Men living in congested inner-city areas or close to main roads may be at increased risk of prostate cancer, a new study reveals.
Experts called for urgent action to tackle air pollution after evidence suggested traffic and industrial fumes may contribute to the onset of the disease, which kills 12,000 men in the UK each year.
The study, based on data from 220,000 men in Britain, found those exposed to higher levels of pollution were 6.9 per cent more likely to be later diagnosed with prostate cancer than those who were not—a risk that increased as exposure to air pollution levels also increased.
Researchers believe the biggest culprit is nitrate, or NO3, which comes from car exhausts.
And while the precise mechanism is unclear, it is already known that nitrogen, a key component of NO3, can fuel cancer cell growth.
The study is the latest to examine the possible links between air pollution and prostate cancer.
Most have looked at levels of tiny toxic particles known as PM2.5, which are much smaller than a human hair and can be inhaled deep into the lungs.
These particles come from vehicle exhausts, industrial and agricultural emissions, and burning domestic fuel inside homes. But in the new study, scientists also looked at the effects of five of PM2.5's main constituents, including NO3.
The study used data from 224,000 men with an average age of 58, who were followed up for 13.7 years.
Of those, 5 per cent were diagnosed with the disease and the researchers calculated how much pollution they had been exposed to based on their postcodes.
The results suggested pollution was associated with a small increase in risk, and that NO3 contributed the biggest effect.
Writing about their study in the Journal of Urology, the scientists from Peking University in China, said: 'Our findings suggest that "where you live" matters alongside "who you are" (genetics) and "what you do" (lifestyle). 'Our results highlight the urgent need to target nitrate emission sources, specifically traffic and agriculture, to reduce the disease.'
Around 63,000 men in the UK are diagnosed with prostate cancer each year.
The Mail, along with Prostate Cancer UK, has long campaigned for men to be offered regular PSA tests as part of a screening programme.