[Federal Register: February 7, 2008 (Volume 73, Number 26)]
[Notices]
[Page 7298-7310]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07fe08-75]
-----------------------------------------------------------------------
DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
[Docket No. FDA-2008-D-0058]
Draft Compliance Policy Guide Sec. 555.320 Listeria
monocytogenes; Notice of Public Meeting
AGENCY: Food and Drug Administration, HHS.
ACTION: Notice of meeting.
-----------------------------------------------------------------------
SUMMARY: The Food and Drug Administration (FDA) is announcing a public
meeting to discuss a Draft Compliance Policy Guide Sec. 555.320
Listeria monocytogenes (the draft CPG) that provides guidance for FDA
staff on the agency's enforcement policy for L. monocytogenes in ready-
to-eat (RTE) foods that support growth of the organism and RTE foods
that do not support growth of the organism.
DATES: The meeting will be held on March 28, 2008, from 9 a.m. to 4:30
p.m. The closing date for requests to make an oral presentation is
March 7, 2008. The closing date for advance registration, for notifying
the contact person about a need for special accommodations due to a
disability, and for providing a brief description of an oral
presentation and
[[Page 7299]]
any written material for the presentation is March 21, 2008. Persons
wishing to park onsite should inform the contact person of their
request by March 24, 2008.
ADDRESSES: The meeting will be held at the Harvey W. Wiley Federal
Bldg., Food and Drug Administration, Center for Food Safety and Applied
Nutrition, 5100 Paint Branch Pkwy., College Park, MD, 20740-3835 (Metro
stop: College Park on the Green Line). Submit electronic registration
and requests to make an oral presentation to http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.cfsan.fda.gov/register.html.
Submit written or oral registration, requests to make an
oral presentation, written material for a presentation, and questions
in advance of the meeting to the contact person for registration (see
FOR FURTHER INFORMATION CONTACT). A transcript of the meeting will be
available for review at the Division of Dockets Management (HFA-305),
Food and Drug Administration, 5630 Fishers Lane, rm. 1061, Rockville,
MD.
FOR FURTHER INFORMATION CONTACT: For registration, requests for oral
presentation, submission of written material for the presentation, and
submission of questions in advance of the meeting: Isabelle Howes, U.S.
Department of Agriculture Graduate School, 600 Maryland Ave., SW.,
suite 270, Washington, DC 20024-2520, 202-314-4713, FAX: 202-479-6801,
e-mail: isabelle_howes@grad.usda.gov.
For general questions about the meeting, to request onsite parking,
or if you need special accommodations due to a disability: Juanita
Yates, Center for Food Safety and Applied Nutrition, Food and Drug
Administration, 5100 Paint Branch Pkwy., College Park, MD 20740, 301-
436-1731, e-mail: Juanita.Yates@fda.hhs.gov.
SUPPLEMENTARY INFORMATION:
I. Registration and Requests for Oral Presentations
Due to limited space and time, we encourage all persons who wish to
attend the meeting or to request an opportunity to make an oral
presentation to register in advance. We encourage you to register and
request an opportunity to make an oral presentation electronically, if
possible. You may also register orally or in writing by providing
registration information (including name, title, firm name, address,
telephone number, fax number, and e-mail address), requests to make an
oral presentation, and written material for the presentation to the
contact person for registration (see FOR FURTHER INFORMATION CONTACT).
II. Background
FDA has been working with its Federal, State, local, and
international food safety counterparts in an effort to reduce the
incidence of foodborne illness in the United States, including illness
caused by L. monocytogenes. As part of this effort, FDA is announcing
elsewhere in this issue of the Federal Register the availability of,
and requesting comment on, a draft CPG that provides guidance to FDA
staff on the agency's enforcement policy for L. monocytogenes in RTE
foods that support growth of the organism and in RTE foods that do not
support growth of the organism.
FDA is holding this public meeting to discuss and share information
about the enforcement policy in this draft CPG. Stakeholders will have
an opportunity to ask questions about the draft CPG and provide oral
comments on the draft CPG. Stakeholders may send questions in advance
to the contact person identified above (see FOR FURTHER INFORMATION
CONTACT). Any questions submitted in advance may be posted without
change to http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.fda.gov/ohrms/dockets/default.htm, including any
personal information provided.
III. Transcripts
A transcript of the meeting will be available for review at the
Division of Dockets Management (see ADDRESSES) between 9 a.m. and 4
p.m. Monday through Friday and on the Internet at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.fda.gov/ohrms/dockets/default.htm
, approximately 30 days after the hearing.
Written transcripts of the meeting may be requested in writing from the
Freedom of Information Office (HFI-35), Food and Drug Administration,
5600 Fishers Lane, rm. 6-30, Rockville, MD 20857, approximately 15
working days after the meeting at a cost of 10 cents per page.
IV. Background and Rationale for the Establishment of the Enforcement
Policy
A. Introduction
This document presents the background and rationale for the
establishment of an enforcement policy for L. monocytogenes in RTE
foods based on whether the food does, or does not, support its growth.
Under section 402(a)(1) of the Federal Food, Drug, and Cosmetic Act
(the act) (21 U.S.C. 342(a)(1)), a food shall be deemed to be
adulterated if it bears or contains any poisonous or deleterious
substance which may render it injurious to health, except that if the
substance is not an added substance such food shall not be considered
adulterated if the quantity of such substance in such food does not
ordinarily render it injurious to health. Courts have interpreted the
phrase ``injurious to health'' as encompassing protection of the health
of vulnerable subpopulations. See United States of America v. Lexington
Mill & Elevator Co., 232 U.S. 399, 411 (1914).\1\ L. monocytogenes is
an added deleterious substance in food. United States of America v.
Union Cheese Co., 902 F. Supp. 778, 786 (N.D. Ohio 1995).
---------------------------------------------------------------------------
\1\ See also, e.g., Young v. Community Nutrition Institute, 476
U.S. 974, 982-83 (1986) (citing to United States of America v.
Lexington Mill & Elevator Co. as ``discussing proper interpretation
of the language that became Sec. 342(a)'').
---------------------------------------------------------------------------
We are issuing for public comment a draft CPG that, when finalized,
would provide guidance for FDA staff as follows:
For RTE foods that support the growth of L. monocytogenes,
FDA may regard the food as adulterated within the meaning of section
402(a)(1) of the Act (21 U.S.C. 342(a)(1)) when L. monocytogenes is
present in the food, based on an analytical method that can detect 1.0
colony forming units (cfu) of L. monocytogenes per 25 grams (g) of food
(i.e., 0.04 cfu/g).
For RTE foods that do not support the growth of L.
monocytogenes, FDA may regard the food as adulterated within the
meaning of section 402(a)(1) of the act (21 U.S.C. 342(a)(1)) when L.
monocytogenes is present at or above 100 cfu/g of food.
B. Background on L. monocytogenes
L. monocytogenes is a pathogenic bacterium. Foods that are
contaminated with L. monocytogenes and consumed without thorough
cooking have been associated with a mild non-invasive illness with flu-
like symptoms (called listerial gastroenteritis) and a rare but
potential severe disease (called listeriosis). Listeriosis
predominately affects fetuses and neonates who are infected after the
mother is exposed to L. monocytogenes during pregnancy, the elderly,
and persons with weakened immune systems. Listeriosis is characterized
by a high case-fatality rate, ranging from 20 percent to 30 percent.
Most cases of human listeriosis occur sporadically--that is, in an
isolated manner without any apparent pattern. However, much of what is
known about the epidemiology of the disease has been derived from
outbreak-associated cases, in which there is an abrupt increase in
reports of the disease. Foods that have been implicated in sporadic
cases or outbreaks of listeriosis have been foods (including coleslaw,
fresh soft cheese made with
[[Page 7300]]
unpasteurized milk, frankfurters,\2\ deli meats, and butter) that are
RTE. (Ref. 1).
---------------------------------------------------------------------------
\2\ Some of the food categories discussed in this document
(e.g., frankfurters) are under the jurisdiction of the Food Safety
and Inspection Service (FSIS) of the U.S. Department of Agriculture
rather than FDA.
