Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64107

compliance would be highly speculative

and essentially be a requirement that

FDA perform a worst-case analysis

when evaluating the potential

environmental impact of an agency

action. This is simply not what NEPA

requires (see Robertson v. Methow

Valley Citizens Council, 490 U.S. 332,

355 (1989)).

Importantly, the poultry final rule, in

and of itself, does not permit any

additional building or operation of

irradiation facilities, and thus, does not

directly result in any increased risk of

accidents at such facilities. Before an

irradiation facility is built, other

regulatory agencies with oversight

regarding its site design, location,

licensing, and radiation control

procedures (such as the NRC) must

issue permits. The evaluation of the

environmental impact of the

construction and operation of these

facilities is, under NEPA, the

responsibility of the licensing agency or

agencies. FDA’s environmental

evaluation in this case, and thereby

FDA’s FONSI, was not intended to

reassess the environmental impact

issues that are the responsibility of other

regulatory agencies. In fact, under

NEPA, an agency is not required to

assess the environmental impact of a

portion of a project where a second

agency has jurisdiction over such

portion (see State of N.C. v. City of

Virginia Beach, 951 F.2d 596 (4th Cir.

1991)).

Accordingly, even if there have been

accidents at irradiation facilities, or

even if there would be an increased risk

of such accidents as a result of the

poultry final rule, these facts have no

bearing on FDA’s EA of its action. Thus,

FDA is denying a hearing on this issue

because a hearing will not be granted on

factual issues that are not determinative

with respect to the action requested

(§ 12.24(b)(4)).

d. Alleged contradiction. FWI also

objects to FDA’s FONSI on the grounds

of an alleged contradiction between

information in FSIS’s EA and other FSIS

documents and cites an article from The

Food and Drug Letter (April 28, 1989) in

support of its objection. According to

FWI, FSIS declared in its EA that

alternatives to irradiation need not be

discussed when considering the

environmental impact of the technology

and yet, in the article in The Food and

Drug Letter, did not mention irradiation

as one of the research areas for

potentially solving the bacterial

problem.

The material cited by FWI does not

support its contention. In preparing an

EA, petitioners are required, under

§ 25.31a(a)(11), to consider alternatives

to the proposed action if potential

adverse environmental impacts have

been identified for the proposed action

(§ 25.31a(a)(11)). After evaluating the

FSIS’ EA, the agency found that

irradiation of poultry in compliance

with existing laws and regulations will

not lead to a significant impact on the

environment. Because no adverse

impacts are expected, the agency did

not require, and FSIS did not address,

alternatives to the proposed action

under format item 11 of the EA. It

should also be noted that, contrary to

FWI’s contention, FSIS did not claim in

its EA that irradiation is the only

solution to food-borne pathogens.

The article referred to by FWI from

The Food and Drug Letter discusses

areas identified by FSIS for future

research for potential solutions to the

problem of microbial contamination in

poultry; at that time, irradiation had

already been a subject of research as a

potential solution to this problem. Thus,

there is no contradiction between the

statements made by FSIS in its EA and

in the article in The Food and Drug

Letter.

In order to justify a hearing on this

issue, FWI would need to provide

credible evidence that challenges FDA’s

conclusion that the irradiation of

poultry in compliance with existing

regulations will not lead to a significant

impact on the environment (see

§ 12.24(b)(2)). FWI has not done so and,

thus, has failed to meet a threshold

burden of tendering evidence that

suggests a need for a hearing (Costle v.

Pacific Legal Foundation, supra, 445

U.S. at 214).

V. Summary and Conclusions

The safety of poultry irradiated at up

to 3 kGy has been thoroughly tested and

the data have been reviewed by the

agency. As discussed previously, FDA

concluded that the available studies

establish the safety of poultry irradiated

at doses up to 3 kGy for human

consumption.

The petitioner has the burden to

demonstrate safety before FDA can

approve the use of a food additive.

Nevertheless, once the agency makes a

finding of safety in an approval

document, the burden shifts to an

objector, who must come forward with

evidence that calls into question FDA’s

conclusion (American Cyanamid Co. v.

FDA, 606 F2d. 1307, 1314–1315 (D.C.

Cir. 1979)).

None of those objecting to the final

rule has identified any information in

the record that was misconstrued by

FDA to support the objector’s claim that

the agency incorrectly concluded that

consumption of poultry irradiated at up

to 3 kGy is safe. Nor has any objector

established that the agency overlooked

significant information in reaching its

conclusion. Indeed, none of the

objections presented any relevant

evidence that has not already been

carefully reviewed and weighed by the

agency. The agency has determined that

the objections do not raise any genuine

and substantial issue of fact that would

justify an evidentiary hearing on any of

the objections raised (§ 12.24(b)).

Accordingly, FDA is overruling the

objections and is denying the requests

for a hearing. In addition, FWI’s request

for a stay of the effectiveness of the May

2, 1990, regulation until a hearing is

held is moot because FDA is denying all

hearing requests.

FDA is confirming May 2, 1990, as the

effective date of the regulation.

VI. Reference

The following reference has been

placed on display in the Dockets

Management Branch (HFA–305), Food

and Drug Administration, 12420

Parklawn Dr., rm. 1–23, Rockville, MD

20857, and may be seen by interested

persons between 9 a.m. and 4 p.m.,

Monday through Friday.

1. FDA, Bureau of Foods, ‘‘Toxicological

Principles for the Safety Assessment of Direct

Food Additives and Color Additives Used in

Food,’’ Appendix III, p. 18, 1982.

Dated: November 26, 1997.

Michael A. Friedman

Lead Deputy Commissiner for the Food and

Drug Administration.

[FR Doc. 97–31739 Filed 12–2–97; 8:45 am]

BILLING CODE 4160–01–F

DEPARTMENT OF HEALTH AND

HUMAN SERVICES

Food and Drug Administration

21 CFR Part 179

[Docket No. 94F–0289]

Irradiation in the Production,

Processing and Handling of Food

AGENCY: Food and Drug Administration,

HHS.

ACTION: Final rule.

SUMMARY: The Food and Drug

Administration (FDA) is amending the

food additive regulations to provide for

the safe use of a source of radiation to

treat refrigerated or frozen uncooked

meat, meat byproducts, and certain meat

food products to control foodborne

pathogens and extend product shelf-life.

This action is in response to a petition

filed by Isomedix, Inc.
64108 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

1E. coli O157:H7 causes hemorrhagic colitis, a

severe illness, the symptoms of which include high

fever, vomiting, and bloody diarrhea, with

consequent dehydration. In patients with weakened

or immature immune systems, the infection can

progress to hemolytic uremic syndrome (HUS), a

life-threatening kidney disease with a mortality rate

of 6 percent (Ref. 3). The number of outbreaks in

the United States reported to be associated with E.

coli O157:H7 has increased from 4 in 1992 to 30

in 1994; E. coli O157:H7 has been estimated to

cause more than 20,000 infections and 250 deaths

each year (Ref. 4).

Salmonella sp. are a leading reported cause of

foodborne bacterial diseases (Ref. 5) and have been

reported to be associated with 48 percent of beefrelated outbreaks (Ref. 2). C. perfringens is also an

important agent of foodborne microbial disease,

with a projected incidence of 652,000 cases and 7.6

deaths per year. During 1973 to 1987, beef

accounted for 30 percent of all C. perfringens type

A food poisoning outbreaks (Ref. 6).

2 Meat. (1) The part of the muscle of any cattle,

sheep, swine, or goats, which is skeletal or which

is found in the tongue, or in the diaphragm, or in

the heart, or in the esophagus, with or without the

accompanying and overlying fat, and the portions

of bone, skin, sinew, nerve, and blood vessels

which normally accompany the muscle tissue and

which are not separated from it in the process of

dressing. It does not include the muscle found in

the lips, snout, or ears. This term, as applied to

products of equines, shall have a meaning

comparable to that provided in this paragraph with

respect to cattle, sheep, swine, and goats.

(2) The product derived from the mechanical

separation of the skeletal muscle tissue from the

bones of livestock using the advances in mechanical

meat/bone separation machinery and meat recovery

systems that do not crush, grind, or pulverize

bones, and from which the bones emerge

comparable to those resulting from hand-deboning

(i.e., essentially intact and in natural physical

conformation such that they are recognizable, such

as loin and rib bones, when they emerge from the

machinery) which meets the criteria of no more

than 0.15 percent or 150 mg/100 gm of product for

calcium (as a measure of bone solids content)

within a tolerance of 0.03 percent or 30 mg.

3 Meat byproduct. Any part capable of use as

human food, other than meat, which has been

derived from one or more cattle, sheep, swine, or

goats. This term, as applied to products of equines,

shall have a meaning comparable to that provided

in this paragraph with respect to cattle, sheep,

swine, and goats.

4Specifically, those meat food products within

the meaning of 9 CFR 301.2(uu), with or without

nonfluid seasoning, that are otherwise composed

solely of intact or ground meat and/or meat

byproducts (e.g., ground beef as in 9 CFR 319.15(a);

hamburger as in 9 CFR 319.15(b); certain defatted

beef or pork products as in 9 CFR 319.15(e) and 9

CFR 319.29(a), respectively; mechanically separated

(species) as in 9 CFR 319.5).

DATES: Effective December 3, 1997;

written objections and requests for a

hearing by January 2, 1998.

ADDRESSES: Submit written objections to

the Dockets Management Branch (HFA–

305), Food and Drug Administration,

12420 Parklawn Dr., rm. 1–23,

Rockville, MD 20857.

FOR FURTHER INFORMATION CONTACT:

Patricia A. Hansen, Center for Food

Safety and Applied Nutrition (HFS–

206), Food and Drug Administration,

200 C St. SW., Washington, DC 20204,

202–418–3093.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction

II. Evaluation of Safety

III. Evaluation of the Safety of the

Petitioned Use of a Source of Radiation

A. General Framework

B. Radiation Chemistry

C. Toxicological Considerations

D. Nutritional Considerations

E. Microbiological Considerations

IV. Current Good Manufacturing

Practice Considerations

V. Labeling

VI. Conclusion of Safety

VII. Environmental Impact

VIII. Objections

IX. References

I. Introduction

In a notice published in the Federal

Register of August 25, 1994 (59 FR

43848), FDA announced that a food

additive petition (FAP 4M4428) had

been filed by Isomedix, Inc., 11 Apollo

Dr., Whippany, NJ 07891, proposing

that part 179 Irradiation in the

Production, Processing and Handling of

Food (21 CFR part 179) be amended to

provide for the safe use of a source of

radiation to treat the fresh or frozen raw

edible tissue of domesticated

mammalian human food sources for

purposes of reduction of parasites and

microbial pathogens, and extension of

product shelf-life.

Several letters, from members of

academia and from a trade group, were

received in response to the filing of the

petition. The letters urged FDA to

approve irradiation of beef and other

meats, and expressed the belief that the

use of irradiation could benefit public

health and improve the safety of meat

by controlling foodborne pathogens.

Because the letters expressed general

support for the agency’s action, but

provided no substantive information,

these comments will not be addressed

further.

The comments illustrate, however, a

heightened public awareness of the

health threat posed by pathogens in or

on meat. Among these, Escherichia coli

O157:H7, Salmonella sp., and

Clostridium perfringens are of primary

concern from a public health

standpoint; E. coli O157:H7 because of

the severity of the illness associated

with the organism, and Salmonella and

C. perfringens because of the high

number of outbreaks and individual

cases of foodborne illness associated

with these pathogens (Refs. 1 and 2).1

Although proper handling practices

and cooking to recommended internal

temperatures are effective interventions

in preventing foodborne illness

associated with meat products, much

effort has gone into the development of

other interventions aimed at reducing

microbial pathogens. Irradiation has

been proposed as one such additional

tool.

The subject petition requests that FDA

amend the food additive regulations to

authorize the use of ionizing radiation

to ‘‘control microbial pathogens in raw,

fresh-chilled, and frozen intact and

comminuted edible tissue of the skeletal

muscle and organ meat of domesticated

mammalian food sources; with

concomitant control of infectious

parasites, and, extension of acceptable

edible/marketable life of chilled/

refrigerated and defrosted meat through

the reduction in levels of spoilage

microorganisms.’’ The petition also

specifies that the proposed foods are to

be ‘‘primarily from bovine, ovine,

porcine, and equine sources.’’ The

petition requests that a maximum dose

of 4.5 kiloGray (kGy) be established for

the irradiation of fresh (chilled, not

frozen) meat, and that a maximum dose

of 7.0 kGy be established for the

irradiation of frozen meat.

In this final rule, FDA is adding

refrigerated and frozen uncooked meat,

meat byproducts (e.g., edible organs

such as the liver and the kidneys) and

certain meat food products (e.g., ground

beef and hamburger) to the list of foods

that are authorized (under § 179.26(b))

for treatment with ionizing radiation. In

addition, FDA is establishing 4.5 kGy as

the maximum permitted dose for

irradiation of refrigerated meat, meat

byproducts, and certain meat food

products; and 7.0 kGy as the maximum

permitted dose for irradiation of frozen

meat, meat byproducts and certain meat

food products.

