[Federal Register Volume 69, Number 246 (Thursday, December 23, 2004)]
[Rules and Regulations]
[Pages 76844-76847]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-28043]
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DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration
21 CFR Part 179
[Docket No. 2003F-0088]
Irradiation in the Production, Processing and Handling of Food
AGENCY: Food and Drug Administration, HHS.
ACTION: Final rule.
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SUMMARY: The Food and Drug Administration (FDA) is amending the food
additive regulations by establishing a new maximum permitted energy
level of x rays for treating food of 7.5 million electron volts (MeV)
provided that the x rays are generated from machine sources that use
tantalum or gold as the target material, with no change in the maximum
permitted dose levels or uses currently permitted by FDA's food
additive regulations. This action is in response to a petition filed by
Ion Beam Applications.
DATES: This rule is effective December 23, 2004. Submit written
objections and request for a hearing by January 24, 2005. See Section
VII of this document for information on the filing of objections.
ADDRESSES: You may submit written objections and requests for a
hearing, identified by Docket No. 2003F-0088, by any of the following
methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the instructions for submitting comments.
Agency Web site: http://www.fda.gov/dockets/ecomments.
Follow the instructions for submitting comments on the agency Web site.
E-mail: [email protected]. Include Docket No. 2003F-
0088 in the subject line of your e-mail message.
FAX: 301-827-6870.
Mail/Hand delivery/Courier [For paper, disk, or CD-ROM
submissions]: Division of Dockets Management (HFA-305), Food and Drug
Administration, 5630 Fishers Lane, rm. 1061, Rockville, MD 20852.
Instructions: All submissions received must include the agency name
and docket number for this rulemaking. All objections received will be
posted without change to http://www.fda.gov/ohrms/dockets/default.htm,
including any personal information provided. For detailed instructions
on submitting objections, see the ``Objections'' heading of the
SUPPLEMENTARY INFORMATION section of this document.
Docket: For access to the docket to read background documents or
comments received, go to http://www.fda.gov/ohrms/dockets/default.htm
and insert the docket number, found in brackets in the heading of this
document, into the ``Search'' box and follow the prompts and/or go to
the Division of Dockets Management, 5630 Fishers Lane, rm. 1061,
Rockville, MD 20852.
FOR FURTHER INFORMATION CONTACT: Celeste Johnston, Center for Food
Safety and Applied Nutrition (HFS-265), Food and Drug Administration,
5100 Paint Branch Pkwy., College Park, MD 20740-3835, 301-436-1282.
SUPPLEMENTARY INFORMATION:
I. Introduction
In a notice published in the Federal Register of March 13, 2003 (68
FR 12087), FDA announced that a food additive petition (FAP 3M4745) had
been filed by Ion Beam Applications (IBA), 6000 Poplar Ave., suite 426,
Memphis, TN. Since the publication of this notice, IBA has been sold to
PPM Ventures, which subsequently changed its name to Sterigenics
International, Inc., 2015 Spring Rd., suite 650, Oak Brook, IL 60523.
As a result, the rights to FAP 3M4745 have been transferred from IBA to
Sterigenics International, Inc. The petition proposed that the food
additive regulations in Sec. 179.26 Ionizing radiation for the
treatment of food (21 CFR 179.26) be amended by increasing the maximum
permitted energy level of x rays for treating food to 7.5 MeV from the
currently permitted maximum level of 5 MeV. Higher x ray energy will
result in an increased concentration of x rays in the forward direction
and increased penetration of these x rays in materials. This increased
emission efficiency (i.e., concentration of x rays produced in the
forward direction) will result in reduced treatment time for food, and
therefore, higher production rates and lower treatment costs. The
increased penetration of 7.5 MeV versus 5 MeV x rays will allow for the
irradiation of larger packages.
II. Evaluation of Safety
A source of radiation used to treat food meets the definition of a
food additive under section 201(s) of the Federal Food, Drug, and
Cosmetic Act (the act) (21 U.S.C. 321(s)). 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 data available to
FDA establishes that the additive is safe for that use. FDA's food
additive regulations in 21 CFR 170.3(i) define safe as ``a reasonable
certainty in the minds of competent scientists that the substance is
not harmful under the intended conditions of use.''
