Arsenic is a natural component of the earth’s crust and is widely distributed throughout the environment in the air, water and land. It is highly toxic in its inorganic form.
People are exposed to elevated levels of inorganic arsenic through drinking contaminated water, using contaminated water in food preparation and irrigation of food crops, industrial processes, eating contaminated food and smoking tobacco.
Long-term exposure to inorganic arsenic, mainly through drinking-water and food, can lead to chronic arsenic poisoning. Skin lesions and skin cancer are the most characteristic effects.
Arsenic contamination of groundwater is widespread and there are several regions where arsenic contamination of drinking water is significant. An estimated 140 million people in at least 70 countries have been drinking water containing arsenic at levels above the WHO provisional guideline value of 10 μg/L (4, 5). This is consistent with recent statistical modeling, which suggests between 94 and 220 million people are at risk of exposure to elevated arsenic concentrations in groundwater (6).
The symptoms and signs caused by long-term elevated exposure to inorganic arsenic differ between individuals, population groups, and geographical areas. Thus, there is no universal definition of the disease caused by arsenic. This complicates the assessment of the burden on the health of arsenic.
Similarly, there is no method to distinguish cases of cancer caused by arsenic from cancers induced by other factors. As a result, there is no reliable estimate of the magnitude of the problem worldwide.
In 2010, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) re-evaluated the effects of arsenic on human health, taking new data into account. JECFA concluded that there is some evidence of adverse effects for certain regions of the world where concentrations of inorganic arsenic in drinking water exceed 50–100 μg/L. In other areas, where arsenic concentrations in water are elevated (10–50 μg/L), JECFA concluded that while there is a possibility of adverse effects. These would be at a low incidence that would be difficult to detect in epidemiological studies.
Arsenic poisoning lessions
