• For children, there is no known safe level of arsenic in food.
• Arsenic can cross the placenta, increasing the likelihood of exposure to the fetus. There is minimal exposure from breast milk.
• Recent reports have described inorganic arsenic levels in a variety of foods, including rice and rice milk; cereal and energy bars sweetened with rice syrup; and apple juice and baby food.
• Low-level inorganic arsenic exposure from food products may be associated with learning development and neuromotor function delays in children.
• Health care providers can encourage families to consume a varied diet.

Arsenic occurs naturally in both organic (typically non-toxic) and inorganic forms. Inorganic arsenic is toxic and carcinogenic (cancer-causing). Arsenic is a naturally occurring element, found widely in the environment as an inorganic salt. Groundwater may flow through arsenic-containing bedrock or soil, contaminating drinking water drawn from wells. Past use of arsenic-containing pesticides and fertilizers may also contaminate fields where rice (which selectively absorbs arsenic) and apples are grown.^1,2

In addition to being naturally present in the environment, it has also been used for many years for industrial purposes, including pest control, animal antimicrobial treatment, wood preservation, petroleum refining, and in the mining/smelting industries. Most industrial uses of arsenic employ the more toxic inorganic forms. Release of arsenic through these processes can lead to increased inorganic arsenic in the atmosphere, in water, and in soil. Workers in industrial processes and communities near these industries may be exposed to arsenic from coal-fired power plants, hardening metal alloys, purifying industrial gases, and in the electronics industry in the form of gallium arsenide and arsine gas as components in semiconductor devices. Arsenic has been reported in imported folk or homeopathic remedies.³  

Although inorganic arsenic can cross the placenta, increasing the likelihood of exposure to the fetus, arsenic may be found, as noted above, in water and food. In addition to inorganic forms of arsenic, there are organic forms found in seafood (farm-raised and wild) that are generally
considered non-toxic.⁴

There is no level of inorganic arsenic in food that is safe. An ingestion of a very high amount of arsenic-containing product can cause a serious sudden illness. Chronic high-level inorganic arsenic exposure, as from elevated water levels, has been associated with chronic skin problems and future development of a variety of adult cancers of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate, as well as respiratory and cardiovascular disease, but patients are unlikely to complain of specific symptoms or signs. Low-level exposure, more typical of some well water or food products, has possible health effects on learning and neuromotor function in children. It is important for health care providers to have an index of suspicion for arsenic-based on suspected or confirmed exposure to some well water or food.

Most arsenic exposures are chronic, without obvious symptoms or signs, and so medical management shifts to prevention, mitigation, and risk assessment. If, despite avoidance of arsenic (primarily in water and food), there is remaining concern or clinical suspicion for potential ongoing arsenic exposure; a quantitative timed urine specimen (8 or 12 hours in children 24 hours in adults; a first morning “spot” urine, along with a urine creatinine to correct for concentration, is less accurate). An acid-washed container should be used to avoid sample contamination. If the laboratory reports total arsenic, it should be “speciated” or fractionated to distinguish between the toxic inorganic species (if present) as well as the organic species (currently considered non-toxic) typically found in seafood. Consultation with laboratory staff is recommended before ordering the test. For more information, visit Agency for Toxic Substances and Disease Registry (ATSDR) Arsenic Toxicity website.

United States (US) Environmental Protection Agency (EPA) has an enforceable maximum contaminant level (MCL) for municipal water supplies of less than or equal to 10 micrograms of arsenic per kg of water (10 parts per billion, or ppb), to protect from chronic arsenic exposures, and a non-enforceable MCL goal of 0 ppb, which reflects the level at which no adverse health effects are expected.⁵ Some states have lowered the level to 5 ppb. The US Food and Drug Administration (FDA) has tested various foods for arsenic, finding, for example, elevated levels in rice⁶, and proposed a limit for inorganic arsenic of 100 ppb in infant rice cereals in 2016⁷; this action level was adopted in 2020.⁸

The risk of chronic exposure to low-level arsenic can be mitigated through a varied diet. Infants
who have a restricted diet (e.g., rice cereal as a first solid food and juice) may have arsenic
exposures that are proportionately higher than those in older children and adults. FDA conducts
routine surveillance for arsenic in apple juice and generally levels have been below 10 ppb, the
same level allowable in drinking water.⁹ Children’s toys are tested and must demonstrate compliance with Consumer Product Safety Commission (CPSC) regulations that limit arsenic in toys that may be mouthed. Until more is known, providers can advise families to:

• Encourage breast milk for the first 6 months of life, as it has little to no arsenic.¹⁰
• Test well water for arsenic, and consider bottled water if results exceed EPA recommendations, particularly if water is used to reconstitute formula.¹¹ Reverse-osmosis filters can mitigate arsenic in water but must be maintained regularly; an iron-
  impregnated biochar has been shown to perform as a low-cost arsenic sorbent.¹²
• Consult with local or state environmental health agencies to determine the potential
  for arsenic in drinking water, especially important for private well users, as these
  systems are not regulated by EPA.
• Choose rice products, including baby food, that are lower in inorganic arsenic.¹³
• As part of a varied diet, limit the serving size and frequency of foods that may have
  higher inorganic arsenic content, such as rice. Manage fruit juice consumption as part
  of a healthy diet per the recommendations for children from the American Academy of
  Pediatrics (AAP).¹⁴ 
• Avoid rice milk for younger children.
• Avoid products sweetened with brown rice syrup.
• Parboil rice (brown or white) before cooking, or wash and pre-soak rice (effective only for white) before cooking to reduce inorganic arsenic.¹⁵
• Avoid smoking, as cigarette smoke contains arsenic.
• Do not use older, arsenic-containing pesticides (now banned in the US).
• Do not allow children to play in areas or structures known to have arsenic contamination. Avoid sawing, sanding, or burning “pressure-treated” chromated copper arsenate (CCA)-containing lumber; do not grow vegetables in planters made of CCA-containing lumber