The foods that are set forth in the

regulation below are all subject to the

Federal Meat Inspection Act (21 U.S.C.

601, et seq.), and are defined by the U.S.

Department of Agriculture/Food Safety

and Inspection Service (USDA/FSIS) in

title 9 of the Code of Federal

Regulations. These foods include meat,

as defined by USDA/FSIS in 9 CFR

301.2(rr),2 meat byproducts, as defined

by USDA/FSIS in 9 CFR 301.2(tt),3 and

certain meat food products4 from among

those defined by USDA/FSIS in 9 CFR

301.2(uu).

In the text of this document, the term

‘‘meat’’ will be used to refer collectively

to meat, meat byproducts, and

applicable meat food products. When,

in the text of this document, the

discussion is also applicable to foods

that might, in common usage, be

referred to as a meat or as a type of meat

(e.g., chicken, turkey, or fish), but that
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64109

5The term ‘‘radiation chemistry’’ refers to the

chemical reactions that occur as a result of the

absorption of ionizing radiation. Like all chemical

reactions, these radiation-induced reactions depend

on the nature of the reactants and on the energy

supplied to the system. In the context of food

irradiation, the radiation-induced reactions depend

on the chemical constituents of the food and such

factors as the ambient atmosphere (which also

contains potential reactants), the physical state of

the food, the ambient temperature, and the

radiation dose. Radiation-induced chemical

reactions can affect the detailed chemical

composition of the food and the cellular

components of the microorganisms in or on the

food.

do not conform to the definitions of

meat, meat byproducts, or meat food

products in title 9 of the Code of

Regulations, the term ‘‘flesh food(s)’’

will be used instead.

II. Evaluation of Safety

Under section 201(s) of the Federal

Food, Drug, and Cosmetic Act (the act)

(21 U.S.C. 321(s)), a source of radiation

used to treat food is defined as a food

additive:

* * * The term ‘‘food additive’’ means any

substance the intended use of which results

or may reasonably be expected to result,

directly or indirectly, in its becoming a

component or otherwise affecting the

characteristics of any food (including any

substance intended for use in producing,

manufacturing, packing, processing,

preparing, treating, packaging, transporting,

or holding food; and including any source of

radiation intended for any such use) * * *.

Under section 409(c)(3)(A) of the act

(21 U.S.C. 348(c)(3)(A)), a food additive

cannot be approved for a particular use

unless a fair evaluation of the evidence

establishes that the additive is safe for

that use. The concept of safety

embodied in the Food Additives

Amendment of 1958 (the Amendment)

is explained in the legislative history of

the provision: ‘‘Safety requires proof of

a reasonable certainty that no harm will

result from the proposed use of the

additive. It does not—and cannot—

require proof beyond any possible doubt

that no harm will result under any

conceivable circumstance’’ (H. Rept.

2284, 85th Cong., 2d sess. 4 (1958)).

This concept of safety has been

incorporated into FDA’s food additive

regulations (21 CFR 170.3(i)).

The legislative history of the

Amendment clearly reflects that

Congress recognized that it is

impossible to establish with complete

certainty the absolute harmlessness of

any chemical substance. The concept of

safety contained in the Amendment has,

as its focus, the reduction of uncertainty

about the safety of an additive to the

point where the agency can reasonably

conclude that no harm will result from

its proposed use.

The statute does not prescribe the

safety tests to be performed but leaves

that determination to the discretion and

scientific expertise of FDA. Not all food

additives require the same amount or

type of testing. The amount and type of

testing required to establish the safety of

an additive will vary depending on the

particular additive and its intended use.

In this particular case, the additive is

not, literally, added to food. Instead, a

source of radiation is used to process or

treat food such that, analogous to other

food processes, its use can affect the

characteristics of the food. In the subject

petition, the intended technical effect is

a change in the microbial load of the

food, specifically, a reduction in the

numbers of microorganisms, both

pathogenic and nonpathogenic, in or on

meat. It is important to realize, however,

that the petitioner is not required to

show, nor is FDA permitted to consider,

that irradiation of meat has benefits,

health or otherwise, for consumers of

irradiated meat. The legislative history

of the Amendment is clear on this point:

The question of whether an additive

produces such [a technical] effect (or how

much of an additive is required for such an

effect) is a factual one, and does not involve

any judgement on the part of the Secretary

whether such effect results in any added

‘value’ to the consumer of such food or

enhances the marketability from a

merchandising point of view.

S. Rept. 2422, 85th Cong., 2d sess. 7

(1958). Accord: H. Rept. 2284, 85th

Cong., 2d sess. 6 (1958)

Thus, in evaluating the safety of a

source of radiation to treat meat

intended for human consumption, FDA

cannot consider the possible benefits to

consumers or to food processors.

Instead, the agency must identify the

various effects that can result from

irradiating this food and assess whether

any of these effects may pose a human

health risk. In this regard, three areas of

concern need to be addressed: potential

toxicity, nutritional adequacy, and

potential microbiological risk. Each of

these areas is discussed in detail in

section III of this document.

III. Evaluation of Safety of the

Petitioned Use of a Source of Radiation

The petitioner submitted a large

number of published articles and other

study reports containing data and

information in the areas of radiation

chemistry,5 dietary consumption

patterns, toxicology, nutrition, and

microbiology. FDA has reviewed the

data and studies submitted in the

petition, as well as other information in

its files relevant to the safety and

nutritional adequacy of meat treated

with ionizing radiation. Specifically, the

agency evaluated information

concerning:

1. Studies of the radiation chemistry

of food components and whole foods,

including chemical analyses of

irradiated flesh foods.

2. Toxicity studies of flesh foods,

including studies of irradiated beef,

pork, horse meat, chicken, and fish.

3. Studies of nutrient levels in, and

information regarding dietary

consumption patterns of, irradiated

flesh foods.

4. Studies of the effects of irradiation

on both pathogenic and nonpathogenic

microorganisms.

A. General Framework

To determine whether the use of a

food additive is safe, FDA typically

considers the chemical identity and

amount of the additive that will be

ingested in light of what is known

regarding its toxicity. In the case of

substances added directly to food, the

agency estimates the amount of the

additive that will be ingested from the

proposed use levels of the additive in

particular foods or food types along

with consideration of consumption

patterns of those foods. Information

about the chemical structure of an

additive and an assessment of the likely

consumption levels of the additive,

together with information obtained from

toxicological testing, forms the basis for

evaluating safety.

In the case of food irradiation, the

effects of this form of processing on the

characteristics of the treated foods are a

direct result of the chemical reactions

induced by the absorbed radiation.

Research has established that the types

and amounts of products generated by

radiation-induced chemical reactions

(hereinafter referred to as ‘‘radiolytic

products’’) depend on the chemical

constituents of the food and on the

conditions of irradiation. Information

regarding the chemical structures and

the amounts of radiolytic products in

particular food types, together with the

information obtained from toxicological

testing, forms a sound basis for

evaluating the toxicological safety of an

irradiated food.

In the case of food irradiation, the

nutritional adequacy and the

microbiological safety of the treated

foods must also be evaluated. Research

has shown that the principles of

radiation chemistry govern the extent of

changes both in the nutrient levels and

in the microbial load of irradiated foods.

Key factors include the specific nutrient

or microorganism of interest, the food,

and the conditions of irradiation.
64110 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

6Several books provide more detailed discussions

of radiation chemistry with references to the large

number of original research studies, particularly in

the area of food irradiation. Sources that can be

consulted for further information include, but are

not limited to: Radiation Chemistry of Major Food

Components, edited by P. S. Elias and A. J. Cohen,

Elsevier, Amsterdam, 1977; Recent Advances in

Food Irradiation, edited by P. S. Elias and A. J.

Cohen, Elsevier, Amsterdam, 1983; and Diehl, J. F.,

‘‘Chemical Effects of Ionizing Radiation,’’ Ch. 3 in

Safety of Irradiated Foods, Marcel Dekker, New

York, 1995.

7Proteins are composed of amino acids joined by

peptide bonds. The characteristic sequence of

amino acids in a particular protein is known as the

primary structure. The extent and nature of the

coiling or pleating of different segments of the

protein is known as the secondary structure. The

three dimensional shape of the coiled or pleated

protein is known as the tertiary structure.

Denaturation refers to structural changes that result

in a loss of biological properties; these are usually

changes in the secondary or tertiary structures.

8The fat in meat is composed primarily of

triglycerides, each molecule of which contains three

fatty acids. The predominant fatty acids in the

triglycerides of flesh foods are oleic, palmitic,

linoleic, and stearic acid.

9One major effort to determine whether radiolytic

products in a flesh food presented any risk to

human health is described in a report entitled

‘‘Evaluation of the Health Aspects of Certain

Compounds Found in Irradiated Beef,’’ prepared by

the Life Sciences Research Office of the Federation

B. Radiation Chemistry

Scientists have compiled an

enormous body of data regarding the

effects of ionizing radiation on different

foods under various conditions of

irradiation. Because of the complexity

in the composition of any food and the

large numbers of specific radiationinduced reactions that can occur, the

agency will limit its discussion here to

the broad principles that are applicable

to this decision.6 These broad principles

provide the basis for extrapolation and

generalization from data obtained in

specific foods irradiated under specific

conditions to draw conclusions

regarding foods of a similar type

irradiated under different, yet related,

conditions.

1. Factors Affecting the Radiation

Chemistry of Foods

Apart from the chemical composition

of the food itself, the factors, or

irradiation conditions, that are most

important in considering the radiation

chemistry of a given food include the

radiation dose, the physical state of the

food (e.g., the solid or frozen versus the

liquid or nonfrozen state), and the

ambient atmosphere (air, reduced

oxygen, vacuum, etc.).

With respect to dose, the amounts of

radiolytic products generated in a

particular food have been shown to be

directly proportional to the radiation

dose (Refs. 7, 8, and 9). Thus, it is

entirely sound to extrapolate from data

obtained at high radiation doses to draw

conclusions regarding the amounts of

radiolytic products expected to be

generated at lower doses.

The radiation chemistry of food is

also strongly influenced by the physical

state of the food. If all other conditions,

including dose and ambient

atmosphere, are the same, the extent of

chemical change that occurs in a

particular food in the frozen state is less

than the change that occurs in the same

food in the nonfrozen state. This is a

result of the reduced mobility, in the

frozen state, of the initial products of

irradiation (free radicals, which are

highly energetic, unstable molecules).

Because of their reduced mobility, these

free radicals tend to recombine to form

the original substance rather than to

diffuse through the food to react with

other components of the food matrix

and thereby form different substances

(Refs. 9 and 10). Thus, both the types

and the amounts of radiolytic products

are affected by the physical state of the

food, and, for a given food, higher

radiation doses are needed to effect the

same degree of chemical change in

frozen versus nonfrozen food. Higher

radiation doses are also needed to

accomplish the same antimicrobial

technical effect in a frozen food versus

a nonfrozen food of the same type.

The formation of radiolytic products

in a given food is also affected by the

ambient atmosphere. Irradiation in an

atmosphere of high oxygen content

generally produces both a greater

variety, and greater amounts, of

radiolytic products in the food than

would be produced in an atmosphere of

lower oxygen content. This is because

irradiation initiates certain oxidation

reactions, reactions that occur with

greater frequency in foods with high fat

content (Refs. 11 and 12). The final

products of radiation-induced oxidation

reactions in foods are similar to those

produced by oxidation reactions

induced by other processes (e.g., storage

or heating in air).

In general, the types of products

generated by irradiation are similar to

those produced by other food processing

methods. Radiation-induced chemical

changes, if sufficiently large, however,

may cause changes in the organoleptic

properties of the food. Because food

processors wish to avoid undesirable

effects on taste, odor, color, or texture,

there is an incentive to minimize the

extent of these chemical changes in the

food. Thus, irradiation is often

conducted under reduced oxygen levels

or on food in the frozen state.

2. Radiation Chemistry of the Major

Components of Flesh Foods

The major components of all foods are

water, carbohydrates, proteins, and

lipids. Flesh foods, as a group, have

very little carbohydrate content, and are

comprised primarily of water, proteins,

and lipids. The radiation chemistry of

these components is well established.

In foods of relatively high water

content, such as flesh foods, free

radicals produced by radiolysis of water

form the majority of the initial products

of the radiation-induced chemical

reactions. These free radicals, in turn,

react with the other components of the

food to form the final, stable, radiolytic

products.

With respect to proteins, several types

of reactions can occur as a result of

irradiation. One type of reaction is the

breaking of a small number of peptide

bonds to form polypeptides of shorter

length than the original protein (Refs. 13

and 14).7 Radiation-induced aggregation

or cross-linking of individual

polypeptide chains can also occur; these

processes result in protein denaturation

(Refs. 13 through 16). In irradiated flesh

foods, most of the radiolytic products

derived from proteins have the same

chemical composition but are altered in

their secondary and tertiary structures.