---------------------------------------------------------------------------
L. monocytogenes is widespread in the environment. It is found in
soil, water, sewage, and decaying vegetation. It has been isolated from
humans, domestic animals, raw agricultural commodities, and food
processing environments (particularly cool damp areas) (Refs. 2 through
4). Control of L. monocytogenes in the food processing environment has
been the subject of a number of scientific publications (Refs. 5
through 7). L. monocytogenes can survive longer under adverse
environmental conditions than many other vegetative bacteria that
present a food safety concern. L. monocytogenes tolerates high salt
concentrations (such as in nonchlorinated brine chiller solutions) and
survives frozen storage for extended periods. It is more resistant to
nitrite and acidity than many other foodborne pathogens. It also is
more resistant to heat than many other nonspore forming foodborne
pathogens, although it can be killed by heating procedures such as
those used to pasteurize milk\3\ (Ref. 8). Importantly, L.
monocytogenes can multiply slowly at refrigeration temperatures,
thereby challenging an important defense against foodborne pathogens--
i.e., refrigeration (Refs. 9 and 10).
---------------------------------------------------------------------------
\3\ Because normal pasteurization will effectively eliminate L.
monocytogenes, it is generally assumed that contamination of
products such as pasteurized fluid milk is the result of post-
pasteurization contamination (see Section V of Ref. 1, p. 170).
---------------------------------------------------------------------------
Some foods (such as ice cream and pickled fish) are characterized
by intrinsic or extrinsic factors\4\ that generally prevent the growth
of L. monocytogenes (i.e., they are ``listeristatic''), or are
processed to alter the normal characteristics of the food. For example,
it is well established (Refs. 10 and 12 through 14) that L.
monocytogenes does not grow when:
---------------------------------------------------------------------------
\4\ Intrinsic factors include chemical and physical factors that
are normally within the structure of the food, e.g., pH and water
activity. Extrinsic factors are those that refer to the environment
surrounding the food, e.g., storage temperature. Processing factors
are those that are deliberately applied to food to achieve improved
preservation, such as the addition of acid to lower pH (Ref. 11).
---------------------------------------------------------------------------
The pH of the food is less than or equal to 4.4;
The water activity of the food is less than or equal to
0.92; or
The food is frozen.
Foods may naturally have a pH or water activity that prevents
growth of L. monocytogenes or may be deliberately processed to achieve
those characteristics (e.g., by adding acid to deli-type salads to
bring the pH to less than or equal to 4.4). Listeristatic control
measures, such as some antimicrobial substances, can prevent L.
monocytogenes from growing in food (Ref. 10).\5\
---------------------------------------------------------------------------
\5\ Whether a particular antimicrobial substance is effective in
preventing the growth of L. monocytogenes in a given food generally
depends on a series of factors. Naturally occurring or added
antimicrobial substances can have an interactive or synergistic
effect with other parameters of the formulation, such as pH, water
activity, the presence of other preservatives, and processing
temperature. A concept known as the ``hurdle concept'' states that
several inhibitory factors (hurdles), while individually unable to
inhibit microorganisms, will, nevertheless, be effective in
combination (Refs. 10 and 15). For reasons such as these, whether
the addition of a particular antimicrobial substance to a particular
food is effective in preventing the growth of L. monocytogenes is a
case-by-case determination, based on available data and information.
However, a listeristatic control measure is generally considered to
be effective if growth studies show less than one log increase in
the number of L. monocytogenes during replicate trials with the food
of interest. For an example of how such studies are conducted, see
Reference 16.
---------------------------------------------------------------------------
Examples of RTE foods that generally are considered to not support
the growth of L. monocytogenes include:\6\
---------------------------------------------------------------------------
\6\ The examples in this document of foods that generally fall
within a given category do not include meat and poultry products
because such products are under the jurisdiction of FSIS. Unless
otherwise specified, the reference supporting the characterization
of the food as to whether it supports the growth of L. monocytogenes
is Appendix 8 in Reference 1.
---------------------------------------------------------------------------
Fish that are preserved by techniques such as drying,
pickling, and marinating;
Ice cream and other frozen dairy products;
Processed cheese (e.g., cheese foods, spreads, slices);
Cultured milk products (e.g., yogurt, sour cream,
buttermilk);
Hard cheeses (less than 39 percent moisture) (e.g.,
cheddar, colby, and parmesan);
Some deli-type salads, particularly those processed to a
pH less than 4.4 and those containing antimicrobial substances such as
sorbic acid/sorbates or benzoic acid/benzoates under conditions of use
documented to be effective in preventing the growth of L.
monocytogenes;
Some vegetables (such as carrots); and
Crackers, dry breakfast cereals, and other dry foods that
have water activity less than 0.92 (Ref. 10).
In contrast, other foods (such as milk and crabmeat) do not have
factors that prevent the growth of L. monocytogenes. These foods
support the growth of L. monocytogenes. Examples of RTE foods that
support the growth of L. monocytogenes include:
Milk;
High fat and other dairy products (e.g., butter and
cream);
Soft unripened cheeses (greater than 50 percent moisture)
(e.g., cottage cheese and ricotta cheese);
Cooked crustaceans (e.g., shrimp and crab);
Smoked seafood (e.g., smoked finfish and mollusks);
Raw seafood that will be consumed as sushi or sashimi;
Many vegetables (such as broccoli, cabbage and salad
greens);
Non-acidic fruit (such as melon, watermelon, and papaya)
(Ref. 17; and
Some deli-type salads and sandwiches (particularly those
containing seafood and those prepared at retail establishments without
the addition of antimicrobial substances).
Appendix 8 of Reference 1 lists some of the available information
on the growth of L. monocytogenes in specific foods, such as several
categories of cheese, that include some products that support growth as
well as other products that do not support growth. Although Appendix 8
of Reference 1 has very limited information about the growth of L.
monocytogenes in fruits, Table 3.3 in Reference 10 reports the pH of
many fruits. Table 3.3 in Reference 10 also reports the pH of many
vegetables. For example, Table 3.3 in Reference 10 reports that the pH
of honeydew melons is 6.3-6.7, the pH of limes is 1.8-2.0, the pH of
corn is 7.3, and the pH of cucumbers is 3.8.
C. FDA Activities Addressing L. monocytogenes in RTE Food
Beginning in 1980, a number of reports linked listeriosis outbreaks
with various RTE foods, including coleslaw (Ref. 18), pasteurized milk
(Ref. 19), and Mexican-style soft, white cheese (Ref. 20). In 1986, FDA
revised Compliance Policy Guide (CPG) Sec. 527.300 Pathogens in Dairy
Products (7106.08) to address L. monocytogenes (Ref. 21). CPG Sec.
527.300 provides guidance for initiating legal action in cases
involving dairy products found to be improperly pasteurized,
contaminated with pathogenic microorganisms, or prepared and packed
under insanitary conditions. One criterion for initiating legal action
is that analysis of the dairy product demonstrates that one or more
units is positive for L. monocytogenes and is confirmed. The specimen
charge recommended by CPG Sec. 527.300 when this criterion is met is
that the article is adulterated within the meaning of 21 U.S.C.
342(a)(1) in that it contains a pathogenic microorganism, namely L.
monocytogenes, which may render it injurious to health. See United
[[Page 7301]]
States of America v. Union Cheese Co., 902 F. Supp. 778, 786 (N.D. Ohio
1995) (holding that the ``presence of L. monocytogenes'' rendered
defendant's cheese products adulterated within the meaning of 21 U.S.C.
342(a)(1)). Consistent with the guidance in CPG Sec. 527.300 and with
the Union Cheese decision, we issued warning letters or sought
injunction when we detected L. monocytogenes in foods other than dairy
products, such as cut salad or smoked seafood (Ref. 22 and United
States of America v. Blue Ribbon Smoked Fish, Inc., 179 F. Supp. 2d 30
(E.D.N.Y. 2001)).\7\
---------------------------------------------------------------------------
\7\ We also have worked with firms who voluntarily decide to
recall one or more food products--e.g., when L. monocytogenes is
detected by regulatory authorities in the States. However, CPG Sec.
527.300 does not address product recalls.
---------------------------------------------------------------------------
A 1996 paper authored by FDA staff and entitled ``U.S. position on
Listeria monocytogenes in foods'' (Ref. 23) stated that, based on the
available scientific information, FDA considered detection of L.
monocytogenes in cooked, RTE foods to be a violation of section
402(a)(1) of the act, in that the food bears or contains an added
poisonous or deleterious substance which may render it injurious to
health. The authors stated that FDA had established a ``zero
tolerance'' for L. monocytogenes in cooked, RTE foods. The authors used
the term ``zero tolerance'' to indicate that FDA considered any
detectable level of L. monocytogenes in cooked, RTE foods to be
unacceptable from a public health perspective.
FDA uses an analytical method that can detect 1.0 cfu of L.
monocytogenes per 25 g of food to determine whether L. monocytogenes is
present in the food (i.e., 0.04 cfu/g) (Ref. 24).
