A report released January 26, 2015, by The Health Effects Institute, revealed that a collaborative research study has concluded that lifetime inhalation exposure to emissions from heavy-duty 2007-compliant diesel engines did not increase cancer risk in rats.  This was the first comprehensive, peer-reviewed report on this topic, and it was issued by a specially convened review panel which considered the results of four collaborative studies on the topic.

In 2007, both the United States E.P.A., as well as the California Air Resources Board, adopted stringent new regulations for heavy-duty highway diesel engines, greatly reducing the acceptable standard for particulate matter emissions.  In response, the industry introduced new technologies which were expected to substantially reduce emissions from diesel engines.  To test this expectation, the Advanced Collaborative Emissions Study (ACES) program instituted four studies conducted as a single phase to investigate the health effects of emissions compliant with the more stringent 2007 regulations.

The results confirmed “that [new technology diesel exhaust] would not cause an increase in tumor formation or substantial toxic health effects in rats, although some biologic effects might occur.”  Those potentially adverse effects “were limited to the respiratory tract and were mild and generally seen only at the highest exposure level.” 

To access the complete report and its appendices, use this link: http://pubs.healtheffects.org/view.php?id=430.