Traffic fumes can raise lung cancer risk

Exposure to even low levels of traffic fumes is enough to raise the risk of lung cancer, a large new study has warned.
The research analysed pooled information from 17 studies in nine European countries. The data covered almost 313,000 individuals.
Researchers found that over an average 13-year follow-up period, 2,095 study participants developed lung cancer.
They found people's chances of having the disease rose with greater exposure to small sooty particles generated by diesel exhausts which are known to lodge in the lungs.
Experts have suggested that air pollution be added to smoking as a recognised cause of the disease, AAP news agency reported.

"We found no threshold below which there was no risk. The results showed a picture that 'the more the worse, the less the better'," lead scientist Dr Ole Raaschou-Nielsen, from the Danish Cancer Society Research Centre, said.

Traffic pollution was mostly linked to adenocarcinoma lung cancer, the only form of the disease to affect significant numbers of non-smokers.
"At this stage, we might have to add air pollution, even at current concentrations, to the list of causes of lung cancer and recognise that air pollution has large effects on public health," Japanese expert Dr Takashi Yorifuji, from Okayama University, wrote in the journal Lancet.

In the research, two size grades of particle were studied, tiny PM 2.5s and somewhat larger PM10s.
The risk of lung cancer rose by 22 per cent for every density increase in PM10s of 10 micro-grammes per cubic metre of air, the report said.
For PM2.5s, every five micro-gramme per metre cubed increase led to an 18 per cent increase in risk.