D. Microbiological Limits Established Internationally for L.
monocytogenes
Some international entities are approaching the contamination of
foods with L. monocytogenes with different microbiological limits for
the food depending on whether the food does, or does not, support the
growth of L. monocytogenes. For example, Canada has adopted a three-
tiered enforcement policy for foods that may be contaminated with L.
monocytogenes (Ref. 25). The first tier addresses L. monocytogenes in
RTE foods that have been associated with an outbreak of listeriosis or
that were placed in the ``high risk'' category in a 2003 quantitative
risk assessment released by FDA and FSIS (Ref. 1). For foods in the
first tier, the presence of L. monocytogenes in the food is a Health 1
concern\8\ unless the measured pH or water activity, or data provided
by the manufacturer, demonstrates that the product does not support the
growth of L. monocytogenes. The second tier addresses L. monocytogenes
in RTE foods that are capable of supporting the growth of L.
monocytogenes and have a shelf life exceeding 10 days. For foods in the
second tier, the presence of L. monocytogenes in the food is a Health 2
concern unless data provided by the manufacturer demonstrate that the
product does not support the growth. The third tier addresses RTE
products that: (1) Support growth of L. monocytogenes, but have a shelf
life of equal to or less than 10 days, or (2) do not support growth of
L. monocytogenes. Foods in the third tier have the lowest priority, in
terms of inspection and compliance action, unless the product is
produced for, or targeted or distributed to, sensitive populations
(such as pregnant women or immunocompromised individuals). For foods in
the third tier, product containing greater than 100 cfu/g of L.
monocytogenes is a Health 2 concern, except that the presence of L.
monocytogenes in product that is produced for, or targeted or
distributed to, sensitive populations is considered a Health 1 or
Health 2 concern, based on consideration of all available information.
---------------------------------------------------------------------------
\8\ Under guidelines established by Health Canada for the
microbiological safety of food (Ref. 26), a Health 1 concern is one
in which action is taken to ensure that the product is no longer
sold and the population does not consume what they have at home. A
Health 2 concern is one in which action is taken to limit further
distribution of the product.
---------------------------------------------------------------------------
As another example, the Commission of the European Community has
established a directive that establishes a series of food safety
criteria for L. monocytogenes depending on the intended use of the food
and depending on whether the food remains under the control of the food
business operator or is in the market (Ref. 27). For example, the food
safety criterion for RTE foods intended for infants or for special
medical purposes is the presence of L. monocytogenes in the food,
regardless of whether the food supports its growth. The food safety
criterion for RTE foods that do not support the growth of L.
monocytogenes is 100 cfu/g. The food safety criterion for RTE foods
(other than those intended for infants or for special medical purposes)
that support the growth of L. monocytogenes is the presence of
detectable L. monocytogenes in the food before the food has left the
immediate control of the food business operator, or 100 cfu/g after the
food is in the market.
E. Establishing an Enforcement Policy for L. monocytogenes in RTE Foods
In 2001, FDA and USDA/FSIS, in consultation with the Centers for
Disease Control and Prevention of the United States Department of
Health and Human Services, requested comment on a draft quantitative
assessment (the 2001 Draft LmRA) (Ref. 28) of relative risk associated
with consumption of 20 categories of RTE foods that had a history of
contamination with L. monocytogenes, or that were implicated
epidemiologically with an outbreak or a sporadic case of listeriosis.
In 2003, FDA and USDA released their final risk assessment (the FDA/
FSIS LmRA) (Ref. 1), which includes revisions made after review of
comments received to the 2001 Draft LmRA. The FDA/FSIS LmRA (Ref. 1)
provides the scientific basis for the enforcement policy that is the
subject of the draft CPG.
In 2004, the Food and Agriculture Organization (FAO) and the World
Health Organization (WHO) of the United Nations (FAO/WHO) issued a Risk
Assessment of Listeria monocytogenes in Ready-to-Eat Foods (the FAO/WHO
LmRA) (Ref. 29). This risk assessment, prepared at the request of the
Codex Committee on Food Hygiene (CCFH) was intended to provide a
scientific basis for the development of guidelines for the control of
L. monocytogenes in foods by member countries. Representatives of FDA
participated in development of this FAO/WHO Risk Assessment, which
relied on data and information in the 2001 Draft FDA/FSIS LmRA. The
FAO/WHO LmRA provides additional scientific information that supports
the enforcement policy that is the subject of the draft CPG.
Both the FDA/FSIS LmRA and the FAO/WHO LmRA are quantitative risk
assessments that use mathematical modeling to estimate risk and assume
that individuals in a population may have varying susceptibility to
infection. The dose-response models developed in these risk assessments
are nonthreshold models that assume that a single cell has the
potential to infect and provoke a response in an individual (Ref. 30).
As a result, under these models the risk presented by foodborne L.
monocytogenes does not reach zero unless the number of L. monocytogenes
in a food serving is zero. Another consequence of the nonthreshold
model is that an increase in either the frequency of contamination
(percentage of food servings that are contaminated) or the level of
contamination (cfu/g in a contaminated food serving) is expected to
result in an increase in the
[[Page 7302]]
risk of listeriosis (see p. 138 of Part 5 of the FAO/WHO LmRA).
Conversely, a decrease in either the frequency of contamination or the
level of contamination is expected to result in a decrease in the risk
of listeriosis.
The FDA/FSIS LmRA and the FAO/WHO LmRA differ in aspects such as
focus (i.e., the questions that the risk assessments addressed),
modeling assumptions, source of data regarding exposure, and estimation
of serving size. For example, the FAO/WHO LmRA relies on the exposure
data in the 2001 Draft LmRA, whereas the FDA/FSIS LmRA relies on
revised exposure data that reflect modified food categories,
contamination data, growth data, and data on how long foods are stored
before consumption. As another example, the FDA/FSIS LmRA used
empirical distributions derived from consumer surveys to describe the
serving sizes in the food categories. These distributions were
expressed as a series of population percentiles of the amount of food
eaten per serving, weighted to reflect the consumption survey
demographics. In contrast, the FAO/WHO LmRA assumed a uniform serving
size of 31.6 g because this serving size both approximated a typical
serving size and simplified the calculations in that dose levels were
estimated in 0.5 log10 increments.
The FDA/FSIS LmRA and the FAO/WHO LmRA also differ in reported
output. For example, the FDA/FSIS LmRA provides information grouping
its results as a two-dimensional matrix with five overall risk
designations (very high, high, moderate, low, and very low) (see Figure
VII-1 in Section VII of the FDA/FSIS LmRA, p. 230), whereas the FAO/WHO
LmRA provides tables that report the annual incidence of listeriosis
estimated to be associated with specific ingested doses of L.
monocytogenes (see, e.g., Table 2.19 in Part 2, p. 58 and Table 5.3 in
Part 5, p. 137).
FAO/WHO characterize their dose-response model as a conservative
model that assumes maximum virulence of L. monocytogenes (see
discussions in Parts 2 and 5 of the FAO/WHO LmRA). One factor that FAO/
WHO identify as relevant to this characterization is their assumption
that the maximum dose to which L. monocytogenes could grow in a food is
10\7.5\ cfu/serving.\9\ In contrast, the dose-response model in the
FDA/FSIS LmRA assumed a distribution of virulent strains and that the
maximum dose to which L. monocytogenes could grow in a food is 10\10\
cfu/serving. The FAO/WHO LmRA includes a table (Table 2.19, see Part 2,
p. 58 of the FAO/WHO LmRA) that shows the impact of these different
assumptions about the maximum dose to which L. monocytogenes could grow
in a food on their estimate of the annual number of illnesses in the
susceptible population. Their least conservative assumption about the
maximum dose to which L. monocytogenes could grow in a food (i.e.,
10\10.5\ cfu/serving) is similar to the assumption used in the FDA/FSIS
LmRA (i.e., 10\10\ cfu/serving).
---------------------------------------------------------------------------
\9\ A more virulent strain would have the potential to cause
listeriosis with fewer cells than a less virulent strain.
---------------------------------------------------------------------------
Applying the exposure assessment and the dose response model in the
FDA/FSIS LmRA, we estimate that there would be no annual cases of
listeriosis in the total population if all servings of RTE foods were
at or below 10\5\ cfu/serving (corresponding to 10\3\ cfu/g or less for
a 100 g serving of food)\10\ (see Table 5 in Appendix 1 of this
document). We also estimate that the median number of cases of
listeriosis would be approximately 1 per year in the total population
from all the servings that are contaminated with 10\7\ cfu/serving or
less (corresponding to 10\5\ cfu/g or less for a 100 g serving of food)
and approximately 6 per year in the total population from all the
servings that are contaminated with up to and including 10\8\ cfu/
serving (corresponding to 10\6\ cfu/g for a 100 g serving of food).
