-3) became effective, APHIS'
import regulations regarding BSE considered three categories of regions
with regard to BSE--(1) those in which BSE is known to exist, (2) those
that present an undue risk of BSE, and (3) all regions not listed in
either of the other two categories. Imports from BSE-affected regions
and those considered to present an undue risk are governed by the same
set of restrictions, including a prohibition on the importation of
meat, meat products, and edible products other than meat (except for
milk and milk products and gelatin under certain conditions). All other
regions were not subject to any import restrictions because of BSE.
Beginning in 2003, APHIS commenced a rulemaking process to update
our BSE regulations to reflect the latest scientific data and knowledge
of the disease. In a document published in the Federal Register on
November 4, 2003 (68 FR 62386-62405, Docket No. 03-080-1), APHIS
proposed to establish a category of regions that present a minimal risk
of introducing BSE into the United States via live ruminants and
ruminant products and byproducts, and to add Canada to this category.
The proposal also set forth conditions for the importation of certain
live ruminants and ruminant products and byproducts from BSE minimal-
risk regions. Among the conditions for the importation of meat from BSE
minimal-risk regions was that the meat be derived from bovines less
than 30 months of age when slaughtered. This age restriction was a
measure to guard against the importation of, or contamination of meat
through contact with, tissues other than meat that have the potential
of containing high levels of BSE infectivity.
On December 25, 2003, less than 2 weeks before the close of the
comment period for the proposed rule, a case of BSE in a dairy cow of
Canadian origin in Washington State was verified by an international
reference laboratory. Subsequently, both FSIS and FDA implemented
significant additional measures in the United States to protect human
health. In addition, APHIS commenced an enhanced BSE surveillance
program to determine the incidence of the disease in the United States.
The measures taken by FSIS included declaring SRMs to be inedible
and requiring their removal from cattle at slaughter. FSIS designated
as SRMs the brain, skull, eyes, trigeminal ganglia, spinal cord,
vertebral column (excluding the vertebrae of the tail, the transverse
process of the thoracic and lumbar vertebrae, and the wings of the
sacrum), and DRG of cattle 30 months of age or older, and the tonsils
and distal ileum of the small intestine of all cattle. To ensure
effective removal of the distal ileum, FSIS also required that the
entire small intestine be removed and be disposed of as inedible.\2\
FSIS also required all slaughtering and processing establishments to
develop, implement, and maintain written procedures for the removal,
segregation, and disposition of SRMS. Establishments were specifically
required to implement procedures to address the potential contamination
of edible materials with SRMs before, during, and after entry into the
establishment. FSIS did not restrict the age of cattle eligible for
slaughter, because the removal of SRMs effectively mitigates the BSE
risk to humans associated with cattle that pass both ante-mortem and
post-mortem inspections (i.e., apparently healthy cattle).
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\2\ On September 7, 2005, FSIS published in the Federal Register
an interim final rule that allowed for use as human food, under
certain conditions, beef small intestine, excluding the distal
ileum, derived from cattle slaughtered in official U.S.
establishments or in certified foreign establishments in countries
listed by FSIS in 9 CFR 327.2(b) as eligible to export meat products
to the United States.
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Pursuant to the Federal Meat Inspection Act, countries that export
meat to the United States must implement food safety requirements that
are equivalent to those in place in the United States. To be eligible
to export beef to the United States, a country must have in place a
system to effectively keep SRMs out of the production chain and to
prevent cross-contamination of beef with SRMs. FSIS has determined that
the SRM requirements implemented by Canada in July 2003 are equivalent
to FSIS' requirements. Additionally, FDA's feed ban prohibits most
mammalian protein, including ruminant protein, from entering the
ruminant feed chain in the United States.
On March 8, 2004, we published a document in the Federal Register
(69 FR 10633-10636, Docket No. 03-080-2) explaining the effects on our
proposed rule of the detection of BSE in the State of Washington in a
cow imported from Canada and of the additional measures taken by FSIS,
APHIS, and FDA. That document explained why the detection of an
imported BSE-infected cow did not alter the conclusions we had reached
in our original risk assessment. It explained further that, in fact,
the resulting additional measures put in place by FSIS provided a basis
for removing from the proposed provisions an age restriction on cattle
from which meat would be derived for export to the United States.
Accordingly, we proposed to allow the importation of beef derived from
cattle of any age. To give the public additional time to comment on the
proposal in light of these developments, we reopened and extended the
comment period for an additional 30 days.
On January 4, 2005, we published in the Federal Register (70 FR
460-553, Docket No. 03-080-3) a final rule that established the
criteria for BSE minimal-risk regions, listed Canada as a BSE minimal-
risk region, and specified importation requirements for live animals,
and meat products and byproducts. The final rule allowed the
importation of meat from bovines of any age, as we had proposed on
March 8, 2004. The final rule was scheduled to become effective on
March 7, 2005.\3\
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\3\ On March 2, 2005, Judge Richard F. Cebull of the U.S.
