The Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) are two governmental agencies that regulate food safety to protect the general public from potential hazards such as chemical contamination, spoilage and food poisoning. The Food, Drug and Cosmetic Act of 1938 defines potential hazards by distinguishing between additives and naturally-occurring elements in a food item or product. This legislation, and the numerous amendments and changes that have taken place over the years, have identified potential food safety hazards that occur between the harvest and purchase of food.
Bacterial Food Hazards
Bacteria threaten food supplies, according to the FDA. Small organisms have the potential to infest food at any time during the harvesting, processing, shipping, storing and preparation processes. These hazards occur when micro-organisms such as bacteria, parasites and viruses find their way into a food product. Some of these organisms are beneficial to the ecosystem in their natural state, but may become potential hazards under certain conditions, such as when high temperatures or humidity are present. The microscopic size of these contaminants is the reason that they are considered to be a major concern, as these organisms are present in the air, in the water and even on the human body. These infective organisms are easily introduced to food crops as they grow, and will contaminate crops during harvesting and storage in silos and bulk grain bins. They are also present in food-processing facilities where human workers handle food and food-processing equipment, and possibly carry these organisms on their bodies or clothing.
According to the USDA's "Kitchen Companion: Your Safe Food Handbook," pathogenic bacteria such as salmonella, E.coli, Staphylococcus aureus and Clostridium perfringens are most often present on fruits and vegetables, while others are generally carried on human skin and contaminate food during handling and preparation. The USDA states that all pathogenic bacteria are generally removed with proper washing and cooking temperatures.
Chemical Food Hazards
Chemical food hazards can enter the food supply during growing and harvesting. Food growers often use pesticides, fertilisers and growth hormones.
Other chemical food hazards can come from things added to the food during processing, even when added according to regulatory guidelines. Sulphite is a common additive in winemaking and shrimp-processing, but excessive sulphite has a debilitating effect on people who are allergic to it. Also, metals such as copper, zinc, cadmium and lead are often introduced into food during the processing and packaging phase and can be present when food is prepared in restaurant kitchens and other food facilities. Glazing materials such as cadmium have the potential to turn acidic foods such as tomato juice and pickled vegetables into food hazards.
Physical Food Hazards
Physical debris presents a potential hazard to foods and occurs at all phases of the food supply process. Bone chips from meat processing, metal flakes from cutting tools or storage containers, human fingernails and hair and insect and rodent waste often find their way into food products. This debris causes adverse reactions in many people, including allergic reactions, choking, digestive problems, broken teeth and abrasions in the mouth and oesophagus.
The food industry works to prevent these types of items from becoming potential food safety hazards. It uses methods such as X-ray technology, stringent inspecting during food processing and packaging and pest control practices. The use of tamper-proof packaging and employee training in food-handling also help to prevent physical debris from affecting food supplies.