Above doses of 10\8\ cfu/serving, the estimated median number of cases
of listeriosis in the total population per year increases
exponentially.
---------------------------------------------------------------------------
\10\ The data in the FDA/FSIS LmRA are reported in terms of cfu/
serving. However, it would not be practical from an operational
perspective to consider an enforcement policy concerning L.
monocytogenes in food in terms of cfu/serving, because each food
category has a different serving size. Instead, for purposes of an
enforcement policy, we would consider L. monocytogenes in terms of
cfu/g of food based on a uniform serving size. For operational
purposes, we selected a uniform serving size of 100 g because 100 g
approximates the median serving size for several of the food
categories that are consumed in relatively large amounts (see Table
III-3 in Section III, p. 35 of the FDA/FSIS LmRA). This is a
relatively conservative estimate of serving size and increases the
relative conservativeness of the enforcement policy.
---------------------------------------------------------------------------
These estimates are in line with the estimates reported by FAO/WHO
using their least conservative assumption regarding the maximum dose to
which L. monocytogenes could grow in a food (see Table 2.19 in Part 2,
p. 58 of the FAO/WHO LmRA). As can be seen from FAO/WHO Table 2.19,
FAO/WHO estimate that there would be no annual cases of listeriosis in
the susceptible population\11\ if all servings of RTE foods were at or
below 10\4.5\ cfu/serving (corresponding to 10\3\ cfu/g or less for a
31.6 g serving of food). FAO/WHO also estimate that the number of cases
of listeriosis would be approximately 1 per year in the susceptible
population from all the servings that are contaminated with 10\5.5\
cfu/serving or less (corresponding to 10\4\ cfu/g or less for a 31.6 g
serving of food) and approximately 6 per year in the susceptible
population from all the servings that are contaminated with up to and
including 10\6.5\ cfu/serving (corresponding to 10\5\ cfu/g for a 31.6
g serving of food). When the most conservative modeling assumptions are
used, FAO/WHO estimate that there would be no annual cases of
listeriosis in the susceptible population if all servings of RTE foods
were at or below 10\1.5\ cfu/serving (corresponding to 1 cfu/g or less
for a 31.6 g serving of food), that the number of cases of listeriosis
would be approximately 1 per year in the susceptible population from
all the servings that are contaminated with 10\2.5\ cfu/serving or less
(corresponding to 10 cfu/g or less for a 31.6 g serving of food), and
that the number of cases of listeriosis would be approximately 2 per
year in the susceptible population from all the servings that are
contaminated with up to and including 10\3.5\ cfu/serving
(corresponding to 10\2\ cfu/g for a 31.6 g serving of food).
---------------------------------------------------------------------------
\11\ FAO/WHO includes the elderly, infants, pregnant women and
immunocompromised patients in the susceptible population (see Part
1, p. 5 of the FAO/WHO LmRA).
---------------------------------------------------------------------------
The FDA/FSIS LmRA and other scientific information cited in that
document support a conclusion that RTE foods that support the growth of
L. monocytogenes are much more likely than other foods to be associated
with listeriosis. In the United States and other countries, both
outbreaks and sporadic cases of listeriosis have been overwhelmingly
associated with foods that support the growth of L. monocytogenes. The
FDA/FSIS LmRA estimates that only a small percent of contaminated
servings would be highly contaminated (see Table III-17 in Section III,
p. 75). We estimate that it is these higher dose exposures that are
responsible for most of the reported illnesses (See Table 5 in Appendix
1 of this document).
In contrast, the FDA/FSIS LmRA and other scientific information
cited in that document support a conclusion that RTE foods that do not
support the growth of L. monocytogenes present a low or very low risk
(as those terms are defined in the risk assessment) of listeriosis.\12\
The FDA/FSIS LmRA
[[Page 7303]]
estimates that foods that do not support the growth of L. monocytogenes
are associated, in total, with less than one case per billion servings
and less than one case per year (see Table V-6 in Section V, p. 133 of
the FDA/FSIS LmRA).
---------------------------------------------------------------------------
\12\ The FDA/FSIS LmRA estimates that Deli-type Salads (a
category of food defined in the risk assessment) present a moderate
risk of listeriosis. However, the data and analysis presented in the
FDA/FSIS LmRA do not distinguish between those Deli-type Salads that
support the growth of L. monocytogenes and those that do not support
the growth of L. monocytogenes. Regardless of this limitation, the
FDA/FSIS LmRA estimates that Deli-type Salads are associated with
less than one case of listeriosis per billion servings and less than
one case of listeriosis per year (see Figure V-6 in Section V, p.
133 of the FDA/FSIS LmRA). In addition, as shown in Table III-16 of
the FDA/FSIS LmRA (see Section III, p. 73) and Appendix 2 of this
document, it would be rare to find L. monocytogenes in Deli-type
Salads at greater than 100 cfu/g.
---------------------------------------------------------------------------
Because the difference in risk of listeriosis is linked to the
ability of a RTE food to support the growth of L. monocytogenes, it is
appropriate under a risk-based approach to regard RTE foods differently
based on whether the food does, or does not, support the growth of L.
monocytogenes.
Since RTE foods that do not support the growth can be expected to
have the same level of L. monocytogenes at the point of consumption
that they contain at the point when they leave the manufacturer, the
appropriate public health strategy is to establish an enforcement
policy that is based on the risk presented by consumption of various
doses of L. monocytogenes in these foods. The numerical value of the
microbiological limit used in a number of other countries for RTE foods
that do not support the growth of L. monocytogenes, and the numerical
value supported by the FDA/FSIS LmRA, is 100 cfu/g. FDA believes that
an enforcement policy aimed at maintaining L. monocytogenes below 100
cfu/g for such foods is protective of most vulnerable populations,
since these populations are included in the total population considered
in the FDA/FSIS LmRA and the susceptible population considered in the
FAO/WHO LmRA.\13\ Methods to enumerate L. monocytogenes are
available.\14\
---------------------------------------------------------------------------
\13\ The FAO/WHO LmRA estimates that individuals with serious
medical conditions (i.e,, transplant and dialysis patients and
individuals with certain cancers or AIDS), the perinatal population,
and the elderly have higher relative susceptibility than the general
population. See the discussion and tables in Part 5, pp. 140-142 of
the FAO/WHO LmRA. Appendix 9 of the FDA/FSIS LmRA notes that the
population estimated to have the greatest sensitivity (i.e.,
hospitalized transplant patients) may have experienced listeriosis
at levels as low as 5 to 60 cfu/g. However, these patients have a
temporary status in that the degree to which individual patients are
immunocompromised decreases as time passes relative to the clinical
procedure that they undergo. While in this temporary status, they
are under active medical care and their diets are carefully
controlled--e.g., they are unlikely to be consuming Preserved Fish.
In addition, it would be rare to find L. monocytogenes at greater
than 10 cfu/g in dairy products that do not support the growth of L.
monocytogenes (see Table III-16 of the FDA/FSIS LmRA in Section III,
p. 73 and Appendix 2 of this document).
\14\ E.g., the draft CPG advises FDA staff to use ISO 11290-
2:1998(E) ``Microbiology of food and animal feeding stuffs--
Horizontal method for the detection and enumeration of Listeria
monocytogenes--Part 2: Enumeration method'' as the method for
enumerating L. monocytogenes. ISO methods are available from the
International Organization for Standardization at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.iso.org/iso/en/ISOOnline.frontpage
.
---------------------------------------------------------------------------
In contrast, a RTE food that supports the growth of L.
monocytogenes may pose a risk to public health if it contains any
detectable L. monocytogenes, because the cfu/serving can reasonably be
expected to increase to a dose that is injurious to health during
storage periods after manufacture. Low levels after manufacture may
become high levels at the time of consumption. Therefore, the
appropriate public health strategy for RTE foods that support the
growth of L. monocytogenes is to regard the food as adulterated if L.
monocytogenes is present in the food. As noted above (see sections IV.A
and IV.C of this document), FDA uses an analytical method that can
detect 1.0 cfu of L. monocytogenes per 25 g of food (i.e., 0.04 cfu/g)
(Ref. 24).