These changes are similar to those that

occur as a result of heating, but in the

case of irradiation, such changes are far

less pronounced and the amounts of

reaction products generated are far

lower.

A third type of reaction that can occur

when proteins are irradiated involves

the reaction of amino acids in the

polypeptide chain with the free radicals

produced from water, without the

breaking of peptide bonds (Refs. 17 and

18). The compounds produced by such

reactions, like the other radiolytic

products derived from proteins, are

similar or identical to those found in

foods that have not been irradiated. The

radiolytic products resulting from this

third type of reaction occur in very

small amounts; various studies have

established that there is little change in

the amino acid composition of flesh

foods irradiated at doses below 50 kGy

(Refs. 19 and 20), a dose approximately

seven times greater than the highest

dose set forth in the regulation below.

The radiation chemistry of lipids

(fats) is also well established.8

Numerous studies have been performed

with various oils and fats and also on

the lipid fraction of irradiated foods

(see, e.g., Refs. 21 through 25). A variety

of radiolytic products derived from

lipids have been identified, including

fatty acids, esters, aldehydes, ketones,

alkanes, alkenes, and other

hydrocarbons (Refs. 7, 22, 23, 25, and

26a through 26c).9 All of these types of
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64111

of American Societies for Experimental Biology

under contract with the U.S. Army (‘‘the FASEB/

LSRO report’’ and supplements, Refs. 26a through

26c).

This report presented the results of chemical

analyses performed on frozen beef irradiated under

vacuum at a dose of 56 kGy. Sixty-five volatile

radiolytic products were identified, most of which

originated from the lipid fraction. This study

established that these 65 radiolytic products were

either identical or structurally similar to substances

found in foods that have not been irradiated, and

that these individual radiolytic products were

produced in very small amounts (generally 1 to 700

parts per billion of irradiated beef), even at a

radiation dose eight times higher than the highest

dose requested in the petition.

10The proximate composition of flesh foods does

not vary widely. Beef and lamb, for example, are

composed of approximately 17 to 20 percent

protein, 15 to 25 percent fat, and 56 to 65 percent

water, depending on the cut. Chicken, depending

on the cut and whether the skin is included, is

approximately 18 to 25 percent protein, 5 to 19

percent fat, and 57 to 75 percent water. Fish,

depending on the species, is approximately 16 to

27 percent protein, 1 to 20 percent fat, and 60 to

75 percent water.

The predominant fatty acids in the triglycerides

of flesh foods are oleic, palmitic, linoleic, and

stearic acid. The saturated fatty acids (palmitic and

stearic acid) contribute approximately 8 to 12

percent of the fat content in both beef and lamb.

The fat in chicken (skin on) and pork is composed

of approximately 2 to 9 percent saturated fatty

acids. The amino acid content of flesh foods also

does not vary widely. In beef, pork, lamb, and

chicken, tryptophan contributes the smallest weight

percentage and lysine the greatest weight

percentage to the amino acid content (see Refs. 28

and 29).

compounds are also found in foods that

have not been irradiated. These types of

compounds are also produced by

heating foods, and, in the case of

heating, are produced in amounts far

higher than the trace amounts that result

from irradiating foods (Refs. 23 and 27).

In summary, the results obtained from

chemical analyses of irradiated flesh

foods establish that there would be very

small amounts of individual radiolytic

products generated by radiation doses

comparable to those proposed in the

petition. In addition, most of these

radiolytic products are either the same

as, or structurally very similar to,

compounds found in foods that have not

been irradiated. Because of their

structural similarities to compounds

found in foods that have not been

irradiated, these radiolytic products

would be expected to be toxicologically

similar to such compounds as well.

Thus, the available information

regarding the radiation chemistry of the

major components of flesh foods

supports the proposition that there is no

reason to suspect a toxicological hazard

due to consumption of an irradiated

flesh food.

3. Flesh Foods as a Generic Class

As noted above, flesh foods are

comprised primarily of water, proteins,

and lipids.10 While the proportions of

the individual amino acids in the

proteins and the individual fatty acids

in the lipid fraction vary somewhat

among the different flesh foods, the

same chemical components provide the

basis for any chemical reactions in flesh

foods caused by the absorption of

ionizing radiation. Because of this, the

same compounds (in slightly varying

proportions) will constitute the majority

of radiolytic products in all irradiated

flesh foods.

The large number of studies on the

radiation chemistry of food and food

components, taken together, support

this conclusion regarding commonality

in the chemistry and predictability of

the types and amounts of radiolytic

products (see, e.g., Refs. 14, 18, and 30).

Accordingly, it is scientifically sound to

generalize from the data obtained in

studies of a variety of specific irradiated

flesh foods to draw conclusions

regarding the irradiation of flesh foods

as a class (Ref. 30). Because of the

foregoing, FDA has determined that, to

evaluate the safety of foods that are the

subject of this petition (i.e., meat and

meat byproducts as defined in 9 CFR

301.2(rr) and (tt), and certain meat food

products from among those defined in 9

CFR 301.2(uu)), it is entirely appropriate

to consider the available data from all

flesh foods, irradiated under a variety of

conditions. Details of the agency’s

analysis are presented below.

C. Toxicological Considerations

As discussed previously, all of the

available information from the results of

chemical analyses suggests that there is

no reason to suspect a toxicological

hazard due to consumption of an

irradiated food. However, while

chemical analyses have not identified

the presence of any particular radiolytic

products in amounts that would raise a

toxicological concern, the agency notes

that the large body of data from studies

where irradiated flesh foods were fed to

laboratory animals provides an

independent way to assess toxicological

safety. Thus, the agency has also

examined all the available data from

toxicological studies that are relevant to

the safety of irradiated meat, namely, all

of those with flesh foods.

This includes the data relied on by

the agency in its previous evaluation of

the safety of poultry irradiated at doses

up to 3 kGy (discussed in the Federal

Register of May 2, 1990 (55 FR 18538)),

as well as additional data in FDA files

from studies of irradiated meat, poultry,

and fish. The agency’s analysis

incorporates the principle that

toxicological data collected from studies

on foods irradiated at high doses can be

applied to the toxicological evaluation

of foods of the same generic class

receiving lower doses (Refs. 14 and 30).

The agency’s analysis also takes into

account the known effects of other

conditions of irradiation, such as the

physical state of the food and the

ambient atmosphere, to compare the

results of different studies. A summary

of that analysis is presented below.

1. Toxicity Studies of Flesh Foods

Relied Upon by FDA in Previous Safety

Evaluations

In the early 1980’s, as part of a

regulatory initiative on irradiation of

minor dry ingredients (e.g., spices and

seasonings) and foods irradiated at low

doses, the agency conducted a review of

all toxicological studies of irradiated

foods that were available at that time. In

order to come to timely closure on that

rulemaking, the agency limited its

analysis to whether individual studies

could stand alone to support a safety

decision and to whether the studies

showed any evidence of toxicity

attributable to irradiation. The agency

found no evidence of toxicity that could

be attributed to irradiation of food and

amended its regulations to authorize the

use of irradiation on foods at low doses

(no greater than 1 kGy) and on minor

dry ingredients at doses no greater than

30 kGy (51 FR 13376 at 13378, April 18,

1986).

However, FDA concluded that it

could not, at that time, expand approval

to higher doses for foods other than

minor dry ingredients because most of

the individual studies had limitations in

design or conduct. The agency did not

attempt to determine whether the

available toxicological studies, taken as

a whole, could complement each other

and thus compensate for weaknesses in

any individual study or whether

additional information could be

obtained to supplement the available

reports. In addition, FDA had not, at

that time, assessed the nutritional and

microbiological ramifications of

irradiating major dietary components at

doses above 1 kGy.

Although, as noted, many of the

animal feeding studies were not fully

adequate by modern toxicology

standards, the agency found that several

studies were fully adequate in design

and conduct and could stand alone in

support of safety. One of these studies

examined the effects of feeding an

irradiated flesh food to animals;

specifically, rats were fed beef stew or

evaporated milk, each food irradiated at

27.9 and 55.8 kGy (51 FR 13376 at
64112 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

11Although the agency cited this as one study, it

would be more accurately described as one report

where the results of two chronic feeding studies of

irradiated beef stew, one in rats and one in dogs,

and two chronic studies of irradiated evaporated

milk, also one in rats and one in dogs, were

described. The two studies in rats were fully

accepted by the agency. The two studies in dogs

were not fully accepted in the agency’s early review

solely because of the small number of animals used.

12The earlier review had not fully accepted some

of these studies because the reports did not contain

a complete discussion of all relevant details. In

addition, FDA had not fully addressed the possible

significance of the use of an antioxidant to prevent

rancidity from developing during drying of the meat

for storage. The agency subsequently concluded

that the studies were acceptable after receiving

additional information from the laboratory, and

after determining that the antioxidant could not

have changed the effects due to irradiation because

it was added after the chicken was irradiated (see

55 FR 18538 at 18539 and 18540).

13Following publication of the final rule, FDA

received several letters and two submissions within

the 30-day objection period. The submissions

sought revocation of the final rule and requested a

hearing. Elsewhere in this issue of the Federal

Register, FDA is denying the objections and

requests for a hearing because they do not raise

issues of material fact that justify a hearing or

otherwise provide a basis for revoking the final rule.

14The agency evaluated several other studies in

which animals were fed radiation-sterilized chicken

and one in which mice were fed chicken irradiated

at 7 kGy. No treatment-related adverse effects were

seen in any of these studies (55 FR 18538 at 18540).

However, because, in the studies of radiationsterilized chicken, the conditions of irradiation

were different from what would be used in

commerce under the regulation sought by the

petitioner, and because of deficiencies in the data

from the study of chicken irradiated at 7 kGy, FDA

did not rely explicitly on these studies.

15FAO is the Food and Agriculture Organization

of the United Nations, IAEA is the International

Atomic Energy Agency, and WHO is the World

Health Organization.

16For example, the number of animals used in

many of the early studies is smaller than that

commonly used today. Complete histopathology

was not always done or reported. For some studies,

the data are available only in brief summary form.

17 If the radiolytic products in flesh foods

irradiated under test conditions were of any

toxicological significance, consistent effects,

particularly in those tests where the foods were

irradiated at comparable doses and under

comparable conditions, should have been observed.

It is also important to note that at the time many

of these studies were conducted, scientists did not

fully understand the nutritional ramifications of

modifying an animal’s diet by feeding it large

amounts of foods not normally consumed by

laboratory animals. The few adverse effects

observed in certain of the studies are consistent

with what one could expect based on the

nutritional composition of the test diet (Refs. 33 and

35).

13384).11 The data showed that no

treatment-related adverse effects were

observed with either irradiated food.

Subsequent to the agency’s review of

all animal feeding studies, discussed

above, FDA further evaluated a series of

feeding studies of irradiated poultry,

obtaining additional information on

some of the studies and analyzing the

results in greater detail.12 The agency

has previously discussed the findings

of, and its conclusions regarding, these

studies in its decision authorizing the

irradiation of poultry at doses no greater

than 3 kGy (55 FR 18538, May 2,

1990).13 Briefly, the agency concluded

that three animal feeding studies of high

quality (a multigeneration study in rats,

a chronic study in rats, and a 1-year

study in beagle dogs), in which chicken

was irradiated at 3 or 6 kGy and

administered at a level of 35 percent of

the diet, showed no evidence of adverse

toxicological effects attributable to

irradiation (55 FR 18538 at 18539 and

18540). At that time, the agency also

reviewed all other toxicity data on

irradiated poultry and found the results

to be consistent with a conclusion that

irradiated poultry does not present a

toxicological hazard.14

In summary, the agency has

previously found that the following

toxicological studies of irradiated flesh

foods, tested in fully adequate animal

feeding studies, demonstrated no

adverse health effects that could be

attributed to irradiation: beef (as a

component of stew) irradiated at doses

of 27.9 and 55.8 kGy and tested in a

chronic study in rats; chicken irradiated

at doses of 3 kGy and 6 kGy and tested

in a three generation reproduction study

in rats, a chronic study in rats, and a 1-

year study in dogs.

2. Additional Analyses of Toxicity

Data

In 1980, a Joint FAO/IAEA/WHO

Expert Committee15 concluded that

irradiation of any food commodity at an

average dose of up to 10 kGy presents

no toxicological hazard (Ref. 31). Based

in part on the Expert Committee’s

conclusion regarding the absence of

toxicological hazard (as well as

conclusions on the nutritional adequacy

and microbiological safety of irradiated

foods), the Codex Alimentarius

Commission (Codex), in 1984,

recommended that member nations

adopt the Codex finding that the

‘‘wholesomeness of foods irradiated so

as to have absorbed an overall average

dose of up to 10 kGy, is not impaired’’

(Ref. 32). FDA did not adopt the Codex

recommendation in its 1986 rulemaking

because, as noted, it had not yet

analyzed the issues of nutritional

adequacy and microbiological safety in

a sufficiently comprehensive way and

had not pursued the analysis of toxicity

data beyond the examination of

individual studies.

