Study looking at impact of post-2010 US diesel engine emissions on rats finds no evidence of lung cancer tumours
A US academic health study of lifetime animal exposure to new technology diesel engines claims to have found no evidence of carcinogenic lung tumours – a conclusion welcomed by the US diesel vehicle industry.
Published this week (January 27) by Boston-based independent research body the Health Effects Institute (HEI), the study also concluded that concentrations of particulate matter and other air pollutants emitted from new technology diesel exhausts from 2010 or later are more than 90% lower than emissions from traditional, older diesel engines.
The study exposed laboratory rats for 80 hours a week for up to 30 months to emissions from a heavy duty diesel engine, which met 2007 US Environmental Health Protection Agency (EPA) emissions standards requiring filters and other technology to aimed at reducing emissions.
And, while a “few mild changesâ€? were seen in the rats’ lungs consistent with long-term exposure to nitrogen dioxide, the study found that lifetime exposure did not induce tumours or pre-cancerous changes in the lung, nor increase tumours related to diesel in any other tissue.
HEI, which is jointly funded by the US Environmental Protection Agency and industry, said it expected the study results to play an important role in future risk reviews of diesel engines by international agencies.
President of HEI, Dan Greenbaum, said: “We are already seeing a transition in America’s roads with over 30% of the trucks and buses in use today meeting these new standards and the trend is growing in Europe as well. These results confirm the great strides that government and industry have made to reduce diesel risk – and argue for even greater efforts to accelerate the replacement of older diesel engines.â€?
Bob O’Keefe, vice president of HEI and chair of Clean Air Asia, said: “These results are impressive for what they can mean for reducing exposure in the US and Europe, but also for the promise they hold in the developing countries of Asia and elsewhere in the world. Countries like China are already moving toward implementing the ultra-low sulfur diesel fuel that is required for these new cleaner technologies.â€?
The findings add to the air quality debate over diesel in the UK, where Labour’s shadow environment minister Barry Gardiner this week told Channel 4’ Dispatches TV programme that the decision to incentivise the purchase of diesel vehicles under the Labour government was the “wrong decisionâ€?.
Meanwhile, the Society of Motor Manufacturers and Traders (SMMT) in the UK recently criticised Islington and Hackney councils’ decisions to levy higher packing permit charges against diesel car drivers in a bid to improve air quality as “unfairâ€? (see airqualitynews.com story).
SMMT clams that all diesel cars built since 2010 have filters which capture more than 99% of particulates, and that new Euro-6 standards will “all but eliminate diesel particulates and dramatically reduce NOx emissionsâ€?.
In addition, the Diesel Technology Forum (DTF) in the US – a non-profit organisation ‘dedicated to raising awareness about the importance of diesel engines, fuel and technology’ – welcomed the “extremely significantâ€? HEI study findings.
Executive director of the DTF, Allen Schaeffer, said: “The significance of this study and its conclusions cannot be overstated. The results of this new study verify the environmental benefits of the new clean diesel technology, which have near-zero emissions for nitrogen oxides (NOx), hydrocarbons (HC) and particulate matter. And while this study focused on heavy duty truck emissions, the new clean diesel technology has the potential for impacting all sectors, including passenger cars, agriculture, construction, maritime and transportation.
“The comprehensive nature of this study by such an authoritative body as the Health Effects Institute is extremely significant. It’s also important to highlight that the U.S. Environmental Protection Agency (EPA), the California Air Resources Board, the U.S. Department of Energy (DOE) and the U.S. Federal Highway Administration are sponsors of this study in conjunction with the manufacturers of emissions control equipment.â€?
The study – ‘Advanced Collaborative Emissions Study (ACES): Lifetime Cancer and Non-Cancer Assessment in Rats Exposed to New-Technology Diesel Exhaust’ – is available on the HEI website.