Body burden

Body burden is the amount of a harmful substance that is permanently present in a person's body. It is usually expressed in mass units, such as grams and milligrams. The substance may be radioactive or it might be chemically toxic. Many harmful substances can be eliminated naturally by the human body, but some are removed very slowly or not at all. Water soluble molecules are usually easy to remove. Non-polar molecules, on the other hand, are lipophilic and tend to accumulate in fat tissue, which is also non-polar. Large fragments, such as shrapnel, are also difficult for the body to remove.

Body Burden Studies
Since 2000 the Environmental Working Group has spearheaded six studies finding 455 industrial pollutants, pesticides and other chemicals in blood, urine, and breast milk in 72 people altogether, from newborns and grandparents to mothers and teens. They have found that pollution of the human body begins before birth, in complex combinations of chemicals never tested for safety.

The National Report on Human Exposure to Environmental Chemicals provides an ongoing assessment of the U.S. population's exposure to environmental chemicals using biomonitoring. Biomonitoring is the assessment of human exposure to chemicals by measuring the chemicals or their metabolites in human specimens such as blood or urine. The Third Report presents first-time exposure information for the U.S. population for 38 of the 148 chemicals included in the Report. The Report also includes the data from the Second Report; that is, data for 1999-2000.

Campaigns for Awareness of Body Burden
Body burden of chemicals became a mainstream issue as a result of a PBS program reporting on testing of Bill Moyers for a number of groups of toxic chemicals.

The book Our Stolen Future brought world-wide attention to scientific discoveries about endocrine disruption and the fact that common contaminants can interfere with the natural signals controlling development of the fetus.

A number community based organisations campaign for greater awareness of chemical body burden and its possible impact on human health including reproductive systems.

Timing of Exposure
While traditional studies have tried to correlate body burden and cancer at the time of diagnosis, there is increasingly debate on whether it is neo-natal exposure which matters most.

Birnbaum and Fenton review a wide array of experimental evidence from animals showing that exposure to endocrine-disrupting compounds in early development can cause cancer and/or increase sensitivity to cancer-causing agents later in life.