But Britain has weakened the proposed European Union regulations to provide safety information on the substances at the behest of the US government.

The research, by doctors at what was then the University of California and at the Boston Medical Center, was restricted to listing only effects that had been found by several different studies and which are often well known.

More than 120 diseases have been definitively linked to pollution, and in another 33 evidence of a link is judged to be "good". For the rest the evidence is "limited".

Nine different pollutants have been "verified" to cause asthma - including four from car exhausts, the subject of an Independent on Sunday campaign - the study shows. Testicular atrophy is caused by oestrogen, increasingly found in British rivers that supply drinking water. Mercury poisoning can cause cerebral palsy, while more than 50 pollutants - ranging from dioxins to PCBs - have been shown to cause cancer.

Other effects include: kidney disease, heart disease, hypertension, diabetes, dermatitis bronchitis, hyperactivity, deafness, sperm damage and Alzheimer's and Parkinson's diseases.

One of the authors, Dr Ted Schletter of the Boston Medical Center, said yesterday: "The human body is in constant conversation with this chemical milieu and some substances have turned out to be important contributors to disease." He said pollution often acted in concert with genetic predispositions to developing particular illnesses.

Dr J Peterson Myers, chief executive of the Virginia-based Environmental Health Sciences, said because science continued to find new effects of pollution, the number of diseases linked to it was "very much higher".

At the last count - more than 20 years ago - more than 100,000 chemicals were in use in Europe. Few have been properly tested.

Blood tests in the UK, the rest of Europe and the US indicate that most people carry potentially hazardous chemicals in their bodies.

The European Commission has been trying to introduce a new directive requiring industry to provide safety information on the 30,000 most common chemicals, but this measure has been watered down because of pressure from the Bush administration.

A leaked cable signed by Colin Powell, the US Secretary of State, complains that the measures "would be significantly more burdensome to industry and government" and would "impact" on US exports to Europe. Tony Blair, President Jacques Chirac of France and Chancellor Gerhard Schröder of Germany wrote a joint letter to the Commission and succeeded in weakeningthe measure.

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