Key Points About Biomonitoring

• Biomonitoring is the measurement of specific substances in the human body, usually through the analysis of blood, urine, milk or other tissues. Using biomonitoring studies in blood and/or urine, CDC researchers can identify the physical evidence of an exposure to a particular substance-at extremely low concentrations.

• Advances in biomonitoring technology allow scientists to detect greater numbers of substances and to measure them at smaller and smaller levels in human fluid and tissues. Recent developments have made it possible to measure even trace, background-level exposure to environmental chemicals.

• Biomonitoring data can be very useful in understanding the extent to which people and populations have been exposed to particular substances and can provide guidance for additional research. However, biomonitoring data do not provide information about (1) the source(s) of an exposure, (2) how long a substance has been in the body, or (3) what effect, if any, a substance may have on human health.

Biomonitoring technologies are important and powerful tools to help scientists better understand human exposure to both naturally occurring substances and those resulting from products of modern society. The interaction among the potential effects of our environment - including physical, biological, social, behavioral and chemical factors that can have both positive and negative effects on human health - is complex. As biomonitoring technology continues to advance, more information is being made available to help scientists, medical professionals and policy makers enhance public health.

• Americans are living longer, healthier lives. Public health officials attribute this increased longevity to factors such as clean drinking water, life-saving vaccines and medicines, and the availability of diverse and healthful foodstuffs. In fulfilling this important role, natural substances and manmade products in our modern lifestyle can become a small but measurable component of our environment. Our bodies absorb natural and manmade substances from eating, drinking, breathing and through dermal contact.

• The human body is made of thousands of chemical substances, such as vitamins, nutrients, proteins, and hormones, which are essential to life. While some of these chemicals are generated within our bodies, others are absorbed by eating, breathing, and through contact with our surroundings. Throughout our lives, humans and other organisms are continually exposed to environmental chemicals, both naturally occurring (from air, water and soil or produced by plants, animals and natural events, such as forest fires and volcanoes) and manmade (pharmaceuticals, soaps, disinfectants, auto exhaust, and other pollution, etc.)

According to the Centers for Disease Control and Prevention (CDC): "Just because people have an environmental chemical in their blood or urine does not mean that the chemical causes disease."

• Biomonitoring data demonstrate that pollution controls have reduced exposure to many potentially harmful environmental chemicals, including lead and mercury. These CDC data can inform public health policy by assisting policymakers and researchers to examine and determine the efficacy of societal controls, such as smoking restrictions, auto emissions controls, and other strategies.