Metals – both beneficial and harmful – are in many foods. This is because our air, water and soil all contain metals (and elements that combine metals and nonmetals called metalloids). The levels found in food depend on many factors, including: growing conditions; industrial, manufacturing, and agricultural processes; the DNA of the food crops; and past or current environmental contamination. In addition, some metals the human body needs, such as iron, are intentionally added to certain foods, including breakfast cereals and infant formulas, to enhance their dietary benefits.
To keep the U.S. food supply among the safest in the world, the FDA monitors and tests foods and sets standards to ensure appropriate and safe levels of beneficial metals while limiting harmful metals in foods to the greatest extent practical. The FDA also monitors and regulates levels of metals in animal feed and in cosmetics. The FDA uses its authority to take action on a case-by-case basis when the level of metals in FDA regulated products is determined to be unsafe.
The properties of specific metals, the amount of intake, and a person’s age and developmental stage are all key factors that help determine how a metal affects individual health. Even metals that promote health can be harmful if exposure exceeds recommended doses. For example, iron is an essential dietary metal and although the body regulates iron absorption to help safeguard against getting too much, iron poisoning is something that can occur, usually from ingestion of too many iron supplement pills. Symptoms may include severe vomiting, diarrhea, abdominal pain, dehydration and lethargy if not treated properly.
Certain metals, such as arsenic, lead and mercury, have no established health benefit, and have been shown to lead to illness, impairment, and in high doses, death. Understanding the risk that harmful metals pose in our food supply is complicated by the fact that no single food source accounts for most people’s exposure to metals in foods. People’s exposure comes from many different foods containing these metals. Combining all of the foods we eat, even low levels of harmful metals from individual food sources, can sometimes add up to a level of concern.
The agency’s Toxic Elements Working Group (TEWG) aims to reduce exposure to toxic elements in food, cosmetics and dietary supplements. The group is made up of senior leaders and risk managers in the Center for Food Safety and Applied Nutrition (CFSAN) with experience in microbiology, toxicology, chemistry, medicine, epidemiology, policy and law. Working with scientists across the Center, the group is tackling the issues presented by metals using the following approach:
- Prioritizing metals by toxicity and prevalence – The group is looking at the presence of metals in all products CFSAN regulates and identifying the areas where the FDA can have the greatest impact on reducing exposures. The workgroup is focusing first on: lead, arsenic, cadmium, and mercury in foods, cosmetics, and dietary supplements, because high levels of exposure to those metals are likely to have the most significant impact on public health. Essential to prioritization is studying the large amount of data we have collected over the years. The FDA has been collecting data on contaminants and nutrients in foods for decades as part of its Total Diet Study. The study routinely samples products found in grocery stores from across the country, testing them for hundreds of contaminants, including these metals. These data are important because they can help us better understand how consumers are exposed to these contaminants.
- Identifying most vulnerable populations – People vulnerable to the harmful effects of metals in food include infants and children, the elderly, and consumers who may have chronic health conditions. As the agency works to reduce consumer exposure to metals through foods and other products, we are paying special attention to children because their smaller body sizes and metabolism may make them more susceptible to the harmful effects of these metals. Of particular concern is the effect these metals have on children’s neurological development.
- Determining effective ways to reduce exposure –The FDA is committed to using the best available science to inform and support policy decisions on toxic metals. FDA will consider a wide range of policies and actions to reduce exposure, ranging from requiring or encouraging industry to take steps to reduce the presence of the metals in products to educating consumers about ways they can reduce the risks posed by these metals.
More on the TEWG can be found on What FDA is Doing to Protect Consumers from Toxic Metals in Foods.
The FDA monitors levels of metals and other elements in food and food contact surfaces to inform and enforce FDA rules and guidance. The FDA tests for metals and other elements through the Total Diet Study; the FDA’s Toxic Elements in Food and Foodware; and Radionuclides in Food compliance program; and through targeted sampling assignments. Sampling assignments may be conducted in response to reports of elevated levels of toxic metals or other elements in certain foods or to focus on a specific food, food additive, or specific food group (such as foods commonly eaten by infants and toddlers).
Metals Tested for in FDA’s Total Diet Study
|Metals with Daily Intake Requirements||Metals that are Harmful to Health|
|Calcium, Chromium, Copper, Iron, Magnesium, Manganese, Molybdenum, Potassium, Sodium, Zinc||
Aluminum*, Antimony*, Arsenic, Barium*, Beryllium*, Cadmium, Lead, Mercury, Silver*, Strontium, Nickel, Thallium*, Uranium, Vanadium
*Tested in bottled drinking water only
FDA experts participate in the international standard-setting body, Codex Alimentarius Commission (Codex). The purpose of Codex is to protect the health of consumers and promote fair trade practices by adopting scientifically based standards, guidelines, and codes of practice across all areas of food safety and quality. Its work includes reviewing the scientific data concerning arsenic and other contaminant levels in foods. These international discussions can lead to recommendations for standards individual countries may adopt and codes of practice to prevent or reduce the presence of contaminants in food.