District Court for the District of Montana ordered that the
implementation of APHIS' January 4, 2005, final rule be
preliminarily enjoined. On July 14, 2005, the U.S. States Court of
Appeals for the Ninth Circuit ordered that the preliminary
injunction order be vacated and the case remanded to the District
Court.
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[[Page 54087]]
In January 2005, BSE was confirmed in two cows in Canada.
On March 11, 2005, APHIS published a document in the Federal
Register (70 FR 12112-12113, Docket No. 03-080-6) that, pursuant to an
announcement by the Secretary of Agriculture on February 9, 2005,
delayed the applicability of the provisions of the January 2005 final
rule as they applied to the importation from Canada of the following
commodities when derived from bovines 30 months of age or older when
slaughtered: (1) Meat, meat food products, and meat byproducts other
than liver; (2) whole or half carcasses; (3) offal; (4) tallow composed
of less than 0.15 percent insoluble impurities that is not otherwise
eligible for importation under 9 CFR 95.4(a)(1)(i); and (5) gelatin
derived from bones of bovines that is not otherwise eligible for
importation under 9 CFR 94.18(c).
In his February 9, 2005, announcement, the Secretary stated that
because ongoing investigations into the recent finds of BSE in Canada
in animals over 30 months of age were not complete, he felt it prudent
to delay the effective date for allowing imports of meat from bovines
30 months of age and over. He also indicated that the delay of
applicability would address concerns that the January 2005 final rule
allowed the importation of meat from bovines 30 months of age or older,
while continuing to prohibit the importation of live cattle 30 months
of age or older for processing in the United States. The Secretary
stated that the Department would consider and develop a plan--based on
the latest scientific information and with the protection of public and
animal health as the highest priority--to allow imports of live bovines
30 months of age or older.
In January 2005, an APHIS team visited Canada to evaluate the
epidemiology of the North American BSE cases that had been identified
at that time. This team concluded that the information available
suggested a localized exposure, based on the relatively small
geographical location, the temporal association, and the clustering of
cases. The team also evaluated the likelihood of higher-risk animal or
feed exposure to the United States at that time, and concluded that the
U.S. feed ban and other mitigations had effectively minimized the risk
of transmission or amplification of the BSE agent (USDA, 2005). In
addition, also in January 2005, USDA sent a team to Canada to assess
Canada's feed ban and its feed inspection program to determine whether
the control measures put in place by the Canadian Government were
achieving compliance with that country's regulations. APHIS conducted
an extensive review of the feed ban in Canada and concluded that Canada
has a robust inspection program, that overall compliance with the feed
ban in Canada was good, and that the feed ban was reducing the risk of
transmission of BSE in the Canadian cattle population (USDA, 2005a).
On January 9, 2007, we published a proposed rule in the Federal
Register (72 FR 1101-1129, Docket No. APHIS-2006-0041) to, among other
things, establish conditions for the importation from BSE minimal-risk
regions of live bovines for any use born on or after a date determined
by APHIS to be the date of effective enforcement of a ruminant-to-
ruminant feed ban in the region of export.\4\
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\4\ Requiring that live bovines exported to the United States
from BSE minimal-risk regions be born after the date of effective
enforcement of a ruminant-to-ruminant feed ban is consistent with
the standards of the World Organization for Animal Health (OIE) for
the exportation of live bovines from countries classified by the OIE
as having either a negligible or a controlled BSE risk. We consider
effective enforcement to have been achieved after completion of the
initial (or practical) period of implementation of a feed ban and
after sufficient time has elapsed to allow most feed products to
cycle through the system. The practical implementation period, which
begins when the regulations are initially put in place, can be
determined by evaluating implementation guidance and policies, such
as allowing grace periods for certain aspects of the industry. In
addition, the time necessary for initial education of industry and
training of inspectors must be considered. After the practical
implementation period is defined, we then consider the time
necessary subsequent to practical implementation to allow most feed
products to cycle through the system, given the management practices
in the country. Effective enforcement does not necessarily mean that
100 percent compliance with the feed ban requirements will be
achieved.
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We conducted an assessment of the risk to U.S. livestock of
allowing the importation of live bovines according to the provisions of
the proposed rule from Canada--currently the only region recognized as
a BSE minimal-risk region by APHIS. That risk assessment incorporated
and built on information from all of the previous analyses, including
the 2005 reports of the feed ban team and the epidemiological
investigation team. In the risk assessment, we evaluated both the
likelihood of ``release'' of the BSE agent into the United States and
the likelihood of susceptible animals being exposed, given such
release. We evaluated the pathways by which infected Canadian cattle,
if imported, might expose U.S. cattle to BSE, and the likelihood that
these pathways might lead to the establishment of the disease in the
U.S. cattle population. We concluded that the likelihood of BSE
exposure and establishment in the U.S. cattle population as a
consequence of imports under the proposed rule was negligible.