Subsequently, WHO, at the request of

one of its member States, conducted a

new review and analysis of the safety

data on irradiated food (Ref. 33). WHO

considered the extent to which data on

one food type can be extrapolated to

other foods and the extent to which

individual studies of irradiated foods

can be integrated into one large database

to be evaluated as a whole, as opposed

to separate evaluations of a series of

individual studies.

This review included all the studies

in FDA’s files that the agency

considered as reasonably complete, as

well as those studies that appeared to be

acceptable but had deficiencies

interfering with interpretation of the

data (see 51 FR 13376 at 13378). The

WHO review also included data from

USDA and from the Federal Research

Centre for Nutrition at Karlsruhe,

Germany. WHO explicitly documented,

in detail, the data relied on for its

conclusion that the integrated

toxicological database is sufficiently

sensitive to evaluate safety and that no

adverse toxicological effects due to

irradiation were observed in the dose

ranges tested (Ref. 33).

FDA has previously reviewed the

individual studies that are cited in the

WHO report and found no evidence of

toxicity attributable to irradiation. FDA

has now also reexamined these studies

to determine whether the integrated

toxicological database derived from this

body of work, together with the

information regarding radiation-induced

chemical changes, establishes the

toxicological safety of meat irradiated

under the conditions set forth in the

regulation below.

FDA finds that, while many of these

studies cannot individually establish

safety,16 they still provide important

information that, evaluated collectively,

supports a conclusion that there is no

reason to believe that irradiation of flesh

foods presents a toxicological hazard

(Refs. 34a and 34b). The overwhelming

majority of studies reported no adverse

toxicological effects due to consumption

of irradiated flesh foods; equally

important, the few effects observed were

not reproduced in other studies.17 In

addition, FDA notes that many of the

feeding studies were conducted using

flesh foods irradiated at doses far higher

than those proposed in the petition,

providing some exaggeration in terms of

the amounts of radiolytic products

consumed.

Details regarding the important

features of both WHO’s and FDA’s

recent analyses are presented below.

FDA has evaluated all relevant data to

ensure that any potential evidence of

toxicity would not be overlooked.

However, because of the large number of

studies in the total database, this

document focuses on the types of
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64113

18Chronic toxicity studies and reproductive

toxicity studies are generally considered to be the

most sensitive tools for detecting treatment-related

toxicological effects when there is no basis, a priori,

to expect a particular adverse effect. This is because

treatment over the lifetime of the animal in a

chronic study allows the longest time for a subtle

effect to be manifested, and because the developing

organism in reproduction and teratology studies can

be particularly sensitive to toxic effects.

19Although the irradiated fish was not irradiated

at a sterilizing dose or treated to inactivate enzymes

that could lead to decomposition, it was stored

under refrigeration for up to 2 months. Fish fed to

the control group, however, was stored frozen until

incorporated into the diet. Irradiated fish, stored

under refrigeration, had greater opportunity to

undergo decomposition or other spoilage before

consumption. The authors did not report addition

of vitamins or minerals to the diets and did not

report actual nutrient levels in the diet. The authors

also reported a higher incidence of pneumonia and

parasitic infections in the treated group, varying

blood and liver enzyme activities in the different

generations, and a lower albumin/globulin ratio (a

sign of protein deficiency) in the treated group.

studies of irradiated flesh foods that

provide the greatest opportunity for

detecting a treatment-related effect

rather than attempting an exhaustive

discussion of all the available studies.18

In addition, this document concentrates

on those studies that were conducted at

radiation doses greater than, or

comparable to, the doses requested in

the subject petition.

3. Chronic Feeding Studies

Both FDA and WHO evaluated

chronic studies in which various flesh

foods, irradiated at doses ranging from

6 to 74 kGy, were fed to animals (Ref.

36). These include those studies,

discussed previously, on which FDA

has relied in previous safety evaluations

of irradiated foods. The studies in

which no adverse effects were reported

include the following: (1) Studies in

which rats were fed beef irradiated at 56

kGy; pork at 56 kGy; chicken at 6 kGy;

fish at 6 kGy; horse meat at 6.5 kGy; fish

at 56 kGy; beef stew at 56 kGy; a

mixture of beef, pork, fish, and other

foods at 28 kGy; pork brain and egg at

93 kGy; and pork at 74 kGy; (2) studies

in which mice were fed chicken

irradiated at 59 kGy; bacon and bacon

fat at 56 kGy; chicken at 7 kGy; fish and

beef at 56 kGy; pork brain and egg at 93

kGy; and pork and chicken at 56 kGy;

and (3) studies in which dogs were fed

chicken irradiated at 59 kGy; chicken,

beef, and jam at 56 kGy; bacon and

cabbage at 56 kGy, beef at 56 kGy; and

chicken at 6 kGy.

In addition to the studies listed above,

four chronic studies reported

observations that merit further

discussion. FDA has concluded that the

effects reported in these four studies

were either not attributable to

irradiation or were otherwise not of

toxicological significance.

In one study (Ref. 37), weanling rats

fed a mixture of radiation-sterilized (56

kGy) chicken stew and irradiated (6

kGy) cabbage for 19 days were reported

to have reduced levels of alkaline

phosphatase in duodenal tissue.

However, this effect was not seen in

weanling rats fed either (but not both)

radiation-sterilized chicken stew or

irradiated cabbage for 19 days and was

not seen in other rats that were fed the

irradiated chicken stew/cabbage mixture

for 150 days. Additionally, no adverse

histopathological findings that would

indicate a toxic effect were reported.

FDA concludes that the observed

decrease in alkaline phosphatase levels

in weanlings is not of toxicological

significance for three reasons: (1) The

effect observed in weanling rats was not

observed in rats maintained on the same

diet into adulthood, (2) the effect was

not reproduced when either of the two

irradiated foods was fed individually,

and (3) no other reported observations

indicate a toxic effect (Ref. 38).

In a second study (Ref. 39), a diet

composed of a mixture of nine foods,

including bacon, beef, ham, and fish

was radiation-sterilized (56 kGy) and

fed to rats. This study reported a

decreased weight gain for third

generation females, but not for males.

FDA has concluded that this effect

cannot be attributed to irradiation

because it was accompanied by breeding

problems that significantly reduced the

sizes of the groups of rats fed the control

diet as well as the groups of rats fed the

irradiated diet, an observation that is

indicative of overall dietary deficiencies

unrelated to radiation treatment (Ref.

35).

A third study (Ref. 40) reported a

significant increase in heart lesions

(auricular dilatations) in mice fed

radiation-sterilized (56 kGy) pork and

chicken. FDA has determined that this

effect cannot be attributed to the

irradiated flesh foods because a

replicate study with nearly 5,000 mice

of the same strains showed no such

lesions. (Refs. 34a and 38).

Finally, a chronic study in dogs fed

irradiated (8 kGy) soft shell clams

reported a decrease in blood urea

nitrogen (BUN) in the males but not in

the females (Ref. 41). FDA has

concluded that the decreased BUN

levels in this study were not of

toxicological significance for the

following reasons. FDA notes that,

while an elevated BUN level could be a

sign of kidney malfunction (urea is a

metabolite of protein excreted by the

kidney), a decrease in BUN level may

simply indicate less protein consumed.

No significant findings were reported,

however, with respect to clinical

chemistry parameters other than BUN

levels, or in the histopathological

examinations. Moreover, given that the

normal range of BUN levels in dogs is

quite wide, the observed decrease in

BUN level is likely to represent an

artifact of the low statistical power of

the study and is not of toxicological

significance (Ref. 38).

In summary, a large number of

chronic feeding studies have been

conducted in rats, mice, and dogs with

flesh foods irradiated at doses between

6 and 74 kGy. In these studies, no toxic

effects that can be attributed to radiation

treatment were consistently observed.

4. Reproduction and Teratology

Studies

FDA has also reviewed the following

reproduction/teratology studies (Ref. 42)

in which flesh foods, irradiated at doses

of 6 kGy or higher, were fed to

laboratory animals: (1) Studies in which

rats were fed pork irradiated at 56 kGy;

chicken and green beans irradiated at 59

kGy; and fish irradiated at 6 kGy (two

separate studies with fish); (2) a

multigeneration reproduction study and

a teratology study in which mice were

fed chicken irradiated at 59 kGy and 45

kGy, respectively; (3) two studies in

which dogs were fed beef irradiated at

56 kGy; (4) a study in which hamsters

were fed chicken irradiated at 45 kGy;

and (5) a study in which rabbits were

fed chicken irradiated at 45 kGy.

All of these studies, except one,

showed no adverse effects. In one of the

two studies in which fish irradiated at

6 kGy was fed to rats (‘‘the Shillinger

study,’’ Ref. 43), rats in the treated

group were reported to have an

increased incidence of testicular

atrophy and prolonged estrous cycles,

among other findings. The authors

reported no significant difference

between experimental and control

groups with regard to such standard

indices of reproductive function as time

of first births, fertility index, number of

offspring in the litter, or weight of

offspring at birth or at 1 month of age.

In addition, no toxic effects on the

growth or development of three

generations were reported. The authors

stated that some of the findings point to

a protein deficiency.19 However, the

second reproduction study with fish

irradiated at the same dose (‘‘the

Hickman study,’’ Ref. 44) reported no

adverse effects. FDA has concluded that

the effects reported in the Shillinger

study are not attributable to irradiation

for three reasons: (1) The irradiated fish

was stored under inappropriate

conditions, (2) the results of

measurements of blood protein levels
64114 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

are consistent with a nutritionally

inadequate diet, and (3) similar effects

were not seen in the Hickman study.

In summary, the agency concludes

that the available studies of irradiated

flesh foods show no adverse effects on

reproductive or developmental

endpoints that can be attributed to

radiation treatment.

5. Genetic Toxicity Studies

Although chronic feeding studies are

the primary basis for assessing potential

carcinogenicity of a substance, genetic

toxicity tests are often used to screen for

possible carcinogenic effects. A large

variety of genetic toxicity studies with

irradiated chicken, ham, beef, or fish

have been conducted (Ref. 45). All of

these studies report that no genotoxic

effects were observed. FDA agrees that

these studies demonstrate that

irradiated flesh foods are not genotoxic.

6. Summary of the Toxicological

Assessment

As noted previously, chemical

analyses and toxicity studies provide

independent means for assessing

whether there is a reasonable certainty

that irradiation of meat will not present

a toxicological hazard. Chemical

analyses are used to identify substances

produced by irradiation that might

present a risk. Animal feeding studies

and genetic toxicity studies are used to

determine whether toxicants may be

present in irradiated foods, even if not

identified, at levels that would be

harmful.

The agency has carefully reviewed the

data and information submitted in the

petition. The agency has also considered

all the available data and studies in its

files regarding the radiation-induced

chemical changes in flesh foods and the

toxicological effects of irradiated meat

and other irradiated flesh foods (e.g.,

chicken and fish) when consumed in

the diet.

All the available results of chemical

analyses of irradiated flesh foods

support the conclusion that a

toxicological hazard due to

consumption of irradiated flesh foods is

highly unlikely, because no substance

resulting from irradiation has been

found at levels that would suggest any

reason for toxicological concern. The

results of the available toxicological

studies of irradiated flesh foods also

demonstrate that a toxicological hazard

is highly unlikely because no

toxicologically significant adverse

effects attributable to consumption of

irradiated flesh foods were observed in

any of these studies. Thus, the results of

the chemical analyses and the

toxicological studies are entirely

consistent. The agency therefore

concludes, based on all the evidence

before it, that irradiation of meat under

the conditions set forth in the regulation

does not present a toxicological hazard.

D. Nutritional Considerations

The nutritional adequacy of an

irradiated food may be affected by

radiation-induced reductions in the

amounts of essential nutrients in the

food. FDA has carefully reviewed the

data and information submitted in the

petition, as well as other information in

its files, to determine whether

irradiation would have an adverse effect

on the nutritional value of meat.

1. Nutrients in Meat

Flesh foods are consumed primarily

as sources of protein. The so-called ‘‘red

meats,’’ beef in particular, are also rich

sources of iron and phosphorus. Flesh

foods, including red meats, also

contribute significantly to the dietary

intake of B vitamins, except for

thiamine.

Most individual flesh foods, including

meats, provide only a minor portion of

the dietary intake of thiamine (Ref. 46).

The exception to this rule is pork,

which contributes approximately 9

percent of the thiamine in the American

diet (Refs. 46 and 47). The largest

contributors to thiamine intake in the

human diet, however, are grains in

various foods (e.g., cereals; flour in

bread, other baked goods, and pasta)

and legumes.

2. Effects of Irradiation on the Nutrients

in Meat

It is well known that the nutrient

value of the macronutrients in the diet

(proteins, fats, and carbohydrates) is not

significantly altered by irradiation at the

petitioned doses (Refs. 19, 48, and 49).

Minerals (e.g., iron, phosphorus, and

calcium) are also unaffected by

irradiation (Refs. 48 and 49).

