Biased Dismissal of Epigenetic Evidence for “Clean- Diesel” Carcinogenicity and Genotoxicity

In 2012, the International Agency for Research on Cancer (IARC) named Traditional Diesel Exhaust (TDE) a “known human carcinogen”. Most western nations agreed, passing new regulations. Yet the US denies TDE is a known carcinogen, says scientific data are uncertain, and does not regulate TDE emissions of 80 percent of US-diesel vehicles. It did require post-2007, US-heavyduty- diesel vehicles to have “clean-diesel” or New-Technology-Diesel Exhaust (NTDE) --- filters/engine improvements to reduce emissions. A major reason the US disagrees with the rest of the world is its reliance on the 10-year series of US studies on NTDE, the 2015 Advanced Collaborative Emissions Study (ACES). Co-funded by US Environmental Protection Agency, ACES was overseen by the Health Effects Institute, a research group that the US National Academies of Science earlier praised. Who is right on diesel carcinogenicity, the hundreds of IARC, or the ACES, studies? This review article concludes IARC is correct. It (1) surveys the role of epigenetics in assessing TDE and NTDE carcinogenicity and genotoxicity. Next it (2) shows how, despite some ACES strengths, it ignored much epigenetic evidence for NTDE carcinogenicity and genotoxicity because of wrong/incomplete tests, trimming the data, using incorrect assessment-time frames, making value judgments instead of empirically-confirmed judgments, begging key questions---then invalidly concluding that NTDE causes “only a few mild effects on the lungs,” no cancer or serious ailments, and “no…genedamaging effects.” Finally the article (3) suggests why these scientific errors occurred in prominent studies and (4) answers objections to its criticisms of ACES.