Why mowing the lawn is bad for you

    By JAMES CHAPMAN
    ... He discovered 26 different PAHs in mower exhaust fumes, including 100 micrograms of benzopyrenes, which is widely implicated as a carcinogen in cigarette smoke.

    They take only one hour to generate the same level of carcinogens as a car engine on a 100-mile journey, according to a study. Analytical chemist Dr Roger Westerholm, who did the research, said owners should consider fitting catalytic converters to their mowers to reduce the danger. Dr Westerholm, who is based at Stockholm University in Sweden, said the carcinogens were contained in the four milligrams of poly-cyclic aromatic hydrocarbons (PAHs) emitted in one hour\'s mowing. He discovered 26 different PAHs in mower exhaust fumes, including 100 micrograms of benzopyrenes, which is widely implicated as a carcinogen in cigarette smoke. The mowers also produced more than one pound of carbon monoxide and several grams each of methane, hydrocarbons, nitrogen oxides and smoke particles. Dr Westerholm said this was of particular concern because mowerusers would be in close proximity to the exhaust fumes as they cut the grass. \'People are breathing these fumes in,\' he added. Lawnmowers are important sources of PAHs that have not been investigated before. \'Some of these chemicals have been found to be carcinogenic in animals, and I would expect them to be carcinogenic in humans as well.\' Dr Westerholm said the four-stroke, unleaded petrol engine he tested was \'typical\' of most modern lawnmowers. \'It\'s not good for your health,\' he warned. \'I would solve the problem by using an electric lawnmower or by fitting a catalytic converter to petrol engines.\' Dr Westerholm, whose findings appear in the magazine New Scientist, said other petrol-powered garden tools, such as leaf blowers and chainsaws, should also be fitted with converters. \'In the tests, they cut PAH emissions by more than 90 per cent,\' he explained. \'They also cut most other pollutants by between 30 per cent and 50 per cent. Using a catalyst would help prevent most emissions from small engines.\' Lawnmower manufacturers dismissed the study as scaremongering last night. A spokesman for Atco-Qualcast, one of Britain\'s biggest manufacturers, said: \'All modern petrol lawnmowers meet stringent emission regulations laid down by the EU. \'In Britain, more than 70 per cent of all lawnmower sales are electric. \'Petrol mowers are used mainly in larger, private gardens or public parks. In these open space environments, there is no concentration of emissions. \'Work by the engine manufacturers continues to reduce both emissions and noise. We believe there is no cause for concern.\' Peter Marsh, director of the Garden Industry Manufacturers Association, said there had been no previous evidence that emissions from lawnmowers were a danger to health.