The FDA/FSIS LmRA estimates that it would be rare to find L.
monocytogenes at greater than 100 cfu/g in RTE foods that do not
support its growth (see Table III-16 in the FDA/FSIS LmRA and Appendix
2 of this document). Thus, we expect that maintaining contamination
below 100 cfu/g is achievable for RTE foods that do not support the
growth of L. monocytogenes.
FDA anticipates that the public health benefits of this enforcement
policy include clarifying for FDA staff which foods support growth of
L. monocytogenes and, thus, helping to ensure that FDA resources are
focused on foods that are more likely to pose a greater risk to public
health. FDA anticipates that it may be able to increase the number of
samples that it periodically collects and tests for RTE foods that do
not support the growth of L. monocytogenes while it continues to focus
its inspection and outreach efforts on facilities manufacturing RTE
foods that support the growth of L. monocytogenes. States and local
governments could adopt this model for resource allocation. The policy
may also indirectly lead to other public health benefits, such as
verification strategies and reformulation of some RTE foods (e.g.,
through addition of antimicrobials, manipulation of pH, or other means)
so that they do not support the growth of L. monocytogenes.
V. References
We have placed the following references on display in the Division
of Dockets Management (see ADDRESSES). You may see them between 9 a.m.
and 4 p.m., Monday through Friday. FDA has verified the Web site
addresses, but FDA is not responsible for any subsequent changes to Web
sites after this document publishes in the Federal Register.
1. U.S. Food and Drug Administration and U.S. Food Safety and
Inspection Service, ``Quantitative Assessment of the Relative Risk
to Public Health from Foodborne Listeria monocytogenes Among
Selected Categories of Ready-to-Eat Foods,'' 2003. Available in
Docket No. 1999N-1168, vols. 23 through 28, and at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.foodsafety.gov/~dms/lmr2-toc.html.
Cited page numbers refer to
the Portable Document File (PDF) version of the document on the Web.
2. National Advisory Committee on Microbiological Criteria for
Foods (NACMCF), ``Listeria monocytogenes: Recommendations by the
National Advisory Committee on Microbiological Criteria for Foods,''
International Journal of Food Microbiology, vol. 14, pp. 185-246,
1991. Available in Docket No. 1999N-1168, vol. 0015 bkg1 (12 of 17),
Tab 287.
3. Fenlon, D. R., J. Wilson, and W. Donachie, ``The Incidence
and Level of Listeria monocytogenes Contamination of Food Sources at
Primary Production and Initial Processing,'' Journal of Applied
Bacteriology, vol. 81, pp. 641-650, 1996. Available in Docket No.
1999N-1168, vol. 0011 bkg1 (08 of 17), Tab 134.
4. Fenlon, D. R., ``Listeria monocytogenes in the Natural
Environment,'' Listeria, Listeriosis, and Food Safety, 2d ed., pp.
21-37 (E. T. Ryser and E. H. Marth, editors), Food Science and
Technology, New York, Marcel Dekker, Inc., 1999. Available in Docket
No. 1999N-1168, vol. 0009 bkg1 (06 of 17), file name bkg0001--5--
a.pdf.
5. Tompkin, R. B., ``Control of Listeria monocytogenes in the
Food Processing Environment,'' Journal of Food Protection, vol. 65,
pp. 709-725, 2002.
6. Moretro, T. and S. Lansgrund, ``Listeria monocytogenes:
Biofilm Formation and Persistence in Food Processing Environments,''
Biofilms, vol. 1, pp. 107-121, 2004.
7. Gall, K., V. N. Scott, R. Collette, et al., ``Implementing
Targeted Good Manufacturing Practices and Sanitation Procedures to
Minimize Listeria Contamination of Smoked Seafood Products,'' Food
Protection Trends, vol. 24, No. 5, pp. 302-315, 2004.
8. Doyle, M. E., A. S. Mazzotta, T. Wang, et al., ``Heat
Resistance of Listeria monocytogenes,'' Journal of Food Protection,
vol. 64, No. 3, pp. 410-429, 2001.
9. Lou, Y. and A. E. Yousef, ``Characteristics of Listeria
monocytogenes Important to Food Processors,'' Listeria, Listeriosis,
and Food Safety, 2d ed., pp. 131-224 (E. T. Ryser and E. H. Marth,
editors), Food Science and Technology, New York, Marcel Dekker,
Inc., 1999. Available in
[[Page 7304]]
Docket No. 1999N-1168, vol. 0014 bkg1 (11 of 17), Tab 245.
10. Institute of Food Technologists, IFT/FDA Contract No. 223-
98-2333, ``Evaluation and Definition of Potentially Hazardous
Foods,'' 2001. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.cfsan.fda.gov/~comm/ift4-toc.html.
Accessed and printed on April 6, 2007.
11. Russell, N. J. and G. W. Gould, ``Major Preservation
Technologies,'' Food Preservatives, 2d ed., p. 15 (N. J. Russell and
G. W. Gould, editors), Springer Publishing Co., New York, 2003.
12. Sorrells, K. M., D. C. Enigl, and J. R. Hatfield, ``Effect
of pH, Acidulant, Time, and Temperature on the Growth and Survival
of Listeria monocytogenes,'' Journal of Food Protection, vol. 52,
No. 8, pp. 571-573, 1989.
13. Petran, R. L. and E. A. Zottola, ``A Study of Factors
Affecting Growth and Recovery of Listeria monocytogenes Scott A,''
Journal of Food Science, vol. 54, No. 2, pp. 458-460, 1989.
14. Tienungoon, S., D. A. Ratkowsky, T. A. McMeekin, et al.,
``Growth Limits of Listeria monocytogenes as a Function of
Temperature, pH, NaCl, and Lactic Acid,'' Applied and Environmental
Microbiology, vol. 66, No. 11, pp. 4979-4987, 2000.
15. Leistner, L., ``Principles and Applications of Hurdle
Technology,'' New Methods of Food Preservation (G. W. Gould,
editor), London: Blackie Academic & Professional, pp. 1-21, 1995.
16. Scott, V. N., K. M. J. Swanson, T. A. Freier, et al.,
``Guidelines for Conducting Listeria monocytogenes Challenge Testing
of Foods,'' Food Protection Trends, vol. 25, No. 11, pp. 818-825,
2005.
17. Penteado, A. L. and M. F. F. Leitao, ``Growth of Listeria
monocytogenes in Melon, Watermelon and Papaya Pulps,'' International
Journal of Food Microbiology, vol. 92, pp. 89-94, 2004.
18. Schlech, W. F., III, P. M. Lavigne, R. A. Bortolussi, et
al., ``Epidemic Listeriosis: Evidence for Transmission by Food,''
Medical Intelligence, vol. 308, pp. 203-206, 1983. Available in
Docket No. 1999N-1168, vol. 0018 bkg1 (15 of 17), Tab 363.
19. Fleming, D. W., S. L. Cochi, K. L. MacDonald, et al.,
``Pasteurized Milk as a Vehicle of Infection in an Outbreak of
Listeriosis,'' New England Journal of Medicine, vol. 312, pp. 404-
407, 1985. Available in Docket No. 1999N-1168, vol. 0011 bkg1 (08 of
17), Tab 139.
20. Linnan, M. J., L. Mascola, X. D. Lou, et al., ``Epidemic
Listeriosis Associated with Mexican-Style Cheese,'' New England
Journal of Medicine, vol. 3, No. 19, pp. 823-828, 1988. Available in
Docket No. 1999N-1168, vol. 0014 bkg1 (11 of 17), Tab 241.
21. Compliance Policy Guide Sec. 527.300 Pathogens in Dairy
Products (CPG 7106.08). Accessed and printed on April 8, 2007. FDA
makes the most recent edition of the CPG available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.fda.gov/ora/compliance_ref/cpg/cpgfod/cpg527-300.html.
When a
CPG is revised, previous editions are no longer available on the
Internet.
22. Letter from J. H. Rahto of FDA, Minneapolis District Office
to Bradley V. Beckman, Custom Cuts Co., March 5, 1999. Available at
http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.fda.gov/foi/warning_letters/archive/m2438n.pdf. Accessed
and printed on September 30, 2005.
23. Shank, F. R., E. L. Elliot, K. Wachsmuth, et al., ``U.S.
Position on Listeria monocytogenes in Foods,'' Food Control, vol. 7,
No. 415, pp. 229-234, 1996. Available in Docket No. 1999N-1168, vol.
0018 bkg1 (15 of 17), Tab 374.
24. U.S. Food and Drug Administration, Bacteriological
Analytical Manual Online, Chapter 10--``Listeria monocytogenes,''
``Detection and Enumeration of Listeria monocytogenes in Foods,''
2003. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.cfsan.fda.gov/~ebam/bam-10.html.
