MARIETTA - Following a week-long discussion in Lyon, France, the World Health Organization's cancer agency declared diesel fumes cause cancer, a ruling it said could make exhaust as important a public health threat as secondhand smoke.
It's a claim Marietta City Schools transportation director Dave Davis has heard before.
He said the district has taken steps to address diesel fumes released by school buses.
"We switched to 20 percent bio diesel, which has a lot less soot," Davis said. "We haven't done the retrofit program because it's not really cost effective yet. That's a new filter-type system and they're super high maintenance so we looked at both programs and decided to go with the more cost effective and more efficient which is the bio diesel."
The Ohio Environmental Protection Agency heads up the Ohio Diesel Emission Reduction Grant (DERG) Program in coordination with the Ohio Department of Transportation.
Through the program about $20 million in federal highway funding for clean diesel projects is available this year and next year to replace, repower, retrofit and reduce idling in eligible public sector diesel fleets such as school buses, as well as certain private sector or nonprofit diesel fleets.
The DERG program aims to achieve measurable highway emissions reductions, improve air quality and public health and encourage the transportation sector to clean up diesel fleets and use alternative and cleaner burning fuels.
"All the new buses that come in have the new filter systems in them, that's part of the EPA (program)," Davis said.
Davis noted bio diesel fuel is diesel fuel mixed with 20 percent soybean oil and the district started using it in all of its buses about two years ago. He said it currently costs about the same as diesel fuel.
The World Health Organization's claim linking diesel fumes to cancer comes after a discussion in France by an expert panel organized by the International Agency for Research on Cancer.
The risk of getting cancer from diesel fumes is small, but since so many people breathe in the fumes in some way, the science panel said raising the status of diesel exhaust to carcinogen from "probable carcinogen" was an important shift.
Reclassifying diesel exhaust as carcinogenic puts it into the same category as other known hazards such as asbestos, alcohol and ultraviolet radiation.
The U.S. government, however, still classifies diesel exhaust as a likely carcinogen. Experts said new diesel engines spew out fewer fumes but further studies are needed to assess any potential dangers.
According to Ohio EPA media relations coordinator Erin Strouse, the state of Ohio doesn't have any diesel regulations on the books.
State Rep. Debbie Phillips, D-Athens, said the declaration highlights the importance of taking steps to reduce diesel emissions.
"I think it really does raise the awareness level of the importance of doing anything we can to (reduce diesel fume emissions)," she said. " (That includes) even simple things like encouraging school buses to turn off the engine rather than idling when they're picking up and dropping off children."
Davis said the district established a no idling policy about two years ago, as did other local districts.
"If we're going to be at a building long, everybody's supposed to shut their engines off," he said.
State Rep. Andy Thompson, R-Marietta, said he would like to look into how the World Health Organization drew its conclusion before making a judgment.
"Obviously you're concerned whenever they come to a conclusion with this effect but I try to study and learn more about it before I draw any conclusions," he said.
Experts in Lyon had analyzed published studies, evidence from animals and limited research in humans. One of the biggest studies was published in March by the U.S. National Cancer Institute. That paper analyzed 12,300 miners for several decades starting in 1947.
Researchers found that miners heavily exposed to diesel exhaust had a higher risk of dying from lung cancer.
Lobbyists for the diesel industry argued the study wasn't credible because researchers didn't have exact data on how much exposure miners got in the early years of the study; they simply asked them to remember what their exposure was like.
The Associated Press contributed.