

[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]                         

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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.

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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://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://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://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).
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    \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)'').
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    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).
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    \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.
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    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).
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    \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).
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    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:
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    \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).
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     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\
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    \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.
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    Examples of RTE foods that generally are considered to not support 
the growth of L. monocytogenes include:\6\
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    \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.
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     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\
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    \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.
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    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.
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    \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.
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    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).
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    \9\ A more virulent strain would have the potential to cause 
listeriosis with fewer cells than a less virulent strain.
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    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.
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    \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.
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    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://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://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://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://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://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://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://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://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://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://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://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
