Arsenic in Environment & Heart Attack, Stroke Risk
Researchers suspect groundwater and certain foods raised levels of chemical in study of Native Americans
Study participants provided urine samples that the research team used to estimate their exposure to inorganic arsenic.
Of the participants, nearly 450 died of cardiovascular disease and almost 1,200 developed either fatal or nonfatal cardiovascular disease. Researchers found that a person's risk of death from cardiovascular disease increased with their arsenic exposure.
The one-quarter of patients who showed the highest levels of arsenic in their urine had about a 50 percent increased risk of death by heart attack or stroke compared to those with the lowest levels of arsenic, Navas-Acien said.
Arsenic exposure also was associated with an increased risk of developing cardiovascular disease.
"The paper is very important," said Alice Lichtenstein, a distinguished professor of nutrition science and policy at Tufts University. "It's an area where we need to look more carefully. It gives other research groups another variable to address." She was not involved with the study.
Lichtenstein, however, noted that the study did not draw a direct link between arsenic and heart disease, but instead found a correlation between the two.
"We don't know what the direct effect is. What is important is that we gather more information, which I hope will be done promptly," said Lichtenstein, who also is the director of the cardiovascular nutrition laboratory at the university. "We should not discount this. It's very important. But I think we need a little more information."
People who are concerned about their arsenic intake should have their drinking water tested, Navas-Acien said.
"In particular, people who live in small communities or have private wells should be aware of the arsenic levels in their drinking water," she said. "If you use groundwater and you don't know the levels of arsenic in your drinking water, that can be quite dangerous."
Lichtenstein and Navas-Acien agreed that people concerned about arsenic also should mix up their diet.
"The best advice we can give people is to eat food that comes from a variety of different regions, as opposed to being raised in a single location," Lichtenstein said.
People also should vary their day-to-day eating patterns, Navas-Acien said.