III. Evaluation of the Safety of the Petitioned Use of 7.5 MeV X Rays
A. Safety Concerns of Higher Energy X rays
The maximum energy limit of an x-ray machine is the maximum energy
of the individual x-ray photons produced by that machine. When
individual photons of x rays are absorbed by food, the absorbed energy
causes atoms to be ionized until all the energy is converted into heat
or chemical change. The amount of change in the food will depend on the
total energy absorbed (i.e., dose). Because this petition seeks only to
raise the maximum energy limit for x rays used for treating food, with
no change in the maximum doses currently permitted by Sec. 179.26, FDA
concludes that the petition presents no new chemical issue, and that
the only safety issue to be addressed is the potential for inducing
radioactivity in the food.
Food, as well as other natural materials, displays low levels of
naturally occurring radioactivity, such as that due to the presence of
potassium-40 or carbon-14. To assess the safety of increasing the
maximum energy of x rays to 7.5 MeV, the petitioner evaluated the
potential for 7.5 MeV x rays to induce additional radioactivity in
food. X rays with energies above an atom's threshold energy are capable
of ejecting neutrons or protons from the nuclei of some atoms that have
absorbed the x-ray energy. The threshold energy needed to cause the
emission of a proton is higher than 7.5 MeV; therefore, the primary
mechanism for inducing radioactivity in food by 7.5 MeV x rays will be
from the loss of a neutron. This may in some cases result in the
formation of radioactive nuclei. Radioactive nuclei are unstable and
decay to a more stable form, spontaneously emitting particles and
electromagnetic radiation in the form of gamma rays (i.e., high-energy
photons). Often, this transition can occur very rapidly, such that an
isotope produced in food from x rays will decay to a stable,
nonradioactive state before leaving the irradiation facility. However,
some radioactive isotopes could be sufficiently stable to be present in
food
[[Page 76845]]
when ingested. Radioactive atoms decay at a rate specific to their
identity and, if taken into the body, could emit ionizing energy that
would be absorbed in tissues in the body. Whether any emitted energy
would increase the risk of harm to health depends on the amount and
type of radiation absorbed by the body and the site of absorption.
Two reports in the petition provide the petitioner's primary basis
that the petitioned use of 7.5 MeV x-ray radiation is safe. One report,
from the International Atomic Energy Agency (IAEA), addresses natural
and induced radioactivity in food treated with radiation, including
high energy x rays (Ref. 1). The second report, by Gregoire et al.,
assesses the induced activities in fresh meat and in meat ash
irradiated with high-energy x rays using evidence provided by
theoretical calculations and experimental measurement (Ref. 2). As part
of its review, FDA contracted with the Department of Energy, Oak Ridge
National Laboratory (ORNL), for an independent evaluation of data in
the petition (Ref. 3).
B. Neutron-Induced Radioactivity in Food
The IAEA report provides a compilation of available data on natural
and induced radioactivity in food and investigates to what extent
increases in absorbed dose in food or increased energy levels of
radiation sources used to irradiate food could induce radioactivity in
the food. One of the scenarios considered in the report was the
potential for inducing radioactivity in food after being irradiated
with 7.5 MeV x rays (using an x-ray target of tantalum or gold) to a
dose of 30 kiloGray (kGy).\1\ The report compared possible radiation
exposure in humans from induced radioactivity in food to that from
natural radioactivity in food. A reference food model was used for this
analysis with an elemental composition similar to that of meat.\2\ The
report concluded that consuming 40 kilograms (kg) (88 pounds) per year
of reference food with an absorbed dose of 30 kGy (a dose more than six
times the maximum permitted dose level of 4.5 kGy permitted by FDA for
refrigerated meat and meat products), would result in an estimated
human radiation exposure of 1.3 x 10-3 millisieverts/year
(yr) (mSv/yr) (a dose 300 times less than the yearly dose due to
natural radioactivity from food) (Ref. 1). The calculation assumed that
the food would be eaten immediately after being irradiated. However,
the radioisotopes with the greatest probability of being produced decay
quite rapidly. Therefore, because of radioactive decay, any
radioactivity in the treated food, which would normally be consumed
more than 24 hours after treatment, would actually be significantly
less at the time of consumption.
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\1\Thirty kGy is close to a sterilizing dose. Foods, generally,
would not be irradiated at such a high dose.
\2\The concentrations of elements in the reference food were
chosen to be reasonably close to those of meat because, compared to
other foods, meat is likely to be the food that receives the highest
doses and that is consumed in the largest quantities. Although the
concentrations of trace elements in foods can vary significantly,
the difference in the radiation exposure to humans from consumption
of one irradiated food and another food due to these variances would
be insignificant.
