Low cadmium levels linked to death in men.
Menke, A, P Muntner, EK Silbergeld, EA Platz and E Guallar. 2009. Cadmium levels in urine and mortality among US adults. Environmental Health Perspectives 117:190–196.
At the low exposure levels of cadmium found in the general US population, men had an increased risk of death due to all causes, cancer and cardiovascular disease.
To date, excess deaths due to cancer -- lung, prostrate and renal -- and cardiovascular disease have been found in people with high and occupational exposures to cadmium. This is the first study to show similar results in the general population. It is the second study to suggest that men, but not women, have increased risk of death due to cadmium exposure.
The authors note that the "potential public health implications of these findings are substantial, because exposure to low levels of cadmium is widespread."
Cadmium is a toxic metal commonly found in the environment due to its use in many products and manufacturing processes. Cigarette smokers and people who work with the metal are exposed to the highest levels. Others are exposed to cadmium through contaminated food, water and air.
Prior studies find that cadmium exposure is correlated to death from all causes, particularly cancer, cardiovascular disease and coronary heart disease. In this study, men had this cadmium associated risk, while women did not. The relationship held for male smokers, ex-smokers and those who had never smoked.
However, cadmium exposure is also linked to cardiovascular problems in both women and men, such as high blood pressure, obesity, diabetes and high cholesterol.
This study of cadmium associated mortality used data collected through the NHANES III, a national survey that best captures exposures and health of the average American. The NHANES III has substantial quality controls to make it a highly regarded rigorous tool to understand health trends in the US population.
Cadmium levels were measured in urine at mean levels of 0.28 micrograms per gram (µg/g) in men and 0.40 µg/g in women. These are far lower than the mean levels between 4.6 and 12.0 found in highly exposed men and women in Japan, according to the authors. Researchers adjusted for lifestyle factors, such as smoking and age.
The cross-sectional study determined the exposure to cadmium at the same time as death was measured. To be certain that cadmium exposure increases death in men, the same results should be found in a study that measured cadmium levels in people who die at a later time.
