13.6.2012 WHO confirms that diesel causes cancer

The World Health Organisation (WHO) has raised the status of diesel exhaust fumes from 'probable carcinogen' to 'carcinogen' – a shift that the WHO's science panel have considered very important due to the amount of people that are exposed to diesel fumes.

Experts in Lyon analysed both animal and human research and published studies to formulate their conclusions. One particular paper investigated over 12,000 miners over several decades from 1947, concluding that those exposed to diesel fumes had a higher risk of developing fatal lung cancer.

Kurt Straif, director of the International Agency for Research on Cancer (IARC) department that evaluates cancer risks said that there could be many cases of lung cancer that are connected to the contaminant. He said: "It's on the same order of magnitude as passive smoking... this could be another big push for countries to clean up exhaust from diesel engines."

Straif identified particular groups of people that may be at risk from diesel fumes, which included pedestrians on the streets, ship passengers and crews, railroad workers, truck drivers, mechanics, miners and people operating heavy machinery.

The new classification to 'carcinogen' came about as the result of a week long discussion in Lyon, France, organised by the IARC, part of the WHO. The risks of diesel as a carcinogen had not been revised since 1989, when it was not considered such a serious threat.

While the WHO's latest position is of great significance globally, there is good reason to recognise that many newer diesel engines emit less harmful gases – while in the US, diesel fumes are still considered a 'likely carcinogen', Vincent Cogliano of the US Environmental Protection Agency said: "We don't have enough evidence to say these new engines are zero risk, but they are certainly lower risk than before."

In the UK and Europe, European directives have been instrumental in reducing what are known as the 'regulated emissions' which includes particulate matter up to 10 microns in size (PM10). First introduced in 1992, these form a set of rolling regulations designed to become more stringent year on year. Currently limits for new cars must conform to 'Euro V' standard. Since 2001, PM10 standards have reduced particulate emissions from new cars by a factor of 10.

However, there is some concern as the portion of diesel cars sold in the UK has risen steeply in recent years. This is due to improved quality and drivability of diesel cars from new technologies, and the fact that smaller diesel engines with lower CO2 figures are attractive with the introduction of CO2 based financial incentives, such as tax.

WHO, The Guardian, UK Press Association