The foetal consequences of pollution

Do you believe that by being ecofriendly you are protecting future generations from the menace of pollution? Think again. A new study shows that pollution from coal fires triggers genetic defects that are passed down the generations. Christopher Somers, James Quinn and colleagues from the Ontario-based McMaster University have found that air pollution causes long-term genetic mutation in species as diverse as gulls and mice.

During their study, the researchers raised two groups of mice in two sheds. One shed was located a kilometre away from two steel mills. The other (in a rural area) was 30 kilometres away from the mills, in a direction perpendicular to the prevailing winds. Many coal-fired factories throughout the world produce the same type of pollution as these mills. The mice were studied for 10 weeks. The researchers found that about 20 per cent of the rural controls had mutations in chromosomes inherited from their fathers. But in the other group, however, the rate was 30 per cent. No significant affect was found in the maternal chromosome sequence.

This suggests that the pollution mostly affected the cells that give rise to the sperms. The litter size of the pollution-exposed mice also tended to be smaller, suggesting that lethal mutations had killed some foetuses. "Our findings imply that there is an urgent need to investigate the genetic consequences associated with exposure to industrial pollution," says Somers. Since toxic chemicals tend to cling to tiny air particles, the researchers would check if filtering the air will lower the mutation rate. "We are bound to find a solution," says Somers.