Food irradiation is a common practice that is frequently misunderstood. Not only has the process of exposing food products to ionizing radiation, including X-Rays or electron beams, been heavily researched and utilized safely for over a century, it is a process that has proven benefits for the health of human beings.
The history of food irradiation.
The process of irradiating food began as early as 1905 when patents were issued in the U.S. and Great Britain to use ionizing radiation to kill bacteria found in foods. After World War II, research was conducted by the U.S. Army to verify the safety and efficacy of the irradiation process for meat, dairy products, fruits, and vegetables. Food irradiation has been controlled by the Food and Drug Administration since 1958 and recognized by the United Nations since 1964, when the first meeting of the Joint Expert Committee on Food Irradiation took place. It was determined by this committee in 1980 that “irradiation of foods up to the dose of 10 kiloGrays introduces no special nutritional or microbiological problems,” and the use of irradiation in the U.S. food supply was expanded by the FDA in 1986. In addition to the FDA and the UN, irradiation has been endorsed by the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the U.S. Department of Agriculture (USDA).
Why irradiate food?
There are several important reasons to irradiate food which ultimately benefit humans.
Prevention of Food borne Illness – Nobody likes having food poisoning. Food irradiation eliminates bacteria and molds like Salmonella and Escherichia coli (E. coli) which can spoil food and cause serious foodborne illnesses.
Sterilization – Irradiated foods can be used to sterilize foods which do not require refrigeration. These can be used in hospital settings for individuals with compromised immune systems or those undergoing chemotherapy. A variety of household and consumable products are also irradiated for sterilization purposes, including Band-Aids, cotton balls, medical products like surgical gloves, and even cosmetics.
Preservation – Have you ever wondered why spices have such a long shelf life, or why that bag of potatoes you bought last week is still sprout free? The answer is food irradiation. Food irradiation can extend the shelf life of certain foods by destroying organisms that cause spoilage and early sprouting.
Pest-Control – Irradiation helps control invasive insects that live in or on imported fruits and vegetables by killing or sterilizing them to prevent new bugs from infecting U.S. crops. This method is also safer than certain pest-control practices which have the potential to harm the produce through the use of toxic chemicals.
Of course, the benefits to irradiating food do not diminish the need for safe food handling practices by growers, processors, and consumers. All food should be stored, handled, and cooked appropriately. If safe handling practices are not followed, disease-causing organisms can still contaminate food and illness can occur.
It also does not completely remove all food dangers. For example, food irradiation can slow fruits and vegetables from aging, but it does not stop them. It also does not eliminate dangerous toxins that are already in food, such as Clostridium botulinum, a common bacterium which produces a toxin that causes botulism.
What kind of foods are irradiated?
In the United States, the FDA has approved a variety of foods to undergo irradiation, including:
Beef and Pork
Lobster, Shrimp, and Crab
Fruits and Vegetables
Lettuce and Spinach
Spices and Seasonings
The international symbol for irradiation is called the Radura. This green symbol is required to be present on food packaging of irradiated food alongside the statements “Treated with radiation” or “Treated by irradiation.” According to the FDA, bulk foods like fruits and vegetables must be individually labelled with this symbol, however it is not required for individual ingredients in multi-ingredient foods, such as spices, to be labelled. If this symbol is present, this also indicates that the food is not classified as organic no matter how it was grown or produced.
How is food irradiated?
The overall process is simple. Three different kinds of radiation are approved for use: Gamma rays, electron beams, or x-rays. Packaged or bulk food pass through a radiation beam in a radiation chamber on a conveyor belt. The ionizing radiation breaks the chemical bonds into the bacteria or mold cells, which kills or damages the pathogens enough that they cannot multiply. This process does not affect the taste or smell of the food being irradiated.
This process also does not bring food into contact with radioactive materials, nor does it make food radioactive. Irradiated food does not expose those who eat it to radiation.
Are there risks to eating irradiated food?
Eating irradiated food is not harmful and there are no radiation-related risks. In fact, irradiating foods increases the availability of healthy and nutritious food supplies on a global scale. The chemical changes to food caused by irradiation are comparable to the changes food undergoes when cooked or canned.
Safe and beneficial.
Exposing food products to ionizing radiation is a safe, heavily researched process endorsed by governing agencies around the world. It is responsible for controlling invasive insects, destroying harmful bacteria that can cause food borne illnesses, and increases the shelf-life of certain foods which allows for more widespread access to healthy, nutritious food. This process also poses no radiation-risks to the public.
The ALARA principle is a relatively simple safety protocol designed to limit ionizing radiation exposure to workers from external sources.
