Biomonitoring Home

Environmental Chemicals

CDC's Environmental Health Laboratory develops analytical methods to measure synthetic and naturally occurring environmental chemicals in people. Currently, more than 300 environmental chemicals or their metabolites are measured in human samples (e.g. urine, blood, serum, breast milk, and meconium). For many of these chemicals, CDC produces population-based exposure levels segmented by age, sex, and race or ethnicity. This information is published in CDC's National Report on Human Exposure to Environmental Chemicals.

In addition, CDC scientists work with investigators worldwide on studies to better assess exposure to environmental chemicals. These studies usually focus on potentially vulnerable populations such as young children, women of childbearing age, the underserved, and the elderly. CDC also works with collaborators on studies designed to determine whether a link exists between exposure to selected chemicals and health effects.

Because of the laboratory's expertise in measuring chemicals in people, CDC scientists are often contacted by federal, state, local, and international governments as well as by other health organizations about laboratory issues, such as analytical methods, instrumentation, specimen preparation, quality-control procedures, laboratory safety, and medical interpretation of laboratory results.

National Report on Human Exposure to Environmental Chemicals

The National Report on Human Exposure to Environmental Chemicals (National Exposure Report) is a series of ongoing assessments of the U.S. population's exposure to environmental chemicals. Scientists measure chemicals or their metabolites in blood and urine samples obtained from a random sample of participants in CDC's National Health and Nutrition Examination Survey (NHANES). Data are presented for the population as a whole and for subgroups characterized by age, sex, and race or ethnicity. This data provide unique exposure information to scientists, physicians, and health officials. Public health officials can use the data to:

Determine which chemicals get into people and at what concentrations.
Determine, for chemicals with a known toxicity level, the proportion of the population with toxicity levels associated with adverse health effects.
Establish reference ranges that can be used by physicians and scientists to determine whether a person or group has an unusually high exposure.
Assess the effectiveness of public health efforts to reduce exposure of people to specific chemicals.
Determine whether exposure levels are higher among minorities, children, women of childbearing age, or other vulnerable groups.
Track, over time, trends in levels of exposure of the population.
Set priorities for research on human health effects of exposure.