Accessed and printed on April 10, 2007.
25. Health Canada, ``Policy on Ready-to-Eat Foods Contaminated
with Listeria monocytogenes,'' 2004. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.hc-sc.gc.ca/fn-an/alt_formats/hpfb-dgpsa/pdf/legislation/policy_listeria_monocytogenes_politique_toc_e.pdf.
Accessed and printed
d printed
26. Health Canada, ``Health Products and Food Branch (HPFB)
Standards and Guidelines for Microbiological Safety of Food--An
Interpretive Summary,'' 2006. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.hc-sc.gc.ca/fn-an/res-rech/analy-meth/microbio/volume1/intsum-somexp_e.html.
Accessed and printed on October 11, 2007.
27. Commission of the European Communities, ``Commission
Regulation (EC) No 2073/2005 of 15 November 2005 on Microbiological
Criteria for Foodstuffs,'' Official Journal of the European Union,
22.12.2005 L338/1-L338-26, 2005. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://europa.eu.int/eur-lex/lex/LexUriServ/site/en/oj/2005/l_338/l_33820051222en00010026.pdf.
Accessed and printed on May 10, 2007.
28. U.S. Food and Drug Administration and U.S. Food Safety and
Inspection Service, ``Draft Assessment of the Relative Risk to
Public Health from Foodborne Listeria monocytogenes Among Selected
Categories of Ready-to-Eat Foods,'' 2001. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.foodsafety.gov/~dms/lmrisk.html.
Accessed and printed on April
10, 2007.
29. Food and Agriculture Organization and World Health
Organization, ``Risk Assessment of Listeria monocytogenes in Ready-
to-Eat Foods,'' Microbiological Risk Assessment Series No. 5.
Technical Report, 2004. Available at http://frwebgate.access.gpo.gov/cgi-bin/leaving.cgi?from=leavingFR.html&log=linklog&to=http://www.who.int/foodsafety/publications/micro/mra_listeria/en/index.html.
Accessed and printed
on May 10, 2007.
30. Haas, C. N., ``Estimation of Risk Due to Low Doses of
Microorganisms: A Comparison of Alternative Methodologies,''
American Journal of Epidemiology, vol. 118, No. 4, pp. 573-582,
1983.
Appendix 1.--Data Output and Calculations Relevant to the Annual
Incidence of Listeriosis Estimated in The FDA/FSIS LMRA
Table IV-12 of the FDA/FSIS LmRA (Section IV, p. 110) reports the
relationship between the dose of L. monocytogenes (in cfu/serving) and
the response (as the estimated median mortality rate per serving) for
each of three age-based national population groups. The three
population groups are the elderly population (60 years and older),
perinatal population (prenatal and neonatal), and the remaining
population (designated the intermediate-aged).
We took the output data of the model used in the FDA/FSIS LmRA and
re-tabulated the data to show our estimates of the annual number of
cases of listeriosis in the elderly population, the intermediate-age
population, and the neonatal population, as well as in the total
population, as a function of the ingested dose (in colony forming
units, i.e., cfu) per serving. Tables 1 through 4 report that output
data.
Table 1 reports the estimated ascending cumulative percentage of
contaminated food servings consumed annually by the elderly population
at a series of doses (in cfu/serving) and the estimated ascending
cumulative percentage of illnesses in the elderly population. The data
are reported at the 5th, 50th (median), and 95th percentiles. Tables 2
through 4 report these data for the intermediate-age, neonatal, and
total populations, respectively.
Table IV-11 of the FDA/FSIS LmRA (Section IV, p. 105) reports the
estimated total number of illnesses for each population on an annual
basis as follows:
Elderly population: 1159
Intermediate-age population: 702
Neonatal population: 216
Total population: 2078
For each population, we calculated the incremental increase in the
estimated percentage of contaminated servings and the incremental
increase in the estimated percentage of illnesses. We then multiplied
the estimated incremental percentage of illnesses by the estimated
total number of illnesses for that population to obtain an estimate of
the number of listeriosis cases per year for each dose. Table 5 reports
the 50th percentile (i.e., median) calculated estimates of the annual
number of cases of listeriosis in the elderly population, the
intermediate-age population, and the neonatal population, as well as in
the total population, as a function of the ingested dose per serving
(i.e., cfu/serving). Table 5 also shows the calculated level (in cfu/g)
corresponding to a 100 g serving size.
[[Page 7305]]
Table 1.--Output from the Model in the FDA/FSIS LmRA Elderly Population
----------------------------------------------------------------------------------------------------------------
Estimated Servings (Cumulative Estimated Illnesses (Cumulative
Dose (cfu/serving) Percentage)\a\ Percentage)\b\
----------------------------------------------------------------------------------------------------------------
0 97.91% (92.85%, 98.72%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-4\ 97.92% (92.85%, 98.72%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-4\ 97.92% (92.86%, 98.73%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-3\ 97.93% (92.86%, 98.74%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-3\ 97.94% (92.87%, 98.75%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-2\ 97.95% (92.88%, 98.76%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-2\ 97.96% (92.90%, 98.77%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.1 97.99% (92.93%, 98.80%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.32 98.04% (92.99%, 98.85%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 98.30% (93.27%, 99.03%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 98.70% (93.99%, 99.29%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
10 99.04% (95.02%, 99.51%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
31.6 99.30% (95.96%, 99.67%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
100 99.48% (96.74%, 99.784) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
316 99.61% (97.40%, 99.86%) < 0.01% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1000 99.71% (97.95%, 99.90%) < 0.01% (0.00%, 0.010%)
----------------------------------------------------------------------------------------------------------------
3162 99.79% (98.40%, 99.93%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
10000 99.84% (98.78%, 99.95%) < 0.01% (0.00%, 0.02%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\4\ 99.88% (99.09%, 99.97%) < 0.01% (0.00%, 0.04%)
----------------------------------------------------------------------------------------------------------------
1 x 10\5\ 99.90% (99.33%, 99.98%) < 0.01% (0.00%, 0.08%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\5\ 99.92% (99.51%, 99.98%) 0.01% (0.00%, 0.15%)
----------------------------------------------------------------------------------------------------------------
1 x 10\6\ 99.94% (99.63%, 99.99%) 0.02% (0.00%, 0.30%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\6\ 99.95% (99.74%, 99.99%) 0.05% (0.00%, 0.65%)
----------------------------------------------------------------------------------------------------------------
1 x 10\7\ 99.96% (99.83%, 99.99%) 0.12% (0.00%, 1.60%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\7\ 99.97% (99.91%, 99.99%) 0.25% (0.00%, 3.00%)
----------------------------------------------------------------------------------------------------------------
1 x 10\8\ 99.97% (99.94%, > 99.99%) 0.56% (0.00%, 4.57%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\8\ 99.98% (99.96%, > 99.99%) 1.41% (0.00%, 7.96%)
----------------------------------------------------------------------------------------------------------------
1 x 10\9\ 99.98% (99.97%, > 99.99%) 2.85% (0.05%, 13.60%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\9\ 99.99% (99.98%, > 99.99%) 10.27% (0.62%, 45.11%)
----------------------------------------------------------------------------------------------------------------
1 x 10\10\ 100% (99.99%, 100%) 45.74% (8.83%, 86.80%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\10\ 100% (> 99.99%, 100%) 85.28% (46.57%, 96.54%)
----------------------------------------------------------------------------------------------------------------
1 x 10\11\ 100% (> 99.99%, 100%) 97.23% (79.31%, 100%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\11\ 100% (100%, 100%) 100% (94.58%, 100%)
----------------------------------------------------------------------------------------------------------------
1 x 10\12\ 100% (100%, 100%) 100% (100%, 100%)
----------------------------------------------------------------------------------------------------------------
\a\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
\b\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
[[Page 7306]]
Table 2.--Output from the Model in the FDA/FSIS LmRA Intermediate-Aged Population
----------------------------------------------------------------------------------------------------------------
Estimated Servings (Cumulative Estimated Illnesses (Cumulative
Dose (cfu/serving) Percentage)\a\ Percentage)\b\
----------------------------------------------------------------------------------------------------------------
0 97.83% (94.30%, 98.70%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-4\ 97.84% (94.31%, 98.71%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-4\ 97.85% (94.33%, 98.73%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-3\ 97.87% (94.35%, 98.74%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-3\ 97.89% (94.37%, 98.76%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-2\ 97.91% (94.39%, 98.78%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-2\ 97.93% (94.40%, 98.79%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.1 97.96% (94.43%, 98.81%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.32 98.01% (94.47%, 98.86%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 98.27% (94.72%, 99.04%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 98.64% (95.35%, 99.30%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
10 98.97% (96.15%, 99.51%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
31.6 99.22% (96.86%, 99.67%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
100 99.41% (97.51%, 99.77%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
316 99.55% (98.02%, 99.84%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
1000 99.66% (98.45%, 99.89%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
3162 99.74% (98.79%, 99.92%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
10000 99.80% (99.07%, 99.94%) < 0.01% (0.00%, 0.02%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\4\ 99.84% (99.29%, 99.96%) < 0.01% (0.00%, 0.03%)
