Arsenic is a naturally occurring chemical element found throughout our environment and its living systems. Arsenic can enter groundwater through erosion and weathering of soils, minerals, and ores. Arsenic compounds are used in the manufacture of a variety of products and may enter our environment directly from industrial effluents and indirectly from atmospheric deposition.
Arsenic exists in different chemical forms, which can be classified into two groups: organic arsenic and inorganic arsenic. Inorganic arsenic is considered to be the most toxic to human health, while organic arsenic is considered to be non-toxic.
Arsenic can be found at very low levels (low parts per billion [ppb]) in many foods, including meat and poultry, milk and dairy products, bakery goods and cereals, vegetables, and fruits and fruit juices. These traces levels of arsenic generally reflect normal accumulation from the environment. Both organic and inorganic forms of arsenic can be found in food. While the levels of each depend on the type of food, inorganic arsenic is not usually found at high levels.
Higher levels of arsenic are generally found in fish and shellfish, but in the organic form, which is not of concern to human health.
Inorganic arsenic is not usually found at high levels in food. Long-term exposure (over many years or decades) to high levels of inorganic arsenic is known to contribute to the risk of human cancer and can affect the gastrointestinal tract, kidneys, liver, lungs and epidermis.
Short term exposure (days/weeks) to very high levels of inorganic arsenic can also cause various health effects including skin effects, nausea, diarrhea, vomiting and numbness in hands and feet.
Current scientific evidence does not clearly indicate that infants and children are more susceptible than adults to the toxic effects of arsenic. However, due to the smaller body weights of infants and children, which can result in greater exposures to contaminants, a more precautionary approach is often taken when assessing the possible risks of chemical exposure to children, to help mitigate any possible risks.
Because inorganic arsenic is a human carcinogen, every effort should be made to maintain levels in food as low as reasonably achievable. Health Canada assesses any findings of elevated levels of arsenic in food on a case-by-case basis using the most current science available. When levels of arsenic deemed unsafe are found in food, Health Canada and the Canadian Food Inspection Agency take appropriate actions such as public recalls, product detention, and the establishment of maximum levels.
Health Canada continues to conduct regular surveillance of chemicals such as arsenic in food. Health Canada also collaborates with the Canadian Food Inspection Agency and the food industry to ensure that any foods containing arsenic at levels hazardous to human health do not reach the consumer. Additionally, Health Canada continues to evaluate the human health risks associated with exposure to contaminants from food as new data and information become available.
Levels of arsenic found in food sold in Canada are generally very low, and as such there is no need to change dietary habits to reduce exposure to arsenic.
Health Canada continues to recommend that Canadians consume a variety of foods from each food group according to Eating Well with Canada's Food Guide.