This principle was established by the National Council on Radiation Protection and Measurements (NCRP) in 1954 in response to the atomic bombings of Hiroshima and Nagasaki and the increased interest in nuclear energy and weaponry post-WWII. The philosophy has been refined over the years by different regulatory agencies such as the Atomic Energy Commission (AEC) and Nuclear Regulatory Commission (NRC) as more knowledge about radiation and its effects on living tissue has come to light. In its current form, ALARA stands for “as low as reasonably achievable” and is considered the gold standard for radiation protection.
ALARA is based on the idea that any amount of radiation exposure, big or small, can increase negative health effects, such as cancer, for an individual. It is also based on the principle that the probability of occurrence of negative effects of exposure increases with cumulative lifetime dose. As such, the ALARA principle is considered a regulatory requirement for all radiation programs licensed with the NRC and any activity that involves the use of radiation or radioactive materials.
To successfully implement ALARA principles in your radiation safety program, “it is important that every reasonable effort be made to maintain exposures to radiation as far below the dose limits in this part as is practical consistent with the purpose for which the licensed activity is undertaken, taking into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, and other societal and socioeconomic considerations, and in relation to utilization of nuclear energy and licensed materials in the public interest.” (10 CFR 20.1003)
Time, Distance, and Shielding
There are three factors to the ALARA philosophy which, when executed correctly, can reduce and even prevent unnecessary exposure: time, distance, and shielding.
Limit the amount of time spent near a radiation source. If you must work near a radioactive source, you should work as quickly as possible and then leave the area to avoid spending more time around the source than necessary.
Increase the distance between yourself and a radiation dose. The farther away you are, the lower the dose you will receive. In many cases, the dose rate decreases as the inverse square of the distance – when the distance is doubled, the dose rate goes down by a factor of four.
Put a barrier between you and the radiation source. The type of barrier will depend on what kind of radiation source is being emitted but should be made of a material that absorbs radiation such as lead, concrete, or water. This can also include PPE such as thyroid shields and lead vests.
The ALARA principle has successfully limited exposures to workers—and patients undergoing medical procedures involving radiation—for several decades. Adhering to this principle as well as your state’s radiation safety regulations will result in keeping workers healthy and protected.
Visit our website for more information on how Versant Physics’ board-certified health physicists, medical physicists, and radiation safety officers can help you implement safe practices in your radiation safety program.
We are often asked questions about applying for or changing licenses to possess and use radioactive materials. There are many different types of licenses; choosing amongst them can be confusing. In this post, we will discuss four common types.
With some exceptions, approval by a regulatory agency (U.S. Nuclear Regulatory Commission or equivalent state agency), in the form of a license, is required to use and/or dispose of radioactive materials.
The type of license authorizing the purchase, possession, use, and disposal of radioactive materials is based on several factors:
Type, form and quantity of radioactive materials requested
Experience of the proposed licensee with managing the use of radioactive materials
Types of licenses include, but are not limited to:
Limited scope specific academic and research and development
Limited scope specific medical use
Broad scope specific
Broad scope specific medical use
In this post, we will discuss the regulations under which the U.S. Nuclear Regulatory Commission (NRC) issues two common types of licenses: (i) limited scope specific and (ii) broad scope specific. Some states, called Agreement States, have the authority under NRC regulations to issue licenses. Their regulations are equivalent to NRC regulations.
1. Limited Scope Licenses
These licenses are issued to applicants subject the following limitations:
Specified chemical and physical form(s)
Radiation Safety Officer (RSO)
Location(s) of use
TheRSO’s training and experience should be applicable to and generally consistent with the types and quantities of licensed materials listed on the license. Authorized users (AUs) must have adequate training and experience with the types and quantities they intend to use (NUREG 1556, Vol. 7, Rev. 1). The applicant must submit to the regulatory agency for review and approval the specific training and experience of each proposed user and the facilities and equipment available to support each proposed use.
If the licensee wishes to change any of these limitations or add or remove an Authorized User (AU), permission must be sought from the issuing regulatory agency to amend the license.
Medical Licenses – general comments
Licensing for the use of radioactive materials to diagnose and treat human disease is subject to more complex regulations than the academic and research and development licenses described above. A wide variety of radionuclides and physical and chemical forms are used for a multitude of purposes in human medicine. Consequently, AUs and the RSO must meet specific and extensive training and experience criteria focusing on the type, form, and quantity to be used as well as the intent of the use (diagnosis vs. treatment).
radiation safety commensurate with use of radioactive materials;
administration of a radiation dose or dosage and how it is prescribed;
direction of individuals under the AU’s supervision in the preparation of radioactive materials for medical use and in the medical use of radioactive materials; and
preparation of a written directive, if required.
