Environmental Exposure Map

This page summarizes selected environmental toxins, their common sources, how they are distributed through air, water, dust, materials, and consumer products, and the health effects that have been reported by public health agencies and scientific authorities. It separates conditions with direct toxic effects from conditions that are strongly linked or still under study, because the level of evidence is not the same for every exposure.

EPA states that people in the United States spend about 90 percent of their time indoors, and that levels of several indoor pollutants are often two to five times higher indoors than outdoors.

Primary reference sources: U.S. Environmental Protection Agency (EPA), Centers for Disease Control and Prevention (CDC), Agency for Toxic Substances and Disease Registry (ATSDR), National Institute of Environmental Health Sciences (NIEHS), and related peer-reviewed scientific literature.

The information presented here is based on guidance and summaries from agencies including the U.S. Environmental Protection Agency, the Centers for Disease Control and Prevention, the Agency for Toxic Substances and Disease Registry, and the National Institute of Environmental Health Sciences. For example, CDC states that no safe blood lead level in children has been identified, ATSDR states that some PFAS are linked to harmful health effects but that direct causation in humans is difficult to prove, and NIEHS explains that endocrine disruptors may mimic, block, or interfere with the body’s hormones.