Levels of certain vitamins may be

reduced, however, as a result of

irradiation. The extent to which this

occurs depends on the specific vitamin,

the food type, and the conditions of

irradiation. Not all vitamin loss is

significant, however. The extent to

which a reduction in a specific vitamin

level is significant depends on the

relative contribution from the food in

question to the dietary intake of the

vitamin.

Most of the nutrition-related studies

submitted in the petition presented

analyses of vitamin levels in irradiated

flesh foods. These studies covered a

wide range of foods, vitamins, and

irradiation conditions. Most of these

studies focused on the levels of B

vitamins because, as noted, meats and

certain edible organs (e.g., the liver and

the heart) are better sources of B

vitamins than of other vitamins, such as

vitamins C or D, for example. For the

same reason, FDA’s evaluation of the

nutritional adequacy of irradiated meat

and meat byproducts, which considered

all relevant vitamins, focused on the

effects of irradiation on the levels of B

vitamins. In FDA’s evaluation, thiamine

levels received particular attention

because thiamine is one of the vitamins

most susceptible to radiation (Refs. 46

and 50).

In general, the available studies have

reported insignificant effects on the

levels of B vitamins other than thiamine

when flesh foods were irradiated at dose

levels comparable to those proposed in

the subject petition (Refs. 50, 51, and

52). For example, pork irradiated at a

dose of 6.7 kGy showed no detectable

loss in cobalamin level and, when

irradiated at 5 kGy, showed no

detectable loss in niacin level (‘‘the first

Fox study,’’ Ref. 47). Similar results

have been obtained in studies of the

effects of irradiation on other B vitamins

such as pyridoxine and pantothenic

acid (Ref. 52).

Another recently conducted study by

Fox et al., (‘‘the second Fox study,’’ Ref.

53) compared radiation-induced

reductions in B vitamin levels in beef,

lamb, pork, and turkey, all of which

were irradiated at 5 °C in the presence

of oxygen, conditions which would tend

to maximize vitamin loss. The authors

reported that, even under such

conditions, losses of riboflavin resulting

from irradiation were virtually

undetectable at radiation doses up to 3

kGy and that the losses did not differ

significantly among the various flesh

foods. The average incremental loss of

riboflavin at radiation doses above 3

kGy was reported to be 2.5 percent per

kGy, which was judged by the authors

as insignificant. FDA agrees that this

reduction in riboflavin is insignificant

in the context of the total diet (Refs. 46

and 51).

Losses in thiamine levels resulting

from irradiation were also measured in

the second Fox study. Thiamine losses

were detectable at all irradiation doses

tested and differed among the flesh

foods tested, but the range was fairly

narrow: from a low of 8 percent loss per

kGy in lamb to a high of 16 percent loss

per kGy in beef. The incremental

thiamine loss in pork was

approximately 11 percent per kGy above

3 kGy when irradiated at 5 °C in the

presence of oxygen. These results were

consistent with the results of the first

Fox study in which pork irradiated at

4.5 kGy at 0 °C (frozen) sustained losses
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64115

20Spores are the so-called ‘‘resting stage’’ of

certain bacteria in which the bacterial cell becomes

enclosed in a tough, resistant coat as a response to

adverse environmental conditions. On return to less

adverse conditions, the spore can germinate and

revert to the normal vegetative form of the

organism. Under favorable conditions, the

vegetative cells can multiply and, in the case of

certain spore-forming bacteria, produce toxin.

Growth rates of the vegetative cells are influenced

by several factors including temperature, ambient

oxygen level, pH, and the size of the spore

inoculum (numbers of spores present).

21For example, the D values of both L.

monocytogenes and S. aureus fall in the range of

0.40 to 0.48 kGy when irradiated in beef, pork, or

lamb at 5 °C (see, e.g., Refs. 62 and 66). C. jejuni

is more radiation sensitive, with D values in the

range of 0.16 to 0.24 kGy depending on the

particular meat and the conditions of irradiation

(see, e.g., Refs. 63 and 67).

T. gondii tissue cysts are inactivated at a radiation

dose of approximately 0.4 kGy (Ref. 68).

in thiamine levels of circa (ca.) 40

percent (Ref. 47).

Other studies of the effect of

irradiation on thiamine levels in flesh

foods, conducted under a variety of

irradiation conditions, show losses

ranging from approximately 10 to 50

percent over a dose range of 0.6 to 7.3

kGy (Refs. 46, 52, 54, and 55), which is

comparable to the dose range that could,

in actual practice, be used under the

limitations set forth in the regulation. It

is important to note that the highest

thiamine losses (ca. 50 percent for some,

but not all, flesh foods) have occurred

when foods were irradiated at the higher

doses in this range (ca. 7 kGy), in the

nonfrozen state, and/or in the presence

of oxygen.

Irradiation of meat is likely to be

carried out on products that are in

prepackaged form. Meat is commonly

packaged under vacuum or reduced

oxygen levels at the wholesale level and

stored and shipped either refrigerated or

frozen (Ref. 2). As discussed previously,

irradiation of food in the frozen state (or

at reduced temperatures) and under

reduced oxygen levels tends to

minimize vitamin losses (Ref. 48). Thus,

irradiation of most meat, which is likely

to be carried out in an atmosphere of

reduced oxygen content and at low

temperature or in the frozen state, will

tend to result in thiamine losses that are

far less than 50 percent.

Nevertheless, the agency has

conducted an ‘‘extreme case’’

assessment of the potential effect on the

dietary intake of thiamine that would

result if all flesh foods (i.e., meat,

poultry, and fish) were irradiated under

conditions that would tend to maximize

thiamine loss (i.e., such that thiamine

levels in all these foods would be

reduced by 50 percent). The agency has

determined that even in such extreme

and unlikely circumstances, the average

thiamine intake would still be above the

recommended daily allowance (RDA)

and, thus, there would be no deleterious

effect on the total dietary intake of

thiamine as a result of irradiating flesh

foods, including meat (Ref. 46).

3. Summary of the Nutritional

Assessment

As discussed, FDA has concluded that

the effects of irradiation on thiamine,

under the conditions set forth in the

regulation below, will not result in an

adverse effect on the dietary intake of

thiamine. Because the effects of

irradiation on B vitamins other than

thiamine are far less than the effects on

thiamine, FDA also concludes that there

will be no deleterious effect on the total

dietary intake of these other B vitamins

(e.g., riboflavin, niacin, cobalamin). In

addition, as noted, irradiation does not

affect mineral levels, nor, at the doses

set forth in the regulation, the

nutritional quality of the protein in

meat.

FDA therefore concludes, based on all

the evidence before it, that irradiation of

meat under the conditions set forth in

the regulation below will not have an

adverse impact on the nutritional

adequacy of a person’s diet.

E. Microbiological Considerations

Irradiation at the doses requested in

the petition will reduce, but not entirely

eliminate, the microorganisms in or on

meat. Further, because different

microorganisms are affected by

irradiation to different degrees,

irradiation of meat will change the

relative amounts of different

microorganisms present (the

microbiological profile). The

microbiological profile and the storage

conditions of meat influence the growth

patterns of the various microorganisms

found in or on this food. Because

microorganisms remaining in food after

irradiation processing can multiply,

FDA has assessed whether irradiation of

meat under the conditions set forth in

the regulation is likely to alter the

growth patterns of any surviving

microorganisms in such a way as to

result in an increased microbiological

hazard (from increased growth of

pathogens) compared to meat that has

not been irradiated.

1. Microbiological Profile of Raw Meat

Meat is a nutrient-rich substrate that

can support the growth of a variety of

microorganisms. During the initial

processing steps (e.g., slaughter,

skinning, cutting of primals) these

microorganisms are diverse. They

include a wide variety of nonpathogenic

spoilage bacteria, including organisms

from the Pseudomonas-MoraxellaAcinetobacter group, Lactobacillus sp.,

and others. Pathogenic (illness-causing)

microorganisms, including Salmonella

sp., E. coli O157:H7, Listeria

monocytogenes, Staphylococcus aureus,

and others, have also been isolated from

raw meat, generally at relatively low

levels (see Refs. 2, 56, and 57).

Spores20 of certain other pathogenic

microorganisms have been isolated from

raw meat as well. The most commonly

occurring spores in meat are those of C.

perfringens (Refs. 2 and 6). Spores of

Clostridium botulinum have also been

isolated from raw meat; the available

data indicate that both the incidence

and the numbers of C. botulinum spores

are extremely low (Refs. 58, 59, and 60).

Fungal species (i.e., yeasts and molds)

have also been isolated from the

surfaces of raw meat, presumably as a

result of airborne contamination.

Various parasites, including

Toxoplasma gondii and Trichinella

spiralis, both of which can cause serious

foodborne illness, may also be found in

meat.

2. Effects of Irradiation on

Microorganisms in or on Meat

The petitioner provided reports and

published articles describing the effects

of irradiation on the microorganisms in

or on flesh foods. These reports and

published articles provide data on

several microorganisms of relevance,

including various species of Salmonella;

E. coli O157:H7; C. perfringens; S.

aureus; L. monocytogenes; Bacillus

cereus; Campylobacter jejuni; and the

protozoan parasite T. gondii. Taken

together, the available reports and

published articles establish that the

radiation dose necessary to reduce the

initial population of any of the bacterial

pathogens by 90 percent (i.e., the ‘‘D

value’’) ranges from 0.1 kGy to just

under 1 kGy. For any individual

pathogen, the D value varies depending

on such factors as the specific food,

physical state (frozen versus nonfrozen)

of the food, temperature, and ambient

oxygen level.

The D value for Salmonella, for

example, ranges from approximately 0.4

kGy to 0.8 kGy, depending on the

microbial strain and the other factors

mentioned above (Refs. 61, 62, 63, and

64). E. coli O157:H7 is more radiation

sensitive than Salmonella, with a D

value range of approximately 0.2 to 0.4

kGy, depending on the type of flesh

food and the conditions of irradiation

(Refs. 62, 63, and 65). Other studies of

a variety of different pathogens in

different flesh foods yield comparable

results.21
64116 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

D values for the principal

nonpathogenic microorganisms

(spoilage bacteria) commonly found in

or on meat cover a wide range, from

approximately 0.3 to 2.0 kGy (Refs. 69,

70, and 71). Lactobacillus sp. are among

the more radiation-resistant

nonpathogenic spoilage bacteria; the D

values for these bacteria range from

approximately 1 to 2 kGy, depending on

the microbial strain and the conditions

of irradiation (Ref. 71).

In the case of spore-forming bacteria,

the spores and vegetative cells are

affected by irradiation to different

degrees. Spores are generally more

resistant to the effects of radiation than

vegetative cells. For example, the D

values for vegetative cells of various

strains of C. perfringens range from 0.6

to 0.8 kGy (Refs. 72 and 73), comparable

to the D values for most of the

pathogens discussed above, while the D

values for the spores of C. perfringens

range from 1.2 to 1.8 kGy (Ref. 74). The

spores of C. botulinum are more

radiation-resistant; the D values for the

spores of various strains of C. botulinum

range from approximately 2 to 4 kGy

(Refs. 60 and 74).

The agency has reviewed the data and

information described previously as

well as other information in its files and

has determined that irradiation at doses

of up to 4.5 kGy for refrigerated product

and doses of up to 7.0 kGy for frozen

product will significantly reduce the

number of pathogenic microorganisms

in or on meat (Ref. 75). Under the

conditions set forth in the regulation

below, reductions in Salmonella levels,

for example, could be approximately

100,000-fold in refrigerated beef

irradiated at 4.5 kGy. Because E. coli is

more sensitive to the effects of

irradiation, reductions in the levels of

that microorganism would be even

greater in beef irradiated under these

same conditions. The levels of most

spoilage microorganisms on meat will

also be significantly reduced at the

petitioned doses, resulting in an

extension of the shelf-life of the

product.

However, while irradiation at the

petitioned doses significantly reduces

the numbers of many pathogenic and

spoilage bacteria, its effect in reducing

the numbers of relatively radiationresistant spores of other pathogenic

bacteria (e.g., C. botulinum, with D

values of approximately 2 to 4 kGy), is

less. Therefore, FDA has carefully

examined the effects of radiationinduced changes in the microbiological

profile of meat on the growth patterns

of surviving microorganisms to

determine whether the microbiological

safety of meat irradiated under the

conditions set forth in the regulation

would be adversely affected. In FDA’s

evaluation, C. botulinum received

particular attention both because C.

botulinum spores are the most radiationresistant of the pathogens found in meat

and because the illness induced by

botulinal toxin is so severe.

3. Growth Patterns of Microorganisms

in or on Raw Meat

As noted previously, meat is a

substrate that can, in principle, support

the growth of a variety of

microorganisms. The conditions under

which meat is stored (e.g., temperature,

ambient atmosphere, pH) influence the

growth patterns of different

microorganisms, however, affecting both

the types and numbers of different

microorganisms that are likely to be

found in or on meat at any given time.

