Selenium levels in human blood, urine, and hair in response to exposure via drinking water.

Blood, hair, urine, and tap water samples were obtained from participants in a population exposed to varying amounts of selenium via water from home wells. Concentrations of selenium in urine and hair produced significant positive correlations with well-water selenium levels. Blood selenium with well-water selenium did not produce a significant correlation. Urine selenium correlation with hair selenium and urine selenium correlation with blood selenium were found to be significant. No significant correlation for hair selenium with blood selenium was found. We conclude that blood selenium alone is not an adequate monitor of selenium exposure or body burden at levels below chronic toxicity.