To be named as an AU on a medical license, the individual must satisfy one or more of the requirements outlined in Subparts D, E, F, G or H of 10 CFR 35. In general, this requirement can be met by:
being board certified in a specialty medical discipline appropriate to the intended use that is recognized by the Commission or Agreement State; or
being named as an AU on another license issued by the Commission or Agreement State for the same or similar type, form, and quantity of radioactive materials in question; or
having completed training and experience as specified in the regulations.
The RSO on a medical license must satisfy the training and experience requirements outlined in 10 CFR 35.50:
be certified by a specialty board whose certification process has been recognized by the Commission or an Agreement State; or
have completed a structured educational program as outline in 10 CFR 35.50(b); or
be a medical physicist who is certified by a specialty board recognized by the Commission or an Agreement State, has experience with the radiation safety aspects of similar types of radioactive materials for which the licensee seeks approval and has training in the radiation safety, regulatory issues, and emergency procedures for the types of use for which a licensee seeks approval; or
be a medical AU, authorized medical physicist, or authorized nuclear pharmacist identified on a Commission or an Agreement State license, a permit issued by a Commission master material licensee, a permit issued by a Commission or an Agreement State licensee of broad scope, or a permit issued by a Commission master material license broad scope permittee, has experience with the radiation safety aspects of similar types of use of byproduct material for which the licensee seeks the approval and Is an authorized user, authorized medical physicist, or authorized nuclear pharmacist identified on a Commission or an Agreement State license, a permit issued by a Commission master material licensee, a permit issued by a Commission or an Agreement State licensee of broad scope, or a permit issued by a Commission master material license broad scope permittee, has experience with the radiation safety aspects of similar types of use of byproduct material for which the licensee seeks the approval.
2. Limited Scope Specific Medical Licenses
A specific license of limited scope may be issued to private or group medical practices and to medical institutions. Each type, form, quantity and use and condition of use of radioactive materials as well as the RSO and AU(s) are named on the license (NUREG 1556 Vol. 9, Rev. 3). These licenses may also be issued to an entity requesting authorization to perform mobile medical services and certain non-medical activities such as self-shielded blood irradiators. Changes to any of these specifications or conditions must be requested and approved by amendment.
Research Involving Human Subjects
“Medical use” of radioactive materials includes administration to human research subjects. A license condition authorizing such research is not required if the research is conducted, funded, supported or regulated by a Federal Agency that has implemented the Federal Policy for the Protection of Human Subjects. Otherwise, the licensee must apply for and receive an amendment before conducting such research. In all cases, licensees must obtain informed consent from the human subjects and prior review and approval by an Institutional Review Board. All research involving human subjects must be conducted only with the radioactive materials listed in the license and for the uses authorized in the license (NUREG 1556, Vol. 9, Rev. 3).
Research involving human subjects may be conducted under either limited scope or broad scope specific licenses.
3. Broad Scope Specific Licenses
Broad scope specific licenses generally authorize possession and use of a wide range of radioactive materials. Because regulatory agencies grant significant decision-making authority to broad scope licensees through the license, a broad scope license is not normally issued to a new licensee. An applicant for a broad scope license typically has several years of experience operating under a limited scope license and a good regulatory performance history (NUREG 1556 Vol. 11, Rev. 1). Changes to the radiation safety program approved via in-house review and approval by the RSO and/or RSC (see below) do not appear on the license but are subject to review by regulatory agencies during routine inspections.
Title 10 of the Code of Federal Regulations (10 CFR) Part 33, “Specific Domestic Licenses of Broad Scope for Byproduct Material,” provides for three distinct categories of broad scope licenses (i.e., Type A, Type B, and Type C), which are defined in 10 CFR 33.11, “Types of Specific Licenses of Broad Scope.”
Type A licenses of broad scope are typically the largest licensed programs and encompass a broad range of uses. Licensees use a Radiation Safety Committee (RSC), radiation safety officer (RSO), and criteria developed and submitted by the licensee and approved by the NRC during the licensing process to review and approve all uses and users under the license.