Meat is chilled and subsequently

stored under refrigeration (generally 37

to 45 °F) immediately following the

initial processing steps. During cold

storage, the predominant

microorganisms are the spoilage

bacteria, primarily Pseudomonas sp.,

that are capable of growth at these

temperatures. If the chilled meat is

packaged in an environment of reduced

oxygen content, other spoilage bacteria,

such as Lactobacillus sp., Brochothrix

thermosphacta, and other lactic acidproducing microorganisms,

predominate (Refs. 2 and 56).

The growth of C. perfringens,

Salmonella, and E. coli is well

controlled by cooling meat quickly after

slaughter and maintaining the product

at refrigerated temperatures during

subsequent transport and storage. None

of these pathogens is normally capable

of growth in meat stored under

refrigeration. In addition, competition

with the more numerous and fastergrowing spoilage bacteria that

predominate at refrigeration

temperatures further inhibits the growth

of these pathogens. Both Salmonella

and E. coli O157:H7 are capable of

significant growth, however, in meat

stored above refrigeration temperatures

(‘‘temperature abuse’’ conditions; above

50 °F). Temperature control is thus a

primary tool in reducing the growth of,

and consequently, the risk from, these

pathogens.

Growth of C. botulinum is influenced

by several factors in addition to

temperature, including the availability

of oxygen, pH of the food, and the

numbers of C. botulinum spores in

relation to the types and numbers of

competing microorganisms.

Temperature control is, however, the

single most important factor in

controlling the growth of the strains of

C. botulinum that have been most

frequently (albeit still rarely and in low

numbers) isolated from meat in the

United States (Refs. 59, 60, and 76) In

this regard, the same temperature

control regimen used to control the

growth of other pathogens such as

Salmonella, E. coli O157:H7, and C.

perfringens also works well to inhibit

growth of, and toxin production by, C.

botulinum in meat. Temperature abuse

can lead to growth and toxin production

by C. botulinum; however, this typically

takes several weeks to occur, even at

temperatures of approximately 60 °F. By

this time, signs of spoilage (e.g., putrid

odor, slimy texture), produced primarily

by the faster-growing and more

numerous nonpathogenic spoilage

bacteria, are evident. The objectionable

odor and texture of spoiled meat is a

signal that typically inhibits consumers

from eating the product. Reports of

botulism resulting from consumption of

such meat are rare and, generally, have

been limited to ethnic groups that favor

these foods (see Refs. 59, 76, and 77).

In summary, maintaining meat at low

storage temperatures is the primary

method for controlling the growth of

pathogenic microorganisms and, thus,

for reducing the risk of disease from

pathogenic microorganisms in or on

meat.

4. Effects of Irradiation on Growth

Patterns of Microorganisms in or on

Meat

As noted above, radiation-induced

changes in the microbiological profile of

meat have the potential to affect the

growth patterns of the various

microorganisms in or on meat. FDA has

evaluated whether irradiation would

result in significantly altered microbial

growth patterns in meat (e.g.,

significantly increased growth of

pathogens) such that irradiated meat

would present an increased

microbiological hazard compared to

meat that had not been irradiated. The

agency has reviewed data and

information submitted in the petition, as

well as other information in its files,

regarding the effects of irradiation,

temperature abuse conditions, and

ambient oxygen levels on the

microbiological profile of meat.

Because C. botulinum spores are the

most resistant to the effects of

irradiation and would thus be more

likely to survive irradiation than other

pathogens and most spoilage bacteria,

and because the illness associated with

botulinal toxin is so severe, FDA, in its

evaluation, focused particularly on the

effects of irradiation on the probability

of significantly increased growth of, and

subsequent toxin production by, C.

botulinum.
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64117

22 In the case of Lactobacillus, production of

lactic acid, which lowers the pH of the meat, is a

contributing factor in inhibiting the growth of

various pathogens, including C. botulinum (see,

e.g., Refs. 59 and 71).

With respect to most of the significant

pathogens found in or on meat, other

than C. botulinum (e.g., Salmonella and

E. coli O157:H7), FDA concludes that

the probability of significant growth of

these pathogens in irradiated meat

stored under adequate temperature

control is extremely remote for two

reasons. First, these pathogens typically

require temperatures of 50 °F or higher

for significant growth. Second, as noted

above, most of the pathogens in or on

meat are more sensitive to the effects of

irradiation than many of the common

spoilage microorganisms (e.g.,

Lactobacillus, with D values of 1 to 2

kGy). Because these pathogens are

sensitive to the effects of irradiation,

FDA expects that irradiation under the

conditions set forth in the regulation

below will reduce the numbers of these

pathogens to a far greater extent than it

will reduce the numbers of the fastergrowing spoilage microorganisms that

compete with, and inhibit the growth of,

pathogens at refrigeration temperatures.

Nevertheless, FDA has also

considered the effects of temperature

abuse on growth of these pathogens

(e.g., Salmonella, E. coli O157:H7, C.

perfringens) in irradiated meat. In one of

the studies submitted in the petition

(Ref. 72), pork was packaged and

irradiated at 1.75 kGy under a modified

atmosphere containing no oxygen

following inoculation with high levels

of any one of several pathogens. In this

study, the authors reported that growth

of these pathogens (Salmonella, E. coli,

and C. perfringens, among others), was,

in fact, decreased by irradiation even

when temperature conditions were

favorable for growth (approximately 60

°F).

With respect to C. botulinum, FDA

concludes that the probability for

significant growth of, and toxin

production by, C. botulinum in

irradiated meat stored under adequate

temperature control (properly

refrigerated or frozen) is extremely

remote for several reasons. First, as

noted, C. botulinum spores occur with

extremely low frequency and in

extremely low numbers in meat; these

numbers will be further reduced by

irradiation at the petitioned doses.

Research has established that the size of

the spore inoculum (numbers of spores

present in the food) is an important

factor in the growth of, and toxin

production by, C. botulinum; reduced

numbers of spores generally result in a

decreased probability that growth

sufficient for toxin production will

occur (Ref. 59).

Second, most strains of C. botulinum

that have been found in meat do not

grow and produce toxin under

refrigeration conditions appropriate for

transport and storage of flesh foods. The

available data show that growth and

subsequent toxin production by C.

botulinum in meat requires significantly

elevated temperatures (50 to 55 °F, or

higher) (Refs. 59, 60, and 77). Even

under reduced ambient oxygen levels

(conditions that favor the growth of C.

botulinum), elevated temperatures are

still required for significant growth and

toxin production. Irradiation does not

enable C. botulinum to grow at

refrigeration temperatures; elevated

temperatures on the order of 50 to 55 °F

are required, whether meat is irradiated

or not. Nevertheless, the agency has also

considered whether, in the absence of

temperature control, irradiation could

increase the likelihood that C.

botulinum could grow and produce

toxin without the signs of spoilage

familiar to the consumer that discourage

consumption of spoiled meat.

One study submitted in the petition

(Ref. 78) investigated the effect of

irradiation, at a dose of 3 kGy, on the

patterns of microbial growth and

spoilage in vacuum-packaged pork loins

stored under conditions of proper

refrigeration (2 to 4 °C to simulate

wholesale storage, and 5 to

7 °C to simulate retail storage) and

under conditions of severe temperature

abuse (24 to 25 °C). Shelf-life of pork

stored under refrigeration conditions

was extended by irradiation. The

authors found that both irradiated pork

and pork that had not been irradiated

spoiled rapidly under conditions of

severe temperature abuse and that the

same types of microorganisms were

responsible for spoilage in both

irradiated pork and pork that had not

been irradiated. The authors concluded

that the concurrent and similar

increases that they observed in the

numbers of lactobacilli and other

bacteria in the temperature-abused,

vacuum-packaged irradiated pork

indicated that sufficient spoilage

organisms survived irradiation to bring

about spoilage after severe temperature

mishandling. FDA concurs in these

conclusions (Ref. 77).

In several other studies submitted in

the petition (‘‘the Lambert studies,’’

Refs. 79a through 79c), pork was

packaged and irradiated at a dose of 1

kGy under reduced ambient oxygen

levels following inoculation with high

levels of C. botulinum spores. In these

studies, storage at elevated

temperatures, equivalent to

approximately 60 °F, was required for C.

botulinum to grow and produce toxin;

no toxin was detected in pork stored at

approximately 41 °F . The authors

concluded that irradiation at 1 kGy

significantly delayed toxin production

by C. botulinum (Refs. 79a and 79b).

The authors of these studies also

reported that signs of spoilage in the

irradiated pork appeared at least 1 week

before, and under certain conditions, up

to 5 weeks before, toxin was detected

(Ref. 79a).

The data and information in the

Lambert studies show that even when

the levels of C. botulinum spore

inoculum are high and the ambient

oxygen level low (conditions that, as

noted, would tend to increase growth

and toxin production), toxin production

was preceded by signs of spoilage in the

irradiated meat. These data also

demonstrate that storage at sustained

elevated temperatures, for several

weeks, are required for growth of, and

toxin production by, C. botulinum in

irradiated pork.

Third, other data and information also

show that various species of other

microorganisms commonly found on

meat, particularly spoilage bacteria (e.g.,

Lactobacillus sp.22 and others), survive

irradiation in sufficient numbers to

grow and inhibit growth of, and toxin

production by, C. botulinum in both

refrigerated and temperature-abused

irradiated meats (Refs. 71, 80, and 81).

5. Summary of the Microbiological

Assessment

FDA has reviewed the data and

information submitted in the petition

and has considered all the available data

and information in its files relevant to

an assessment of the microbiological

safety of the irradiation of meat. In

particular, FDA has carefully examined

the effects of radiation-induced changes

in the microbiological profile of meat on

the growth patterns of any surviving

microorganisms, including C.

botulinum, to determine whether the

microbiological safety of meat would be

adversely affected by irradiation under

the conditions set forth in the regulation

below.

As discussed previously in this

document, the agency has determined

that irradiation of meat and meat

byproducts under the conditions set

forth in the regulation below will not

result in any additional health hazard

from C. botulinum (Ref. 75). Likewise,

as discussed previously, FDA has also

determined that irradiation will not

result in any additional hazard from

common pathogens other than C.

botulinum. Therefore, the agency

concludes, based on all the evidence

before it, that irradiation of meat under
64118 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

23 In the preamble to the rule that established the

new requirement for the development and

implementation of HACCP systems in meat and

poultry plants, FSIS addressed the need for cooling

and chilling requirements for raw meat and poultry.

In the final rule, FSIS stated that, with respect to

regulation of time and temperature control, it would

be best to have, as a performance standard, a

maximum temperature for products being shipped

into commerce, and at which raw products in

commerce must be maintained. This standard

would be applicable to all persons who handle such

product before the product reaches the consumer.

FSIS concluded, however, that development of such

a performance standard required the acquisition of

additional information, and indicated that it would

engage in further rulemaking in this area.

the conditions set forth in the regulation

below will not result in a

microbiological hazard.

IV. Current Good Manufacturing

Practice Considerations

As noted, the proper processing,

handling, and storage of meat and meat

byproducts, irradiated or not, are

necessary to ensure their safety. With

respect to the processing and handling

of both meat and poultry, USDA/FSIS

has recently established specific

requirements applicable to meat and

poultry establishments designed to

reduce the occurrence and numbers of

pathogenic microorganisms on meat and

poultry products and thus, to reduce the

incidence of foodborne illness

associated with these products (61 FR

38806, July 25, 1996). Among other

things, these new regulations require

that each meat and poultry

establishment develop and implement

written standard operating procedures

for sanitation (Sanitation SOP’s, SSOP’s)

and that each establishment also

develop and implement a system of

preventive controls, known as HACCP

(Hazard Analysis and Critical Control

Points), which is designed to improve

the safety of their products.

FSIS has stated that it intends to use

HACCP systems as a framework for the

modernization of the meat and poultry

inspection system (61 FR 33806).

HACCP systems are not intended to

replace good manufacturing practices

(GMP’s), but rather to be used as the

basis of an approach to food safety that

focuses on hazard prevention and

control. HACCP, GMP’s, SSOP’s, and

other tools and interventions all have a

place in ensuring the safety of meat.

FSIS has stated that it anticipates that

the adoption of HACCP systems by the

meat industry as a whole will

significantly increase the safety of meat

products and reduce the risk of

foodborne illness (61 FR 33806).

A. Temperature control

As noted previously, proper

temperature control is critical in

ensuring the safety of meat, meat

byproducts, and meat food products,

whether or not they are irradiated.

FDA’s regulations regarding CGMP’s

(part 110 (21 CFR part 110)) stipulate

that the temperature of refrigerated

foods not exceed 45 °F

(§ 110.80(b)(3)(i)). With respect to meat

products specifically, FDA’s Model

Food Code, which is offered for

adoption by States and other

government entities that exercise

primary regulatory authority over food

service, retail food stores, and food

vending machine operations,

recommends that meat products be

stored at 41°F or less. There are no data

or other information that suggest that, in

order to ensure their safety, irradiated

meat products require different

temperature controls than meat

products that have not been irradiated.