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The report by Gregoire et al. provided theoretical estimates and
experimental results of the radiological implications of irradiating
meat with higher energy x rays. Induced activities in meat irradiated
at 15 kGy with 7.5 MeV x rays and a resultant human exposure to
radiation were calculated. Based on the most abundant isotopes produced
in meat by neutron capture reactions at thresholds below 7.5 MeV, and
assuming a person consumes 40 kg of meat per year and a 24-hour delay
between irradiation and consumption, the corresponding dose to humans
was calculated to be 0.2 x 10-3 mSv/yr.
Theoretical estimates of induced activity can be more reliable than
direct measurements, especially for low levels of activity. However, to
check the validity of the theoretical estimates, Gregoire et al.
compared their predictions with experimental data. Experimental results
from a 1991 study by Wakeford and Blackburn were discussed. This study
investigated the irradiation of codfish, rice, and a macerated meat
product with x rays produced by an electron linear accelerator that
generated electrons at energies up to 12 MeV and predominately at 8 MeV
(Ref. 4). These foods received radiation doses ranging from 8.8 to 14
kGy. Induced activities in the foods were reported to be approximately
the same as natural background levels, and dropped quickly. The report
also summarized the results from another study in which induced
activities in fresh meat and in meat ash were measured after being
irradiated with x rays generated at 7.3 MeV and 8.1 MeV at doses of 15
kGy and 8.6 kGy, respectively. Based on the measured activity from the
two experiments and assuming a consumption of 40 kg/y of irradiated
meat and a 24-hour delay time between irradiation and consumption, the
total annual dose from meat due to treatment with higher energy x rays
was determined to be 0.24 to 0.29 x 10-3 mSv/yr, a dose
about 1,500 times lower than the 0.39 mSv received per year from
consumption of food due to naturally occurring radionuclides (Ref. 3).
Because most meat would be consumed more than 24 hours after treatment,
the annual dose from the irradiated meat would be far less than the
dose indicated from these experiments.
ORNL evaluated the information in the IAEA report. ORNL estimated
induced activities in beef irradiated to 15 kGy with 7.5 MeV x rays and
the resultant dose from consumption of the treated food (Ref. 3). ORNL
used the elemental composition of beef for their analysis because its
composition is similar both to that of the reference food used in the
IAEA report and to food in general. From this information, ORNL
determined induced radioactivity in beef and used this to estimate a
potential radiation dose to humans from consumption of the food. The
annual effective dose based on consumption of 40 kg/yr of beef was
calculated to be 0.4 x 10-3 mSv, which is approximately
1,000 times less than the annual effective dose from consumption of
foods due to naturally occurring radioactivity, and is consistent with
the results from both the IAEA report and the Gregoire et al. report.
In addition to beef, ORNL also calculated the effective annual dose
from consumption of pork, poultry, and eggs treated with 7.5 MeV x rays
and an absorbed dose of 15 kGy, ORNL determined that based on the
average quantity of beef, pork, poultry, and eggs consumed in a year,
the total effective annual human exposure from consumption of these
irradiated foods would be 1.0 x 10-3 mSv/yr, which is about
400 times less than the 0.39 mSv/yr that people receive due to natural
radioactivity in food. It is also important to note that this estimated
exposure is highly conservative because it assumes the following: (1)
That all of the beef, pork, poultry, and eggs that a person consumes in
a year has been irradiated, (2) that these foods are consumed within 24
hours after irradiation, and, (3) that such foods would be treated with
an average dose of 15 kGy, which is significantly higher than both the
currently maximum permitted dose for these foods as well as doses that
would be practical to apply to foods in commerce.
The results discussed previously considered potential radiation
exposure for humans from consumption of various foods irradiated with
high energy x rays. Although foods other than those that were studied
may be irradiated with 7.5 MeV x rays, the
[[Page 76846]]
compositions of the foods that were considered are representative of
foods in general. Even at absorbed doses that are higher than those
normally used in practice, the results clearly show that any
radioactivity that may be induced in any food treated with 7.5 MeV x
rays will be trivially low and that any potential human exposure due to
consumption of irradiated food will be inconsequential compared to that
from radionuclides that are present naturally in food.
C. The Need to Limit the X-Ray Target Material
Neutrons emitted from the x-ray target in the x-ray generator can
also enter food and induce radioactivity. Therefore, FDA considered
whether there is a need to specify or limit the x-ray target material
to minimize neutron production from this source. Materials with
photoneutron threshold energies below 7.5 MeV can produce
photoneutrons, which could also be captured in the foods being
irradiated. The petitioner has proposed the use of tantalum and gold as
x-ray target materials. The x-ray energy levels needed to eject a
neutron from the two common isotopes of tantalum (Ta-180 and Ta-181)
are 6.6 and 7.6 MeV, respectively, but the neutron production from 7.5
MeV x rays is insignificant, and considerably less than from tungsten,
a common x-ray target material (Refs. 1 and 3). Gold also does not
produce significant numbers of neutrons when impinged with 7.5 MeV x
rays (Ref. 1). Therefore, FDA concludes that tantalum and gold are
acceptable x-ray target materials for the proposed use and is
specifying these two x-ray target materials as a condition of safe use
for machine sources of 7.5 MeV x rays.
