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Diesel engine exhaust does cause cancer
The International Agency for Research on Cancer has re-classified diesel engine fumes as carcinogenic to humans
13th June 2012 - The International Agency for Research on Cancer (IARC), part of the World Health Organisation, previously labelled diesel exhausts as probably carcinogenic to humans. It has now concluded there is sufficient evidence to show that diesel exhaust definitely is a cause of lung cancer and increases the risk of cancer of the bladder.
Here are some FAQs about diesel and cancer.
What is diesel?
Crude oil can be separated into several different types of fuel. One of these is diesel which is heavier and oilier than petrol. It's used to power cars, lorries, buses, boats, trains, cranes, farming equipment and power generators.
Diesel emits very small amounts of carbon monoxide, hydrocarbons and carbon dioxide (emissions said to contribute to global warming) but high amounts of nitrogen compounds and soot.
Does it cause cancer?
According to the IARC it definitely does cause cancer. It reached its conclusion following a week-long meeting of international experts who carried out a rigorous, independent assessment of the scientific evidence. In particular they looked at the results of a large US National Cancer Institute study of underground miners who used diesel-powered equipment. It was published in March 2012 and showed an increased risk of death from lung cancer in exposed workers.
What about the general population?
Although the main studies that led to their conclusion were in workers with a high exposure to diesel exhaust fumes, there is a risk to the general population. In the past scientists have found that initial studies showing a risk in heavily exposed occupational groups were followed by positive findings for the general population. Consequently they believe actions to reduce exposure should encompass everyone: workers and the general population alike.
In the UK there are already guidelines in place to protect employees from the harmful effects of diesel fumes.
What does this mean for public health?
Large populations are exposed to diesel exhaust in everyday life, whether through their occupation or through the ambient air. The IARC says governments and other decision-makers now have a valuable evidence-base on which to consider environmental standards for diesel exhaust emissions.
Already, increasing environmental concerns over the past two decades have resulted in successively tighter emission standards in Europe and the US, for both diesel and petrol engines. For diesel engines, this has meant required changes in the fuel such as marked decreases in sulphur content, changes in engine design to burn diesel fuel more efficiently and reductions in emissions through exhaust control technology.
However, many parts of the developing world lack regulatory standards. The IARC believes exposure to diesel exhaust fumes should be reduced worldwide.
The Department of Health says it's carefully considering the IARC report as air pollutants are a significant public health concern.
The IARC says the risk from diesel exhaust is on a par with passive smoking.
Cancer Research UK says the report sends a clear message that diesel fumes can cause lung cancer but says the overall number of lung cancers caused by diesel fumes is likely to be a fraction of those caused by smoking tobacco.
What about petrol exhaust fumes?
The IARC concluded that petrol exhaust fumes are possibly carcinogenic to humans. This is the same as it found in a previous evaluation in 1989.