Moreover, FSIS, under its regulatory

authority over meat processing plants,

can establish specific requirements with

respect to temperature control of

irradiated meat, meat byproducts, and

meat food products.23 FDA concludes

that its regulation should allow for

flexibility in this regard. Therefore, the

regulation does not establish specific

requirements with respect to

temperature control of irradiated meat,

meat byproducts, and meat food

products.

B. Consideration of the Need for

Establishment of a Minimum Dose

FDA has established, in § 179.25,

general provisions defining CGMP for

the use of irradiation in the treatment of

food. This regulation discusses

requirements such as recordkeeping and

the need for a scheduled process for

food irradiation. Among other things,

§ 179.25 also requires that ‘‘Food treated

with ionizing radiation shall receive the

minimum radiation dose reasonably

required to accomplish its intended

effect * * *.’’ (Section 179.25(b).)

FDA notes that the minimum dose

necessary to control pathogenic

organisms on food can vary with the

particular microorganism, the specific

food, and with the microbial load on the

food. In its decision to permit the

irradiation of poultry at doses up to 3

kGy, FDA explicitly considered these

facts and noted that FSIS, based on its

regulatory authority over poultry

processing plants, could establish a

minimum dose, consistent with CGMP,

for controlling pathogenic organisms in

or on the products processed in such

plants. The agency also concluded that

FSIS should be free to do so without

having to submit a new petition for an

amendment to the regulation, as long as

any requirements complied with the

applicable sections of part 179.

Similarly, with respect to the

processing of meat, meat byproducts,

and meat food products, FDA is not

establishing a minimum required dose.

The agency concludes that different

doses could be appropriate, in different

circumstances, for achieving the desired

technical effect and that FDA’s

regulation should allow for flexibility in

this regard. Moreover, FSIS, under its

regulatory authority over meat

processing plants, can establish a

minimum dose, consistent with GMP,

for controlling pathogenic organisms in

or on the products processed in these

plants. FSIS should be free to do so

without having to submit a petition for

an amendment to FDA’s regulation, as

long as any FSIS requirements comply

with the applicable sections of part 179.

V. Labeling

Meat, meat byproducts, and meat food

products are subject to the Federal Meat

Inspection Act (21 U.S.C. 601 et seq.).

Therefore, the labeling of these products

irradiated under the conditions set forth

in the regulation must comply with any

requirements imposed by USDA/FSIS

under its authority to approve the

labeling of such products.

VI. Conclusion of Safety

FDA has evaluated the data in the

petition and other material in its files

relevant to the proposed use of a source

of radiation to treat meat, meat

byproducts, and certain meat food

products. Based on all the evidence

before it, FDA concludes that irradiation

of these products under the conditions

set forth in the regulation below will not

present a toxicological hazard, will not

present a microbiological hazard, and

will not adversely affect the nutritional

adequacy of such products. Therefore,

the agency concludes that irradiation of

meat, meat byproducts, and meat food

products under the conditions set forth

in the regulation below is safe.

Accordingly, FDA has determined that

part 179 should be amended.

In accordance with § 171.1(h) (21 CFR

171.1(h)), the petition and the

documents that FDA considered and

relied upon in reaching its decision to

approve the petition are available for

inspection at the Center for Food Safety

and Applied Nutrition by appointment

with the listed contact person. As

provided in § 171.1(h), the agency will

delete from the documents any

materials that are not available for

public disclosure before making the

documents available for inspection.
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64119

VII. Environmental Impact

The agency has carefully considered

the potential environmental effects of

this action. FDA has concluded that the

action will not have a significant impact

on the human environment, and that an

environmental impact statement is not

required. The agency’s finding of no

significant impact and the evidence

supporting that finding, contained in an

environmental assessment, may be seen

in the Dockets Management Branch

(address above) between 9 a.m. and 4

p.m., Monday through Friday.

VIII. Objections

Any person who will be adversely

affected by this regulation may at any

time on or before January 2, 1998 file

with the Dockets Management Branch

(address above) written objections

thereto. Each objection shall be

separately numbered, and each

numbered objection shall specify with

particularity the provisions of the

regulation to which objection is made

and the grounds for the objection. Each

numbered objection on which a hearing

is requested shall specifically so state.

Failure to request a hearing for any

particular objection shall constitute a

waiver of the right to a hearing on that

objection. Each numbered objection for

which a hearing is requested shall

include a detailed description and

analysis of the specific factual

information intended to be presented in

support of the objection in the event

that a hearing is held. Failure to include

such a description and analysis for any

particular objection shall constitute a

waiver of the right to a hearing on the

objection. Three copies of all documents

shall be submitted and shall be

identified with the docket number

found in brackets in the heading of this

document. Any objections received in

response to the regulation may be seen

in the Dockets Management Branch

between 9 a.m. and 4 p.m., Monday

through Friday.

IX. References

The following sources are referred to

in this document. References marked

with an asterisk (*) have been placed on

display in the Dockets Management

Branch (address above) and may be seen

by interested persons between 9 a.m.

and 4 p.m., Monday through Friday.

References without an asterisk are not

on display; they are available as

published articles and books.

1. Weingold, S. E., J. J. Guzewich, and J.

F. Fudala, ‘‘Use of Foodborne Disease Data

for HACCP Risk Assessment,’’ Journal of

Food Protection, 57:820–830, 1994.

2. National Advisory Committee on

Microbiological Criteria for Foods, ‘‘Generic

HACCP for Raw Beef,’’ Food Microbiology,

10:449–488, 1993.

3. Griffin, P. M. and R. V. Tauxe, ‘‘The

Epidemiology of Infections Caused by

Escherichia coli O157:H7, Other

Enterohemorrhagic E. coli, and the

Associated Haemolytic Uraemic Syndrome,’’

Epidemiology Reviews, 13:60–98, 1991.

4. Boyce, T. G., D. L. Swerdlow, and P. M.

Griffin, ‘‘Escherichia coli O157:H7 and the

Hemolytic-Uremic Syndrome,’’ New England

Journal of Medicine, 333(6):364–368, 1995.

5. D’Aoust, J. Y.,‘‘Salmonella Species,’’ pp.

129–158, in Food Microbiology:

Fundamentals and Frontiers, M. P. Doyle, L.

R. Beuchat, and T. J. Montville, eds., ASM

Press, Washington, DC, 1997.

6. McClane, B. A., ‘‘Clostridium

perfringens,’’ pp. 305–326, in Food

Microbiology: Fundamentals and Frontiers,

M. P. Doyle, L. R. Beuchat, and T. J.

Montville, eds., ASM Press, Washington, DC,

1997.

7. Merritt, C., Jr., ‘‘Qualitative and

Quantitative Aspects of Trace Volatile

Components In Irradiated Foods and Food

Substances,’’ Radiation Research Reviews,

3:353–368, 1972.

*8. Morehouse, K. M., ‘‘The Quantitative

Determination of Radiolytically Generated

Hydrocarbons in Meats,’’ final report for U.S.

Army, Natick Research Development and

Engineering Center, Sustainability

Directorate, under Interagency Agreement

FDA 224–93–2448.

9. Merritt, C., Jr., et al., ‘‘Effect of Radiation

Parameters on the Formation of Radiolysis

Products in Meat Substances,’’ Journal of

Agricultural and Food Chemistry, 26:29–35,

1978.

10. Taub, I. A. et al., ‘‘Factors Affecting

Radiolytic Effects In Food,’’ Radiation

Physics and Chemistry, 14:639–653, 1979.

11. Diehl, J. F., ‘‘Radiolytic Effects in

Foods,’’ pp. 279–357, in Preservation of

Foods By Ionizing Radiation, Vol. 1, E. S.

Josephson and M. S. Peterson, eds., CRC

Press, Boca Raton, Fl., 1982.

12. Diehl, J. F., ‘‘Chemical Effects of

Ionizing Radiation,’’ pp. 43–88, in Safety of

Irradiated Foods, Marcel Dekker, New York,

1995.

13. Taub, I. A. et al., ‘‘Effect of Irradiation

on Meat Proteins,’’ Food Technology, pp.

184–193, May 1979.

14. Merritt, C., Jr., and I. A. Taub,

‘‘Commonality and Predictability of

Radiolytic Products In Irradiated Meats,’’ pp.

27–58, in Recent Advances In Food

Irradiation, P. S. Elias and A. J. Cohen, eds.,

Elsevier, Amsterdam, 1983.

15. Delincee, H., ‘‘Recent Advances in the

Radiation Chemistry of Proteins,’’ pp. 129–

148, in Recent Advances in Food Irradiation,

P. S. Elias and A. J. Cohen, eds., Elsevier,

Amsterdam, 1983.

16. Urbain, W. M., ‘‘Radiation Chemistry of

Proteins,’’ pp. 63–130, in Radiation

Chemistry of Major Food Components, P. S.

Elias and A. J. Cohen, eds., Elsevier,

Amsterdam, 1977.

17. Simic, M. G., ‘‘Radiation Chemistry of

Water Soluble Food Components,’’ pp. 1–73,

in Preservation of Food by Ionizing

Radiation, Vol. 2, E. S. Josephson and M. S.

Peterson, eds., CRC Press, Boca Raton, Fl.,

1982.

18. Taub, I. A., ‘‘Reaction Mechanisms,

Irradiation Parameters, and Product

Formation,’’ pp. 125–166, in Preservation of

Food by Ionizing Radiation, Vol. 2, E. S.

Josephson and M. S. Peterson, eds., CRC

Press, Boca Raton, Fl., 1982.

19. Underdal, B., et al., ‘‘The Effect of

Ionizing Radiation on the Nutritional Value

of Fish (Cod) Protein,’’ LebensmittelWissenschaft Technologie, 6:90–93, 1973.

20. Josephson et al., ‘‘Nutritional Aspects

of Food Irradiation: An Overview,’’ Journal of

Food Processing and Preservation, 2:299–

313, 1979.

21. Nawar, W. W., ‘‘Radiation Chemistry of

Lipids,’’ pp. 21–62, in Radiation Chemistry of

Major Food Components, P. S. Elias and A.

J. Cohen, eds., Elsevier, Amsterdam, 1977.

22. Nawar, W. W., ‘‘Volatiles from Food

Irradiation,’’ Food Reviews International,

2:45–78, 1986.

23. Nawar, W. W., ‘‘Radiolysis of

Nonaqueous Components of Foods,’’ pp. 75–

124, in Preservation of Food by Ionizing

Radiation, Vol. 2, E. S. Josephson and M. S.

Peterson, eds., CRC Press, Boca Raton, Fl.,

1982.

24. Morehouse, K. M. and Yuoh Ku, ‘‘Gas

Chromatographic and Electron Spin

Resonance Investigations of γ-Irradiated

Shrimp,’’ Journal of Agricultural and Food

Chemistry, 40:1963–1971, 1992.

25. Delincee, H., ‘‘Recent Advances in the

Radiation Chemistry of Lipids,’’ pp. 89–114,

in Recent Advances in Food Irradiation, P. S.

Elias and A. J. Cohen, eds., Elsevier,

Amsterdam, 1983.

*26a. Chinn, H. I. (Chairman, Select

Committee on Health Aspects of Irradiated

Beef), ‘‘Evaluation of Health Aspects of

Certain Compounds Found in Irradiated

Beef,’’ Federation of American Societies for

Experimental Biology (FASEB), Bethesda,

MD, 1977.

*26b. Chinn, H. I., ‘‘Supplement I. Further

Toxicological Considerations of Volatile

Compounds,’’ FASEB, Bethesda, MD, 1979.

*26c. Chinn, H. I., ‘‘Supplement II.

Possible Radiolytic Compounds,’’ FASEB,

Bethesda, MD, 1979.

27. Nawar, W. W., ‘‘Thermal Degradation

of Lipids. A Review,’’ Journal of Agricultural

and Food Chemistry, 17(1):18–21, 1969.

28. Watt, B. K. and A. L. Merrill,

Composition of Foods, Agriculture Handbook

No. 8, Consumer and Food Economics

Institute, Agriculture Research Service,

United States Department of Agriculture,

Washington, DC, 1975.

29. Krause, M. V. and M. A. Hunscher,

Food, Nutrition, and Diet Therapy, W. B.

Saunders Co., Philadelphia, 1972, pp. 665–

677, (table adapted from ‘‘Amino Acid

Content of Foods,’’ Home Economics

Research Report No. 4, U.S. Department of

Agriculture, 1968.)

*30. Brunetti, A. P., et al.,

‘‘Recommendations for Evaluating the Safety

of Irradiated Foods,’’ final report prepared for

the Director, Bureau of Foods, FDA, July

1980.

*31. WHO, ‘‘Wholesomeness of Irradiated

Food: Report of a Joint FAO/IAEA/WHO

Expert Committee,’’ World Health

Organization Technical Report Series, No.

659, World Health Organization, Geneva,

1981.
64120 Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations

*32. FAO, ‘‘Codex General Standard for

Irradiated Foods and Recommended

International Code of Practice for the

Operation of Radiation Facilities for the

Treatment of Foods,’’ Codex Alimentarius

Commission, FAO/WHO, CAC/Vol. XV, Ed.1,

Rome, 1984.

