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U.S. Department of Health and Human Services


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List of Terms: R

Return to Comprehensive List of Terms


Did You Know?

Photo of Frederick McKinley Jones
Photo © Copyright H. mitchell Courtesy of Lemelson-MIT Awards Program
Frederick McKinley Jones


Frederick McKinley Jones, an African-American from Cincinnati, OH, was the first person to invent a practical, mechanical refrigeration system for trucks and railroad cars, which eliminated the risk of food spoilage during long-distance shipping trips. Jones was issued the patent on July 12, 1940.


> Recall A voluntary action of removing a product from retail or distribution. The action is conducted by a manufacturer or distributor to protect the public from products that may cause health problems or possible death.

Food Safety Implication: The purpose of a recall is to remove food from commerce when there is reason to believe it may be injurious to health or unfit for human consumption or misbranded (false or misleading labeling and/or packaging). When there is an outbreak of foodborne illness, a recall of a food may be implemented to prevent further exposure or spread of the infection.

The Food Safety and Inspection Service (FSIS) of the U.S. Department of Agriculture (USDA) inspects and regulates meat, poultry, and processed eggs. All other food products fall under the regulatory authority of the Food and Drug Administration (FDA). If the source of the outbreak is a specific food being distributed, FDA or FSIS (depending on which agency has jurisdiction over the food) can request a firm to recall the food.

Most product recalls regulated by FDA or FSIS are carried out voluntarily by the manufacturer or distributor. On the other hand, if a company does not comply with a requested recall, the FDA can seek a court order authorizing the Federal Government to seize the product. FSIS has the legal authority to detain and/or seize meat and poultry products in commerce when there is reason to believe they are hazardous to public health or if other consumer protection requirements are not met.


> Refrigeration The process of chilling (or freezing) food for preservation.

Food Safety Implication: Prompt refrigeration slows or stops bacterial growth. This, in turn, helps prevent food spoilage and foodborne illness.

Unlike other foodborne bacteria, Yersinia enterocolitica and Listeria can grow at refrigerator temperatures. These bacteria can be killed by cooking foods to safe internal temperatures.


> Ribonucleic Acid (RNA) A complex compound of high molecular weight that functions in transcription and translation in cellular protein synthesis. RNA differs from DNA by the substitution of uridine for thymine. RNA serves as a carrier of genetic codes in some viruses.

Food Safety Implication: Some viruses have genetic information encoded on RNA, rather than on DNA molecules. The Caliciviruses are a group of RNA viruses that can cause foodborne illness. One of the techniques for detecting and identifying Caliciviruses is to use a reverse transcriptase enzyme to form a DNA molecule from the isolated viral RNA, and then use polymerase chain reaction methods to make many copies of this DNA molecule and use them to identify the virus.


> Risk Assessment A process of estimating the severity and likelihood of harm to human health or the environment occurring from exposure to a substance or activity that, under plausible circumstances, can cause harm to human health or to the environment.

Risk assessment includes estimates of variability of uncertainty and is based on the best reasonably obtainable and sound scientific knowledge available. Assessing and managing risks associated with food safety is the core of the Food and Drug Administration's public health protection duties.

Food Safety Implication: Food can never be proven to be entirely safe. It can only be proven to be safe or hazardous to some degree under certain conditions. Assessing risks helps government agencies and manufacturers reduce potential hazards from foods.

How It Works: Risk assessment involves taking scientific knowledge in quantitative terms and applying it to a computer model. "What if" questions are applied, such as "How many people would get sick from eating crops that were fertilized with unprocessed manure?" The results to these questions can be applied to risk-management strategies. Risk management is the process of weighing policy alternatives as a result of risk assessment and selecting and implementing appropriate control options. For example, it's the act of washing your hands to prevent foodborne illness or wearing a helmet to avoid the risk of a head injury.

Understanding Risk Assessment:

Risk assessment analyzes the following:

  • What can go wrong?
  • How likely is it to happen?
  • How severe are the consequences?
  • What is the magnitude of the outcome should the unwanted event occur?

For instance, compare the risk of putting a test tube of harmful bacteria, such as E. coli O157:H7, in a glass of water and drinking it versus putting the same amount of the bacteria in a swimming pool and swallowing some water while swimming. The chance of getting sick is much greater from drinking the glass of water because of the higher concentration of bacteria in the glass.

Also, each time someone doesn't wash his or her hands before preparing food, he or she is deciding that the 20 seconds needed to perform this task is too much time to "waste" to prevent a foodborne illness. This person may not know the risk involved or believes the risk is very low.