IV. Conclusion of Safety
FDA has evaluated the data submitted in the petition and other
relevant material and concludes that any added radioactivity in food
from the use of 7.5 MeV x rays will be trivial compared to that from
radionuclides that are present naturally in food. Therefore, the agency
concludes that the proposed use of 7.5 MeV x rays for treating food is
safe and that the conditions listed in Sec. 179.26 should be amended
as set forth in this document.
In accordance with Sec. 171.1(h) (21 CFR 171.1(h)), the petition
and the documents that FDA considered and relied upon in reaching the
agency's decision to approve the petition are available for inspection
at the Center for Food Safety and Applied Nutrition by appointment with
the information contact person (see FOR FURTHER INFORMATION CONTACT).
As provided in Sec. 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.
V. Environmental Impact
The agency has previously considered the environmental effects of
this rule as announced in the notice of filing for FAP 3M4745 (68 FR
12087). No new information or comments have been received that would
affect the agency's previous determination that there is no significant
impact on the human environment and that an environmental impact
statement is not required.
VI. Paperwork Reduction Act of 1995
This final rule contains no collection of information. Therefore,
clearance by the Office of Management and Budget under the Paperwork
Reduction Act of 1995 is not required.
VII. Objections
Any person who will be adversely affected by this regulation may
file with the Division of Dockets Management (see ADDRESSES) written or
electronic objections by (see DATES). 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 are to be
submitted and are to 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 Division of Dockets
Management between 9 a.m. and 4 p.m., Monday through Friday.
VIII. References
The following references have been placed on display in the
Division of Dockets Management (see ADDRESSES) and may be seen by
interested persons between 9 a.m. and 4 p.m., Monday through Friday.
1. International Atomic Energy Agency, ``Natural and Induced
Radioactivity in Food,'' IAEA-TECDOC-1287, Food and Environmental
Protection Section, IAEA, Vienna, 2002.
2. Gregoire, O., Cleland, M. L., Wakeford, Mittendorfer, et al.,
``Radiological Safety of Food Irradiation With High Energy X-Rays:
Theoretical Expectations and Experimental Evidence,'' 2002.
3. Easterly, C. E., Eckerman, K. F., Ross, R. H., et al.,
``Assessment of Petition to Increase the Maximum X-Ray Energy to 7.5
MeV from the Value of 5.0 MeV for the Treatment of Food by Ionizing
Radiation,'' ORNL-2003-1, Oak Ridge National Laboratory, Life Sciences
Division, 2003.
4. Wakeford, C. A., Blackburn R., and Swallow, A. J., ``Induction
and Detection of Radioactivity in Foodstuffs Irradiated With 10 MeV
Electrons and X-Rays,'' Radiation Physics and Chemistry, vol. 38, No.
1, pp. 29-38, 1991.
List of Subjects in 21 CFR Part 179
Food additives, Food labeling, Food packaging, Radiation
protection, Reporting and recordkeeping requirements, Signs and
symbols.
0
Therefore, under the Federal Food, Drug, and Cosmetic Act and under
authority delegated to the Commissioner of Food and Drugs and
redelegated to the Director, Center for Food Safety and Applied
Nutrition, 21 CFR part 179 is amended as follows:
PART 179--IRRADIATION IN THE PRODUCTION, PROCESSING AND HANDLING OF
FOOD
0
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.
0
2. Section 179.26 is amended by revising paragraph (a)(3) and by adding
paragraph (a)(4) to read as follows:
Sec. 179.26 Ionizing radiation for the treatment of food.
* * * * *
(a) * * *
(3) X rays generated from machine sources at energies not to exceed
5 million electron volts (MeV), except as permitted by paragraph (a)(4)
of this section.
(4) X rays generated from machine sources using tantalum or gold as
the target material and using energies not to exceed 7.5 (MeV).
* * * * *
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Dated: December 14, 2004.
Leslye M. Fraser,
Director, Office of Regulations and Policy, Center for Food Safety and
Applied Nutrition.
[FR Doc. 04-28043 Filed 12-22-04; 8:45 am]
BILLING CODE 4160-01-S