----------------------------------------------------------------------------------------------------------------
1 x 10\5\ 99.87% (99.46%, 99.97%) < 0.01% (0.00%, 0.05%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\5\ 99.90% (99.60%, 99.98%) 0.01% (0.00%, 0.10%)
----------------------------------------------------------------------------------------------------------------
1 x 10\6\ 99.92% (99.70%, 99.98%) 0.02% (0.00%, 0.19%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\6\ 99.93% (99.78%, 99.99%) 0.04% (0.00%, 0.41%)
----------------------------------------------------------------------------------------------------------------
1 x 10\7\ 99.95% (99.86%, 99.99%) 0.09% (0.00%, 0.97%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\7\ 99.95% (99.90%, 99.99%) 0.20% (0.00%, 1.81%)
----------------------------------------------------------------------------------------------------------------
1 x 10\8\ 99.96% (99.93%, 100%) 0.45% (0.00%, 2.94%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\8\ 99.97% (99.95%, 100%) 1.19% (0.00%, 5.24%)
----------------------------------------------------------------------------------------------------------------
1 x 10\9\ 99.98% (99.96%, 100%) 2.29% (0.00%, 10.06%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\9\ 99.99% (99.97%, 100%) 8.59% (0.10%, 42.98%)
----------------------------------------------------------------------------------------------------------------
1 x 10\10\ 100% (99.98%, 100%) 43.15% (5.55%, 86.92%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\10\ 100% (> 99.99%, 100%) 85.13% (36.41%, 96.46%)
----------------------------------------------------------------------------------------------------------------
1 x 10\11\ 100% (> 99.99%, 100%) 97.23% (72.09%, 100%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\11\ 100% (100%, 100%) 100% (94.14%, 100%)
----------------------------------------------------------------------------------------------------------------
1 x 10\12\ 100% (100%, 100%) 100% (100%, 100%)
----------------------------------------------------------------------------------------------------------------
\a\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
\b\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
[[Page 7307]]
Table 3.--Output from the Model in the FDA/FSIS LmRA Neonatal Population
----------------------------------------------------------------------------------------------------------------
Estimated Servings (Cumulative Estimated Illnesses (Cumulative
Dose (cfu/serving) Percentage)\a\ Percentage)\b\
----------------------------------------------------------------------------------------------------------------
0 97.90% (94.56%, 98.74%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-4\ 97.91% (94.57%, 98.75%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-4\ 97.92% (94.58%, 98.77%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-3\ 97.94% (94.59%, 98.79%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-3\ 97.96% (94.61%, 98.80%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-2\ 97.98% (94.62%, 98.81%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-2\ 98.00% (94.64%, 98.83%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.1 98.03% (94.66%, 98.85%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.32 98.08% (94.72%, 98.90%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 98.33% (94.97%, 99.07%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 98.68% (95.57%, 99.33%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
10 99.01% (96.31%, 99.52%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
31.6 99.24% (97.01%, 99.67%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
100 99.43% (97.63%, 99.78%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
316 99.57% (98.11%, 99.84%) < 0.01% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1000 99.67% (98.52%, 99.89%) < 0.01% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3162 99.75% (98.85%, 99.92%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
10000 99.81% (99.11%, 99.95%) < 0.01% (0.00%, 0.03%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\4\ 99.85% (99.32%, 99.96%) < 0.01% (0.00%, 0.06%)
----------------------------------------------------------------------------------------------------------------
1 x 10\5\ 99.88% (99.48%, 99.97%) < 0.01% (0.00%, 0.15%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\5\ 99.90% (99.62%, 99.98%) 0.01% (0.00%, 0.35%)
----------------------------------------------------------------------------------------------------------------
1 x 10\6\ 99.92% (99.71%, 99.98%) 0.02% (0.00%, 0.71%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\6\ 99.94% (99.79%, 99.99%) 0.06% (0.00%, 1.53%)
----------------------------------------------------------------------------------------------------------------
1 x 10\7\ 99.95% (99.86%, 99.99%) 0.13% (0.00%, 3.26%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\7\ 99.96% (99.91%, 99.99%) 0.27% (0.00%, 5.81%)
----------------------------------------------------------------------------------------------------------------
1 x 10\8\ 99.97% (99.94%, 99.99%) 0.61% (< 0.01%, 8.72%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\8\ 99.97% (99.95%, > 99.99%) 1.49% (0.02%, 13.16%)
----------------------------------------------------------------------------------------------------------------
1 x 10\9\ 99.98% (99.96%, > 99.99%) 2.96% (0.19%, 20.08%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\9\ 99.99% (99.97%, > 99.99%) 11.09% (0.96%, 51.41%)
----------------------------------------------------------------------------------------------------------------
1 x 10\10\ > 99.99% (99.98%, > 99.99%) 52.05% (11.25%, 90.05%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\10\ > 99.99% (> 99.99%, 100%) 89.24% (56.05%, 97.60%)
----------------------------------------------------------------------------------------------------------------
1 x 10\11\ 100% (> 99.99%, 100%) 98.07% (88.20%, 100%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\11\ 100% (100%, 100%) 100% (96.51%, 100%)
----------------------------------------------------------------------------------------------------------------
1 x 10\12\ 100% (100%, 100%) 100% (100%, 100%)
----------------------------------------------------------------------------------------------------------------
\a\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
\b\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
[[Page 7308]]
Table 4.--Output from the Model in the FDA/FSIS LmRA Total Population
----------------------------------------------------------------------------------------------------------------
Estimated Illnesses (Cumulative
Dose (cfu/serving) Estimated Servings (Cumulative Percentage) Percentage)
----------------------------------------------------------------------------------------------------------------
0 97.85% (94.02%, 98.69%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-4\ 97.86% (94.03%, 98.71%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-4\ 97.87% (94.05%, 98.72%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-3\ 97.89% (94.06%, 98.74%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-3\ 97.91% (94.08%, 98.75%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 x 10\-2\ 97.92% (94.09%, 98.77%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\-2\ 97.93% (94.11%, 98.78%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.1 97.96% (94.14%, 98.80%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
0.32 98.01% (94.20%, 98.85%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1 98.27% (94.44%, 99.04%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
3.16 98.65% (95.11%, 99.30%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
10 98.98% (95.92%, 99.51%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
31.6 99.23% (96.67%, 99.67%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
100 99.42% (97.36%, 99.77%) 0.00% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
316 99.56% (97.89%, 99.85%) < 0.01% (0.00%, < 0.01%)
----------------------------------------------------------------------------------------------------------------
1000 99.67% (98.35%, 99.89%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
3162 99.75% (98.73%, 99.92%) < 0.01% (0.00%, 0.01%)
----------------------------------------------------------------------------------------------------------------
10000 99.80% (99.01%, 99.95%) < 0.01% (0.00%, 0.02%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\4\ 99.85% (99.25%, 99.96%) < 0.01% (0.00%, 0.04%)
----------------------------------------------------------------------------------------------------------------
1 x 10\5\ 99.88% (99.43%, 99.97%) < 0.01% (0.00%, 0.08%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\5\ 99.90% (99.58%, 99.98%) 0.01% (0.00%, 0.14%)
----------------------------------------------------------------------------------------------------------------
1 x 10\6\ 99.92% (99.69%, 99.98%) 0.02% (0.00%, 0.29%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\6\ 99.94% (99.77%, 99.99%) 0.05% (0.00%, 0.66%)
----------------------------------------------------------------------------------------------------------------
1 x 10\7\ 99.95% (99.85%, 99.99%) 0.12% (0.00%, 1.64%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\7\ 99.96% (99.91%, 99.99%) 0.25% (0.00%, 2.75%)
----------------------------------------------------------------------------------------------------------------
1 x 10\8\ 99.97% (99.93%, 99.99%) 0.55% (< 0.01%, 4.20%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\8\ 99.97% (99.95%, > 99.99%) 1.39% (< 0.01%, 7.33%)
----------------------------------------------------------------------------------------------------------------
1 x 10\9\ 99.98% (99.96%, > 99.99%) 2.73% (0.05%, 12.32%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\9\ 99.99% (99.97%, > 99.99%) 9.94% (0.58%, 44.23%)
----------------------------------------------------------------------------------------------------------------
1 x 10\10\ > 99.99% (99.98%, > 99.99%) 45.52% (8.21%, 86.55%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\10\ > 99.99% (> 99.99%, 100%) 85.45% (44.90%, 96.46%)
----------------------------------------------------------------------------------------------------------------
1 x 10\11\ 100% (> 99.99%, 100%) 97.18% (77.62%, 100%)
----------------------------------------------------------------------------------------------------------------
3.16 x 10\11\ 100% (100%, 100%) 100% (94.01%, 100%)
----------------------------------------------------------------------------------------------------------------
1 x 10\12\ 100% (100%, 100%) 100% (100%, 100.)
