Food Safety Focus (3rd Issue, October 2006) – Food Incident Highlight

Arsenic in Fish

Some concerns were raised recently over arsenic levels detected in fish, including Cololabis saira (also commonly known as pacific saury or sanma).

Arsenic is a metalloid present naturally in the earth's crust. It exists as a natural contaminant in both organic and inorganic forms in foods, with the inorganic form of particular toxicological concern. However, arsenic in fish is usually present in its less toxic organic form. The primary route of arsenic exposure in humans is mainly through ingestion of foods, especially aquatic foods.

Chronic toxicity due to arsenic may lead to skin lesions, nerve damage, skin cancer and diseases of the blood vessels.

Risk assessment study conducted by the Food and Environmental Hygiene Department in 2002 found that dietary exposure to arsenic for both average and high consumers of secondary school students fell well below the safety reference value established by international food safety authorities. Therefore, people with a usual dietary habit was unlikely to experience toxicological effects of arsenic.

According to previous local surveillance results, very few fish samples exceeded local regulatory standard for arsenic and there is no cause for undue concern. The Centre for Food Safety will continue to monitor arsenic content of local foodstuffs, seafood in particular. The public is advised to take a balanced diet so as to avoid excessive exposure to contaminants from a small range of food items.

Illustration: Cololabis saira