Reproductive health and chemical exposure

A review of the evidence for links between declines in human reproductive health and our exposure to hazardous chemicals There is a growing body of evidence which indicates a disturbing rise in the incidence of disorders of the human reproductive system. For example:
 
* sperm counts have declined dramatically over the past 50 years in many countries
* testicular cancer has increased significantly
* infertility may now affect 15-20% of couples in industrialised countries compared to 7-8% in the early 1960s
* girls are reaching puberty at an earlier age in some parts of the world
* the incidence of endometriosis in women is high in some countries
* the number of boys born compared to the number of girls has shown declines in several regions, with marked changes in some areas.
 
The exact causes of the increase in reproductive problems are presently unknown. However, in parallel with the increase there has been a rise in the manufacture and use of many chemicals. It has been estimated that every year around 100,000 different types of chemicals are produced and used around the world. The use of chemicals has led to the inevitable contamination of the environment and consequently, also to human exposure. Many chemicals have been found to contaminate human tissues and even the developing foetus in the womb is exposed to a multitude of chemicals which pollute the human body.
 
Although not proven beyond doubt, there is increasing evidence of a possible link between the synonymous rise of reproductive health problems and the rise of our exposure to many chemicals. The presence of many man-made chemicals at current environmental levels may already be negatively impacting the reproductive health of wildlife and humans. The grounds for such a hypothesis draw on a number of lines of evidence, including laboratory studies on effects of chemicals in animals, direct measurements of chemical exposure in humans (including presence of chemicals in body tissues) and the findings of correlations between level of exposure to chemicals and incidence of certain disorders.
 
Laboratory studies have shown beyond any doubt that certain chemicals are capable of causing reproductive disorders in animals.