In our risk assessment, we explained that several steps must occur
for BSE to be transmitted to cattle in the United States from a live
bovine imported from another country. A BSE-infected bovine must be
imported into the United States; the infected bovine must die or be
slaughtered; tissues from that animal that contain the infectious agent
(i.e., the SRMs) must be sent to a rendering facility; the infectivity
present in these tissues must survive inactivation in the rendering
process; the resulting meat-and-bone meal containing the abnormal prion
protein must be incorporated into feed; and this feed must be fed to
cattle, in contravention of FDA regulations, at a level adequate to
infect the cattle. (The amount of infectious material required in feed
for cattle to become infected is dependent on the age of the cattle;
younger cattle are more susceptible to BSE and require less BSE-
contaminated feed to become infected (Arnold and Wilesmith, 2004)). We
explained in our risk assessment that some of the steps could occur in
parallel--i.e., without the occurrence of other steps--while others
would need to occur in series. Because the impact of any specific step
would depend on its relationship to other steps, its importance to the
likelihood of BSE transmission, and, in turn, the impact of disease
mitigation measures at each step, cannot be understood in isolation
from the rest of the pathway.
One component of our risk assessment was an estimate of the
prevalence of BSE in Canada, which was conducted using the same methods
as an earlier estimate of the prevalence of BSE in the United States.
The results of this prevalence estimate were then used to inform the
subsequent considerations and calculations in the risk assessment.
Because the prevalence was not zero--i.e., we concluded and
acknowledged that BSE is still present in Canada at low levels--the
risk assessment consequently assumed that infected animals could be
imported into the United States under the provisions of the proposed
rule. Even with this assumption, our conclusion that the risk of the
exposure of U.S. cattle and the establishment of BSE in the United
States was negligible remained unchanged.
On September 18, 2007, we published in the Federal Register (72 FR
53314-53379, Docket No. APHIS-2006-0041) a
[[Page 54088]]
final rule that adopted the changes to the regulations we had proposed
in January 2007. Additionally, the September 2007 final rule removed
the partial delay of applicability of the January 2005 final rule with
respect to meat and certain meat products and byproducts derived from
cattle over 30 months of age. In our September 2007 final rule, we
stated that, subsequent to implementation of the partial delay of
applicability, ``we [had] obtained additional information regarding all
aspects of the issues that prompted the delay of applicability and
[had] conducted additional analyses'' as indicated by the Secretary in
February 2005 to allow imports of live bovines 30 months of age or
older (72 FR 53316).
As we concluded in our September 2007 final rule, the risk
assessment for that final rule demonstrates the negligible BSE risk
from the importation of additional classes of live bovines, including
those 30 months of age or older. As explained previously, the risk of
transmission of BSE occurs when SRMs from infected cattle enter the
ruminant feed supply in contravention of current feed regulations.
Since the risk is tied to those tissues that contain infectivity, if
those tissues are excluded from import, the risk is mitigated. When
live cattle are imported, the potential exists that, after their death,
their SRMs could enter the ruminant feed supply. Even with this
potential, the conclusion of the risk assessment was that such imports
present a negligible risk of establishment of BSE in the United States.
As noted above, one of the requirements for the importation of meat
from bovines is that the SRMS be removed from the animals from which
the meat is derived. In other words, the SRMs are excluded from import
and would not even have the potential to enter the risk pathway in the
United States. Therefore, the conclusion of negligible risk related to
the importation of live older bovines gives further support to the
conclusion of the risk analysis conducted for our January 2005 final
rule regarding meat and meat products derived from bovines of any age
in BSE minimal-risk regions. Specifically, the risk is even lower for
the importation of meat and meat products than for live bovines.
The September 2007 final rule, which included the removal of the
partial delay of applicability of the provisions of the January 2005
rule relating to meat derived from cattle 30 months of age or older,
became effective on November 19, 2007.
On July 3, 2008, Judge Lawrence L. Piersol of the U.S. District
Court for the District of South Dakota, in response to a motion filed
in that Court, ordered USDA to provide the public with notice and a
further opportunity to comment on the provisions of our January 2005
final rule regarding the importation of beef from bovines 30 months of
age or older when slaughtered, to consider comments made by interested
parties, and to revise the rule as USDA deems necessary. In this
document, we are providing such notice and further opportunity for
comment. We will consider all comments that we receive by November 17,
2008.
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Authority: 7 U.S.C. 450, 7701-7772, and 8301-8317; 21 U.S.C. 136
and 136a; 31 U.S.C. 9701; 7 CFR 2.22, 2.80, and 371.4.
Done in Washington, DC, this 12th day of September 2008.
Cindy J. Smith,
Administrator, Animal and Plant Health Inspection Service.
[FR Doc. E8-21786 Filed 9-17-08; 8:45 am]
BILLING CODE 3410-34-P