An applicant for a Type A broad scope license must establish administrative controls and provisions related to organization and management, procedures, record keeping, material control, and accounting and management review necessary to ensure safe operations, including:
establishment of an RSC
appointment of a qualified RSO
establishment of appropriate administrative procedures to ensure the following:
— control of procurement and use of byproduct material
— completion of safety evaluations of proposed uses that take into consideration adequacy of facilities and equipment, training and experience of the user, and operating and handling procedures
— review, approval, and recording by the RSC of safety evaluations of proposed uses
use of byproduct material only by, or under the direct supervision of, individuals approved by the licensee’s RSC
Because these controls and provisions have been established, the applicant may approve in-house, without requesting amendment:
location of use within the confines of the physical location(s) listed on the license
changes in use of radioactive materials so long as the use is consistent with the license conditions and appropriate safety evaluations have been performed, documented, and approved by the RSC
The requirements for issuance of a Type A broad scope license are described in 10 CFR 33.13, “Requirements for the Issuance of a Type A Specific License of Broad Scope.”
Type B broad scope licensed programs are normally smaller and less diverse than Type A broad scope programs. Type B broad scope licensees use an RSO and criteria developed and submitted by the licensee and approved by the NRC during the licensing process to review and approve all uses and users under the license. Because the RSO reviews and approves all uses and users under the license, rather than a full RSC, as established for Type A broad scope programs, the types and quantities of byproduct material authorized by the Type B broad scope license are limited to those described in 10 CFR 33.11(b) and 10 CFR 33.100, “Schedule A,” Column I. Generally, the scope of authorization for Type B licenses is limited to the experience and knowledge of the RSO.
Changes to the type, form and quantity of radioactive materials may have to be approved by the regulatory agency by amendment, depending on the specific provisions of the license.
The requirements for issuance of a Type B broad scope license are described in 10 CFR 33.14, “Requirements for the Issuance of a Type B Specific License of Broad Scope.”
Type C broad scope licensed programs typically are issued to institutions that do not require significant quantities of radioactive material but need the flexibility to possess a variety of different radioactive materials. Users of licensed material under these programs are approved by the licensee based on training and experience criteria described in 10 CFR 33.15(b). The types and quantities of byproduct material authorized by the Type C broad scope license are limited to those described in 10 CFR 33.11(c) and 10 CFR 33.100, Schedule A, Column II, again, considering the unity rule.
While 10 CFR 33.15 does not require Type C broad scope licensees to appoint an RSO, the licensee must establish administrative controls and provisions related to procurement of byproduct material, procedures, record keeping, material control and accounting, and management review to ensure safe operations. This should include the appointment of someone responsible for the day-to-day operation of the radiation safety program, such as an RSO.
Changes to the type, form and quantity of radioactive materials may have to be approved by the regulatory agency by amendment, depending on the specific provisions of the license.
The requirements for issuance of a Type C broad scope license are described in 10 CFR 33.15, “Requirements for the Issuance of a Type C Specific License of Broad Scope.”
4. Broad Scope Medical Licenses
The NRC issues specific licenses of broad scope for medical use (i.e., licenses authorizing multiple quantities and types of byproduct material for medical use under 10 CFR Part 35, as well as other uses) to institutions that (i) have experience successfully operating under a specific license of limited scope and (ii) are engaged in medical research and routine diagnostic and therapeutic uses of byproduct material (NUREG 1556, Vol. 9, Rev. 3). Typically, these are large medical centers/teaching hospitals that have a need to administer or use a wide variety of radionuclides and/or radiopharmaceuticals for diagnosis and therapy. Because these institutions have complex programs, the authority to approve changes in-house makes the program flexible and nimble.
AUs and the RSO on a broad scope medical license must meet the same criteria for training and experience as for a limited scope medical license discussed above.
A radiation safety officer is an individual responsible for radiation safety in a Nuclear Regulatory Commission (NRC) or Agreement State licensed program. They ensure that any activity involving radiation and radioactive materials is conducted safely to prohibit unnecessary exposure and that all licensed activities are conducted in compliance with both license and regulation requirements. Their responsibilities are varied and extensive, however, an RSO can generally expect to conduct reviews of occupational exposures, surveys and program audits, and lead radiation safety training sessions for authorized users, workers, and ancillary personnel. They are also in charge of spill response and contamination protocols, radioactive material transportation, storage, and disposal, and enforcing the ALARA (As Low as Reasonably Achievable) principle.
RSOs are frequently found in medical facilities that intentionally administer radioactive materials to patients in the form of X-ray and fluoroscopy procedures, radiopharmaceuticals (bone scan, stress test, PET/CT, etc), and radiation therapy. To perform these procedures, medical facilities are required to obtain a permit or license, either issued by the NRC or Agreement State, which an RSO must be listed on.
But is an RSO needed for non-medical facilities as well?
In short, yes. Having an RSO on your team is not only beneficial for the overall safety of your clients and staff but is also a requirement of any licensed radiation safety program. We have outlined five reasons that will help you determine if your facility needs an RSO.
