91av

PARTICULATE pollution has been shown to cause irreversible genetic mutations in mice, raising serious concerns about its effect on people.

James Quinn’s team at McMaster University in Hamilton, Canada, reported two years ago that mice exposed to industrial pollution suffer genetic changes (91av, 14 December 2002, p 8). The researchers found changes in regions of “junk DNA” that are particularly susceptible to mutation. This strongly suggests – but does not prove – that pollution also causes a smaller number of mutations in the rest of the genome, potentially triggering all sorts of diseases, from cancers to inherited disorders in children. The researchers could not be sure what was causing the mutations because they simply compared animals at rural and industrial sites.

Now they have repeated the experiment but filtered the air some mice breathed to remove particulates. Their filter removes particles bigger than 0.1 micrometres, so it eliminates almost all particulates, such as PM10s.

The team again found that mice at an industrial site close to steel mills passed on twice as many mutations to their offspring. But mice that had breathed filtered air had similar mutation rates to their country cousins, suggesting that some form of particulate pollution is causing the mutations (Science, vol 304, p 1008).