*33. WHO, ‘‘Safety and Nutritional

Adequacy of Irradiated Food,’’ World Health

Organization, Geneva, 1994.

*34a. Memorandum to the file, FAP

4M4428, from D. Hattan, FDA, dated

November 18, 1997.

*34b. Memorandum from H. Irausquin,

FDA, to P. Hansen, FDA, dated April 20,

1995.

*35. Memorandum from Food Additives

Evaluation Branch, FDA, to Petitions Control

Branch, FDA, dated December 28, 1982, with

attached Tab A, dated September 15, 1982.

*36. Memorandum to the file, FAP

4M4428—References for long-term feeding

studies, from W. Trotter, FDA, dated

November 10, 1997.

*37. Phillips, A. W., R. Newcomb, and D.

Shanklin, ‘‘Long-term Rat Feeding Studies:

Irradiated Chicken Stew and Cabbage,’’ U.S.

Army Unpublished Contract Report No. DA–

49–007–MD–783, 1961.

*38. Memorandum to the file, FAP

4M4428, from P. Hansen, FDA, dated October

31, 1997.

*39. Read, M. S., H. F. Kraybill, and N. F.

Witt, ‘‘Successive Generation Rat Feeding

Studies with a Composite Diet of GammaIrradiated Foods,’’ Toxicology and Applied

Pharmacology, 3:153, 1961.

*40. Monsen, H., ‘‘Heart Lesions in Mice

Induced by Feeding Irradiated Foods,’’

Federation Proceedings, 19:1031, 1960.

*41. Fegley, H. C. and R. E. Edmonds, ‘‘To

Examine the Wholesomeness of Irradiated

Soft-Shell Clams (Mya Arenaria) in Dogs,’’

Food Irradiation Information, Food and

Agriculture Organization/International

Atomic Energy Agency, 6 (Suppl.):111, 1976.

*42. Memorandum to the file, FAP

4M4428—References for reproduction and

teratology studies, from W. Trotter, FDA,

dated November 10, 1997.

*43. Shillinger, I. and I. N. Osipova, ‘‘The

Effect of Fresh Fish, Exposed to Gamma

Radiation on the Organism of Albino Rats,’’

Voprosy Pitanija, 29(5):45, 1970.

*44. Hickman, J. R., ‘‘Studies on the

Wholesomeness of Irradiated Fish,

Reproduction,’’ Harwell, U.K. Atomic Energy

Authority, Technical Report AERE–R–6016,

1969.

*45. Memorandum to the file, FAP

4M4428—References for the mutagenicity

and genotoxicity studies, from W. Trotter,

FDA, dated November 10, 1997.

*46. Memorandum from J. Vanderveen,

FDA, to P. Hansen, FDA, dated March 11,

1996.

47. Fox, J. B., Jr., et al., ‘‘Effect of Gamma

Irradiation on the B Vitamins of Pork Chops

and Chicken Breasts,’’ International Journal

of Radiation Biology, 55:689–703, 1989.

48. Diehl, J. F., ‘‘Nutritional Adequacy of

Irradiated Foods,’’ pp. 241–282, in Safety of

Irradiated Foods, Marcel Dekker, New York

1995.

49. Josephson, E. S. and M. H. Thomas,

‘‘Nutritional Aspects of Food Irradiation: An

Overview,’’ Journal of Food Processing and

Preservation, 2:299–313, 1978.

50. Tobback, P.P., ‘‘Radiation Chemistry of

Vitamins,’’ pp. 187–220 in Radiation

Chemistry of Major Food Components, P. S.

Elias and A. J. Cohen, eds., Elsevier,

Amsterdam, 1977.

*51. Memorandum from S. Carberry, FDA,

to P. Hansen, FDA, dated January 12, 1995.

52. Thayer, D. W., J. B. Fox, Jr., and L.

Lakritz, ‘‘Effects of Ionizing Radiation on

Vitamins,’’ pp. 285–325, in Food Irradiation,

S. Thorne, ed., Elsevier Applied Science

Publishers, London, 1991.

53. Fox, J. B., et al., ‘‘Effect of Gamma

Radiation on Thiamin and Riboflavin in Beef,

Lamb, Pork, and Turkey,’’ Journal of Food

Science, 60(3):596–598, 1994.

54. Srinivas, H. et al., ‘‘Nutritional and

Compositional Changes in DehydroIrradiated Shrimp,’’ Journal of Food Science,

39:807–811, 1974.

55. Kennedy, T. S. and F. J. Ley, ‘‘Studies

on the Combined Effect of Gamma Radiation

and Cooking on the Nutritional Value of

Fish,’’ Journal of Science Food and

Agriculture, 22:146–148, 1971.

56. Lambert, A. D., J. P. Smith, and K. L.

Dodds, ‘‘Shelf Life Extension and

Microbiological Safety of Fresh Meat: A

Review,’’ Food Microbiology, 8:267–297,

1991.

57. Doyle, M. P. and J. L. Schoeni,

‘‘Isolation of Escherichia coli O157:H7 from

Retail Fresh Meats and Poultry,’’ Applied

and Environmental Microbiology, 53:2394–

2396, 1987.

58. Dodds, K. L., ‘‘Clostridium botulinum

in Foods,’’ pp. 53–68 in Clostridium

botulinum: Ecology and Control in Foods, A.

H. W. Hauschild, and K. L. Dodds, eds.,

Marcel Dekker, New York, 1993.

59. Lucke, F–K. and T. A. Roberts, ‘‘Control

in Meat and Meat Products,’’ pp. 177–207, in

Clostridium botulinum: Ecology and Control

in Foods, A. H. W. Hauschild, and K. L.

Dodds, eds., Marcel Dekker, New York, 1993.

60. International Commission on

Microbiological Specification for Foods,

Microorganisms in Foods 5. Characteristics of

Microbial Pathogens, Blackie Academic and

Professional, London, 1996.

61. Thayer, D. W., et al., ‘‘Radiation

Resistance of Salmonella,’’ Journal of

Industrial Microbiology, 5:383–390, 1990.

62. Thayer, et al., ‘‘Variations in Radiation

Sensitivity of Foodborne Pathogens

Associated with the Suspending Meat,’’

Journal of Food Science, 60(1):63–67, 1994.

63. Clavero, M. R. S., et al., ‘‘Inactivation

of Escherichia coli O157:H7, Salmonellae

and Campylobacter jejuni in Raw Ground

Beef by Gamma Irradiation,’’ Applied and

Environmental Microbiology, 60:2069–2075,

1994.

64. Han, L.–B., M.–H. Liew, and L.–T. Yeh,

‘‘Preservation of Grass Prawns by Ionizing

Radiation,’’ Journal of Food Protection,

55:198–202, 1992.

65. Thayer, D. W. and G. Boyd,

‘‘Elimination of Escherichia coli O157:H7 in

Meats by Gamma Irradiation,’’ Applied and

Environmental Microbiology, 59:1030–1034,

1993.

66. Monk, D. J., et al., ‘‘Irradiation

Inactivation of Listeria monocytogenes and

Staphylococcus aureus in Low- and High-fat,

Frozen and Refrigerated Ground Beef,’’

Journal of Food Protection, 57:969–974, 1994.

67. Lambert, J. D. and R. B. Maxcy, ‘‘Effects

of Gamma Radiation on Campylobacter

jejuni,’’ Journal of Food Science, 49:665–667,

1984.

68. Dubey, J. P. and D. W. Thayer, ‘‘Killing

of Different Strains of Toxoplasma gondii

Tissue Cysts by Irradiation Under Defined

Conditions,’’ Journal of Parasitology, 80(5):

764–767, 1994.

69. Ingram, M. and J. Farkas,

‘‘Microbiology of Foods Pasteurized by

Ionizing Radiation,’’ Acta Alimentaria,

6:123–185, 1977.

70. Tallentire, A., ‘‘The Spectrum of

Microbial Radiation-Sensitivity,’’ Radiation

Physics and Chemistry, 15:83–89, 1980.

71. Hastings, J. W., W. H. Holzapfel, and

J. G. Niemand, ‘‘Radiation Resistance of

Lactobacilli Isolated from Radurized Meat

Relative to Growth and Environment,’’

Applied and Environmental Microbiology,

52(4):898–901, 1986.

72. Grant, I. R. and M. F. Patterson, ‘‘Effect

of Irradiation and Modified Atmosphere

Packaging on the Microbiological Safety of

Minced Pork Under Temperature Abuse

Conditions,’’ International Journal of Food

Science and Technology, 26:521–533, 1991.

73. Grant, I. R. and M. F. Patterson,

‘‘Sensitivity of Foodborne Pathogens to

Irradiation in the Components of a Chilled

Ready Meal,’’ Food Microbiology, 9:95–103,

1992.

74. Grecz, N., D. B. Rowley, and A.

Matsuyama, ‘‘The Action of Radiation on

Bacteria and Viruses,’’ pp. 167–218, In

Preservation of Food by Ionizing Radiation,

Vol. 2, E. S. Josephson and M. S. Peterson,

eds., CRC Press, Boca Raton, Fl., 1982.

*75. Memorandum from J. Madden and L.

Bluhm, FDA, to P. Hansen, FDA, dated

January 20, 1995.

76. Tompkin, R. B., ‘‘Botulism from Meat

and Poultry Products-A Historical

Perspective,’’ Food Technology, pp. 229–236,

May, 1980.

77. Dodds, K. L. and J. W. Austin,

‘‘Clostridium botulinum,’’ pp. 288–304, in

Food Microbiology: Fundamentals and

Frontiers, M. P. Doyle, L. R. Beuchat, and T.

J. Montville, eds., ASM Press, Washington,

DC, 1997.

78. Lebepe, S., et al., ‘‘Changes in

Microflora and Other Characteristics of

Vacuum-Packaged Pork Loins Irradiated at

3.0 kGy,’’ Journal of Food Science, 55(4):918–

924, 1990.

79a. Lambert, A. D., J. P. Smith, and K. L.

Dodds, ‘‘Combined Effect of Modified

Atmosphere Packaging and Low-Dose

Irradiation on Toxin Production by

Clostridium botulinum in Fresh Pork,’’

Journal of Food Protection, 54(2):94–101,

1991.

79b. Lambert, A. D., J. P. Smith, and K. L.

Dodds, ‘‘Effect of Headspace CO2

Concentration on Toxin Production by

Clostridium botulinum in MAP, Irradiated

Fresh Pork,’’ Journal of Food Protection,

54(8):588–592, 1991.

79c. Lambert, A. D., J. P. Smith, and K. L.

Dodds, ‘‘Effect of Initial O2 and CO2 and

Low-Dose Irradiation on Toxin Production by
Federal Register / Vol. 62, No. 232 / Wednesday, December 3, 1997 / Rules and Regulations 64121

Clostridium botulinum in MAP Fresh Pork,’’

Journal of Food Protection, 54(12):939–944,

1991.

80. Niemand, J. G., et al., ‘‘Radurization of

Prime Beef Cuts,’’ Journal of Food Protection,

44:677–681, 1981.

81. Ehioba, R. M., et al., ‘‘Identification of

Microbial Isolates from Vacuum-Packaged

Ground Pork Irradiated at 1 kGy,’’ Journal of

Food Science, 53:278–282, 1988.

List of Subjects in 21 CFR Part 179

Food additives, Food labeling, Food

packaging, Radiation protection,

Reporting and record keeping

requirements, Signs and symbols.

Therefore, under the Federal Food,

Drug, and Cosmetic Act and under

authority delegated to the Commissioner

of Food and Drugs, 21 CFR part 179 is

amended as follows:

PART 179—IRRADIATION IN THE

PRODUCTION, PROCESSING AND

HANDLING OF FOOD

1. The authority citation for 21 CFR

part 179 continues to read as follows:

Authority: 21 U.S.C. 321, 342, 343, 348,

373, 374.

2. Section 179.26 is amended in the

table in paragraph (b) by adding a new

entry ‘‘8.’’ under the headings ‘‘Use’’

and ‘‘Limitations’’ to read as follows:

§ 179.26 Ionizing radiation for the

treatment of food.

* * * * *

(b) * * *

Use Limitations

* * * * * * *

8. For control of foodborne pathogens in, and extension of the shelf-life

of, refrigerated or frozen, uncooked products that are meat within the

meaning of 9 CFR 301.2(rr), meat byproducts within the meaning of

9 CFR 301.2(tt), or meat food products within the meaning of 9 CFR

301.2(uu), with or without nonfluid seasoning, that are otherwise

composed solely of intact or ground meat, meat byproducts, or both

meat and meat byproducts..

Not to exceed 4.5 kGy maximum for refrigerated products; not to exceed 7.0 kGy maximum for frozen products.

* * * * *

Dated: November 26, 1997.

Michael A. Friedman,

Lead Deputy Commissioner for the Food and

Drug Administration.

[FR Doc. 97–31740 Filed 12–2–97; 8:45 am]

BILLING CODE 4160–01–F