----------------------------------------------------------------------------------------------------------------
\a\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
\b\ Reported as the median (50th percentile), with the 5th and 95th percentiles in parentheses.
[[Page 7309]]
Table 5.--Annual Incidence of Listeriosis in the National Population Estimated Using the Model in the FDA/FSIS
LmRA (50th Percentile)
----------------------------------------------------------------------------------------------------------------
Corresponding Level Estimated Number of Cases of Listeriosis Per Year (50th Percentile)
Dose (cfu/ (cfu/g) Assuming a ---------------------------------------------------------------------------
serving) 100 g serving Elderly Intermediate-Age Neonatal Total Population
----------------------------------------------------------------------------------------------------------------
0 0 0 0 0 0
----------------------------------------------------------------------------------------------------------------
1 0.01 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
10 0.1 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
100 1 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
316 3.16 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
1,000 10 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
3,160 31.6 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
10,000 100 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
31,600 316 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
100,000 1,000 0.0 0.0 0.0 0.1
----------------------------------------------------------------------------------------------------------------
316,000 3,160 0.1 0.0 0.0 0.1
----------------------------------------------------------------------------------------------------------------
1,000,000 10\4\ 0.1 0.1 0.0 0.3
----------------------------------------------------------------------------------------------------------------
3,160,000 31,600 0.4 0.2 0.1 0.6
----------------------------------------------------------------------------------------------------------------
10\7\ 10\5\ 0.8 0.4 0.2 1.4
----------------------------------------------------------------------------------------------------------------
3.16 x 10\7\ 316,000 1.5 0.7 0.3 2.6
----------------------------------------------------------------------------------------------------------------
10\8\ 10\6\ 3.6 1.8 0.7 6.3
----------------------------------------------------------------------------------------------------------------
3.16 x 10\8\ 3.16 x 10\6\ 9.9 5.2 1.9 17.5
----------------------------------------------------------------------------------------------------------------
10\9\ 10\7\ 16.7 7.7 3.2 27.8
----------------------------------------------------------------------------------------------------------------
3.16 x 10\9\ 3.16 x 10\7\ 86.0 44.2 17.6 149.8
----------------------------------------------------------------------------------------------------------------
10\10\ 10\8\ 411.1 242.6 88.5 739.4
----------------------------------------------------------------------------------------------------------------
3.16 x 10\10\ 3.16 x 10\8\ 458.3 294.7 80.3 829.7
----------------------------------------------------------------------------------------------------------------
10\11\ 10\9\ 138.5 84.9 19.1 243.8
----------------------------------------------------------------------------------------------------------------
3.16 x 10\11\ 3.16 10\9\ 32.1 19.5 4.2 58.5
----------------------------------------------------------------------------------------------------------------
10\12\ 10\10\ 0.0 0.0 0.0 0.0
----------------------------------------------------------------------------------------------------------------
Total 1159 702 216 2078
----------------------------------------------------------------------------------------------------------------
Appendix 2.--Modeled Percentage Distribution of Food Servings
Contaminated with L. monocytogenes at Time of Consumption for Foods
That Do Not Support Growth
Table III-16 in the FDA/FSIS LmRA (see Section III, p. 73) reports
the modeled distribution of L. monocytogenes at time of consumption in
``dose bins'' that combine the distribution of L. monocytogenes for
several doses. For example, in Table III-16 the column labeled 1-1,000
cfu/serving includes the combined modeled distributions for doses of 1,
3, 10, 32, 100, 316, and 1,000 cfu/serving. To provide additional
information about the distribution at time of consumption of L.
monocytogenes in servings of foods that generally do not support its
growth, in Table 6 we break the modeled distributions from Table III-16
into more discrete dose bins within the range of 1 cfu/serving to
1,000,000 cfu/serving. In addition, in Table 6 we include a
contamination level, in cfu/g, that would be associated with each given
dose if there was a uniform serving size of 100 g.
[[Page 7310]]
Table 6.--Modeled Percentage Distribution of Food Servings Contaminated with L. monocytogenes at Time of
Consumption for Foods That Do Not Support Growth
----------------------------------------------------------------------------------------------------------------
Median Percentage of Food Servings Contaminated with L. monocytogenes at:
--------------------------------------------------------------------------------------------------
> 10 - 100 > 10\3\ - > 10\4\ - > 10\5\ -
Food Category 1 cfu/ > 1 - 10 cfu/ cfu/ 100 to 10\3\ 10\4\ cfu/ 10\5\ cfu/ 10\6\ cfu/
serving serving\b\ (> serving\c\ (> cfu/ serving\e\ serving\f\ serving\g\
(0.01 cfu/ 0.01-0.1 cfu/ 0.1 - 1 cfu/ serving\d\ (> (> 10 - 100 (> 100 - (> 10\3\ -
g\a\) g) g) 1 - 10 cfu/g) cfu/g) 1,000 cfu/g) 10\4\ cfu/g)
----------------------------------------------------------------------------------------------------------------
Seafood
----------------------------------------------------------------------------------------------------------------
Preserved 0.9 (< 0.1, 2.1 (0.1, 1.2 (< 0.1, 0.6 (< 0.1, 0.2 (< 0.1, 0.1 (< 0.1, 0.1 (< 0.1,
Fish 3.1)\h\ 8.0) 5.8) 4.0) 2.3) 1.2) < 0.7)
----------------------------------------------------------------------------------------------------------------
Dairy
----------------------------------------------------------------------------------------------------------------
Hard Cheese < 0.1 < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1,
(< 0.1, 0.6) 0.4) 0.2) 0.1) < 0.1) < 0.1)
.5)
----------------------------------------------------------------------------------------------------------------
Processed 0.2 (< 0.1, 0.3 (< 0.1, 0.1 (< 0.1, 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1,
Cheese 0.6) 0.9) 0.4) 0.2) 0.1) 0.1) < 0.1)
----------------------------------------------------------------------------------------------------------------
Ice Cream/ 0.1 (< 0.1, 0.2 (0.1, 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1,
Frozen 0.2) 0.3) 0.1) < 0.1) < 0.1) < 0.1) < 0.1)
Dairy
----------------------------------------------------------------------------------------------------------------
Cultured 0.1 (< 0.1, 0.2 (< 0.1, 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1,
Milk 1.1) 1.5) 0.8) 0.4) 0.2) 0.1) < 0.1)
Products
----------------------------------------------------------------------------------------------------------------
Deli-type 1.9 (0.7, 3.0 (0.9, 1.1 (0.3, 0.3 (0.1, 0.1 (< 0.1, < 0.1 (< 0.1, < 0.1 (< 0.1,
salads 3.7) 5.2) 1.9) 0.7) 0.2) 0.1) < 0.1)
----------------------------------------------------------------------------------------------------------------
\a\ Assumes a uniform serving size of 100 g.
\b\ Includes combined estimates for doses of 3.16 and 10 cfu.
\c\ Includes combined estimates for doses of 31.6 and 100 cfu.
\d\ Includes combined estimates for doses of 316 and 1,000 cfu.
\e\ Includes combined estimates for doses of 3160 and 10,000 cfu.
\f\ Includes combined estimates for doses of 31,600 and 100,000 cfu.
\g\ Includes combined estimates for doses of 316,000 and 1,000,000 cfu.
\h\ Numbers in parentheses denote the 5th and 95th percentile uncertainty levels, respectively.
Dated: January 23, 2008.
Margaret O'K. Glavin,
Associate Commissioner for Regulatory Affairs.
[FR Doc. 08-549 Filed 2-6-08; 8:45 am]
BILLING CODE 4160-01-S