Projection of body burdens to assess the relative risk from exposure to trace elements from coal combustion emissions, drinking water, and diet

This study compares the relative health risk of exposure to seven trace elements from four sources - coal-fired electricity generation with a cold-side electrostatic precipitator, coal-fired electricity generation with a hot-side electrostatic precipitator, drinking water, and diet. The measure used for comparing health risks is body burden, which is the amount of an element accumulating within an exposed subject. Body burdens were used as a measure of risk because the lack of dose-response data restricts the projection of absolute risks of exposure, such as death or illness. Thus, projection of body burdens provides a measure of relative risk that can be used for comparison of impact potential from different sources of exposure. The assessment trace elements - arsenic, cadmium, chromium, nickel, lead, selenium, and zinc - were chosen to represent a range of physiological, environmental, and physical characteristics that affect the amount of accumulation. These factors include: toxicity, absorption, excretion, biological half life, bioaccumulation, biotransformation, volatility, and solubility.