1. Your facility houses or utilizes radioactive materials, radiation-producing machines, and/or non-ionizing radiation sources such as lasers.
Specific regulations vary from state to state, however, if your facility utilizes any kind of ionizing or non-ionizing radiation source, you need a radiation safety program, and someone specifically trained to manage it.
In addition to overseeing the radiation safety program and all that entails, the RSO will keep an inventory of all material and machines located in your organization, ensure proper labeling, maintain current machine registrations, and ensure appropriate calibration and testing are performed regularly.
2. You need a highly trained individual who is well-versed in the U.S. NRC or state specific regulations that govern radiation safety and medical use of radioactive materials.
An RSO is properly trained on principles and practices of radiation protection, radiation measurement and monitoring, the biological effects of radiation, and more.
As part of their training, they are also familiar with the extensive regulations laid out by the U.S. Nuclear Regulatory Commission (NRC) or Agreement States. It is their duty to navigate these regulations for your organization to ensure compliance, and to keep on top of any updates that may impact your organization or its employees.
3. You need someone to enforce radiation policies and procedures.
An RSO is granted the authority by management to enforce policies and procedures regarding radiation safety and regulatory compliance established in an organization’s radiation protection program or license. With all that is required of a safe, successful radiation protection program, you can rely on the RSO to make sure everything is in order and the rules are being followed by all participants.
4. You want to identify problems and implement corrective actions quickly.
Of course, accidents happen. Whether due to human error or technical malfunction, they are unavoidable. While we are all familiar with the devastating effects of radiation-related accidents, including those which occurred in the wake of nuclear accidents at Three Mile Island and Fukushima, these types of accidents are not likely to occur in your organization’s day-to-day activities. However, issues such as missing signs, incorrect labels, faulty shielding, or improperly calibrated instruments can not only cost your organization big fines but can pose direct health risks to you and your staff if left unchecked.
A designated RSO not only takes charge and initiates corrective actions during an emergency, but they are also responsible for investigating incidents and finding solutions to ensure such issues do not occur again. They are often the link between management and operations, alerting them to any problems that exist, and continually update and revise the policies laid out in their radiation safety program. They also perform regular safety training and program audits which are excellent ways to identify problem areas and terminate unsafe operations before they become a problem.
5. You want to protect your personnel from occupational radiation exposure risks.
Medical personnel are not the only ones at risk of occupational radiation exposure. Anyone who regularly uses or operates radiation-producing machinery, including researchers, manufacturers, and salespeople, can be exposed. If not properly controlled and monitored, these exposures can cause damage to the cells and genetic material and lead to serious health problems such as cataracts, temporary or permanent sterility, and cancer.
Although direct supervision of individuals using ionizing radiation is not typically a role of the RSO, the RSO is responsible for ensuring all authorized users and ancillary workers are properly trained in basic radiation safety and enforce control measures, such as shielding and personal protective equipment (PPE).
An RSO will also likely suggest a personnel monitoring program that assigns dosimeters to your staff and monitors their received radiation dose as well. In addition to advising on who and when individuals should be monitored, they will regularly monitor doses, manage declared pregnancies, and provide compliance reports.
A properly trained individual, whether they are a licensed medical professional or not, can be added to a license as the RSO if they have successfully completed all the education and experience requirements of the current regulations and agree to be responsible for implementing the radiation safety program. Depending on their other professional responsibilities, they can serve as full or part-time. An RSO should also have excellent management and record-keeping skills and be comfortable with interacting with regulatory agencies.
Due to the extensive training and knowledge required for this role, many organizations choose to outsource this work. Versant Physics offers RSO and Regulatory support for traditional medical facilities such as hospitals and clinics, universities, small businesses, medical equipment manufacturers, and more. Whether you are looking for a consultant to assist on minor aspects of your program, on-site personnel to perform a program audit or survey, or you need help managing your personnel dosimetry program, our experienced, knowledgeable medical and health physicists, qualified experts, and support specialists can help.
THE PERMISSION SYSTEM FOR INVENTORY TRACKING, MACHINE MANAGEMENT & EQUIPMENT CATALOG MODULES
Each permit has a dedicated profile of information that includes authorized personnel, radioactive material, machines, and devices. Permit conditions, completed audits, and forms are also found on this profile.
Authorized Condition Database
Create and view authorized conditions included on permits. Previously created authorized conditions are listed with their code, category, and description.
Information specified on a permit not only serves as a record of that permit, but also controls what can be added to other modules. The location, owner and type of radioactive materials, machines, and equipment can be enforced by permits.
Perform permit audits, mail the results to relevant personnel, and track responses to non-compliances.