Putting Arsenic In Food Into Perspective: What You Need To Know 

The presence of heavy metals in food is not new. Arsenic, like most heavy metals, is naturally occurring and can be detected at trace levels in food. Heavy metals are found in soil, water, and air; they are not added to food. While arsenic may be detected in some plant-based foods, its presence remains extremely low. Still, overexposure to arsenic can cause adverse health effects.   

 The U.S. Food and Drug Administration (FDA) is the lead U.S. Agency for protecting the public from overexposure to arsenic in food. Initiatives like FDA’s Closer To Zero program are actively working to reduce exposure to arsenic and other heavy metals for all ages. 

 To reduce exposure to arsenic and other heavy metals through food as well as promote good health and nutrition, consumers should continue to eat a variety of nutrient-dense foods across and within the main food groups of vegetables, fruits, grains, dairy, and proteins.  

What Is Arsenic?

Arsenic is a naturally occurring element found in soil, water, and air. It can also be released into the air by industrial processes, tobacco smoke, burning of fossil fuels, and volcanic eruptions.   

Arsenic compounds fall into three categories: 

• Organic: Combined with carbon and other elements; less toxic, found in foods like rice and seafood. (Unrelated to “organic” food labeling.) 

• Inorganic: Combined with non-carbon elements; more toxic and classified as a carcinogen. Found in industry, building materials, and contaminated water. 

• Arsine gas: A highly toxic, flammable gas with a garlic-like or fishy odor, produced when arsenic-containing metals are treated with acid. 

How Are Consumers Exposed To Arsenic?

The primary human exposure to arsenic is through ingestion of inorganic arsenic-contaminated drinking water. Inorganic arsenic can be naturally occurring in groundwater; in certain locations, it can also enter groundwater through industrial processes, such as mining, fracking, coal-fired power plants, arsenic-treated lumber, and arsenic-containing pesticides. Arsenic levels tend to be higher in groundwater sources, such as wells, than surface sources, such as lakes or reservoirs.  

Exposure to arsenic through food is generally less frequent; it is in crops grown in soil or groundwater contaminated by arsenic. Foods with higher levels of arsenic include rice, rice-based products, grains, shellfish, and mushrooms. Average daily dietary arsenic intake is around 40 micrograms (µg), with 1–20 µg from inorganic arsenic. 

How Much Arsenic Is Safe? 

Arsenic is toxic to humans and can affect people of any age or health status. The potential for long-term adverse health effects from consuming food contaminated with arsenic varies depending on the level of arsenic in the food; age of the consumer; length, amount, and frequency of exposure to arsenic in the food; and other potential exposures happening at the same time—either to arsenic from other sources, or other contaminants, or to beneficial nutrients. 

Current research indicates that inorganic arsenic is more dangerous than organic arsenic and the health effects from exposure are more severe. Organic arsenic compounds contain arsenic with carbon and are not related to organic farming practices. Some scientific studies have shown that two forms of organic arsenic found in certain foods, dimethylarsinic acid (DMA) and monomethylarsonic acid (MMA), may be a health concern. The FDA is monitoring emerging research on possible health risks from these forms of organic arsenic and will continue to monitor both inorganic and organic forms of arsenic in foods. 

What Health Risks Are Associated With Overexposure to Arsenic?

For adults, long-term exposure to inorganic arsenic has been associated with skin disorders and increased risks for skin, bladder, and lung cancers, and for cardiovascular disease. For people of all ages, short-term exposure to very high amounts of inorganic arsenic can result in nausea, vomiting, bruising, and numbness or burning sensations in the hands and feet. 

Fetuses, infants, and children are particularly vulnerable to the potential harmful effects from arsenic exposure because of their smaller body sizes and rapid metabolism and growth. Exposure to high levels of arsenic during times of active brain development is associated with adverse neurological effects such as learning disabilities, behavior difficulties, and lowered IQ.  

Chronic low to moderate exposure to inorganic arsenic can cause DNA damage, oxidative stress, and increased risks for cancers (skin, lung, bladder), respiratory disease, heart disease, and chronic kidney disease. In utero exposure is linked to miscarriage, stillbirth, infant mortality, neurodevelopmental issues, and congenital heart disease. Arsenic can cross the placenta but is minimally transferred through breast milk. 

