Toxic metals linked with heart disease

Environmental exposures as important as other risk factors, say study authors

People with heavy exposure to arsenic, lead, cadmium or copper may be more likely to develop cardiovascular disease, a review suggests.

While these elements occur naturally in the earth's crust, certain metals can also appear at unsafe levels in drinking water, food and air as a result of agricultural and industrial practices, mining and smoking, the research team noted in the BMJ.

Copper and lead, for example, can seep into drinking water from corroded pipes, while arsenic and cadmium can accumulate in groundwater due to runoff from factories and crop irrigation systems, and are also found in cigarette smoke.

For the analysis, researchers examined data from 37 earlier studies with a total of almost 350,000 participants. Overall, about 13,000 people had heart attacks, bypass surgery or other events related to heart disease, and about 4200 had a stroke.

Compared with people with