HEI study reveals lower concentrations of PM and toxic air pollutants from new-technology diesel exhaust

Results from the final phase of the Health Effects Institute’s (HEI) study on Advanced Collaborative Emissions (ACES), the first comprehensive evaluation of lifetime exposure of rats to exhaust from diesel engines designed to meet strict U.S. emissions regulations enacted in 2OO7, showed no evidence of lung tumors.

HEI is a Boston, Mass.-based non-profit organization in the United States, funded jointly by government and industry to research and evaluate the health effects of air pollution.

The study also confirmed that concentrations of particulate matter (PM) and toxic air pollutants are substantially lower in such “new-technology diesel exhaust” (NTDE) than in traditional-technology diesel exhaust (TDE).

The results are described in HEI Research Report 184, Advanced Collaborative Emissions Study (ACES): Lifetime Cancer and Non-Cancer Assessment in Rats Exposed to New-Technology Diesel Exhaust.

The ACES results are expected to play an important role in future risk reviews of diesel engines by international and U.S. agencies.

“We are already seeing a transition on America’s roads, with over 3O% of the trucks and buses in use today meeting the new standards, and the trend is growing in Europe as well,” said Dan Greenbaum, HEI president.

Evaluation of the effects of lifetime exposure in rats was a key feature of ACES because the results could be compared with the findings of several older studies that evaluated long-term exposure to TDE.