There is no universally accepted biomarker to evaluate chronic exposure to inorganic arsenic. Hair and nails can indicate long-term exposure; blood and urine reflect recent intake. 

What Is Being Done To Reduce Arsenic In Food?

U.S. and global regulators set safety limits for heavy metals in food and water. The U.S. Food and Drug Administration (FDA) is the lead U.S. Agency for protecting the public from overexposure to heavy metals in food. It regulates and provides guidance for industry to reduce the levels of heavy metals in food. U.S. initiatives like FDA’s Closer To Zero program are actively working to reduce exposure to heavy metals for all ages. 

If the FDA determines that the level of arsenic causes the food to be unsafe, the agency will take regulatory action. This may include working with the manufacturer to resolve the issue, and as necessary, taking steps to prevent the product from entering, or remaining, in the U.S. market. Several examples include: 

• The FDA limits the level of arsenic (as well as other contaminants) in bottled water by establishing allowable levels in the quality standard for bottled water. This level is set to 10 ppb, the same amount allowed by the U.S. Environmental Protection Agency (EPA) for public drinking water. 

• The FDA is focusing on inorganic arsenic levels in foods commonly consumed by young children, and recently set an inorganic arsenic limit of <10 parts per billion (ppb) or 10 micrograms/kilogram (µg/kg) in apple juice and <100 ppb in infant rice cereals.  

The FDA also issues guidance for industry to describe the agency’s current thinking on a regulatory issue. For example, guidance on action levels communicates to industry the level of contaminants in foods at which the FDA may take enforcement action.  

How Can Consumers Lower Their Exposure To Arsenic? 

The main way consumers can limit exposure to arsenic is to have drinking water tested. There is currently no regulation for arsenic in private wells, so if a home does not use a public water system, the state certification officer can be contacted for a list of laboratories to test home drinking water. Filtration methods like reverse osmosis or ion exchange can remove arsenic. 

To reduce exposure to lead through food, consumers should eat a variety of nutrient-dense foods across and within the main food groups of vegetables, fruits, grains, dairy, and proteins. Consistently eating a variety of healthy foods can help protect consumers by limiting heavy metal exposure from a specific food and promoting good nutrition. 

Since rice can contain more arsenic compared to other grain sources, varied food sources of rice-based products and an increase in the variety of other grains like quinoa, oats, and barley is recommended, particularly for infants and children.  

From birth to 6 months of age, babies should only be given breastmilk or iron fortified infant formula and delay the introduction of cow’s milk, fortified soy products or fruit juice until at least one year of age.   

References 

1. Arsenic and Inorganic Arsenic Compounds, 15th Report on Carcinogens, National Toxicology Department, U.S. Department of Health and Human Services, 2021. Retrieved here on 11/14/2024.  
2. Arsenic in Food, U.S. Food and Drug Administration, 2024. 
3. Arsine, PubChem, National Library of Medicine, Retrieved here on 11/14/2024.  
4. Arsenic, World Health Organization, December 7, 2022. Retrieved here on 11/14/2024.  
5. Arsenic, National Institute of Environmental Health Sciences. Retrieved here on 11/14/2024.  
6. Update of the risk assessment of inorganic arsenic in food, EFSA Panel on Contaminants in the Food Chain (CONTAM), 18 January 2024. Retrieved here on 11/14/2024.  
7. Closer to Zero: Reducing Childhood Exposure to Contaminants from Food, U.S. Food and Drug Administration, September 16, 2024. Retrieved here on 11/14/2024.  
8. FDA Issues Final Guidance to Industry on Action Level for Inorganic Arsenic in Apple Juice, U.S. Food and Drug Administration, June 1, 2023. Retrieved here on 11/14/2024. 
9. Lim KT, Shukor MY, Wasoh H. Physical, chemical, and biological methods for the removal of arsenic compounds. Biomed Res Int. 2014;2014:503784. doi: 10.1155/2014/503784.  
10. What You Can Do to Limit Exposure to Arsenic, U.S. Food and Drug Administration, April 27, 2022. Retrieved here on 11/14/2024.