CLARKSBURG -- Diesel school buses may cause increased rates of cancer in the children who ride in them, two non-profit environmental groups report.
But the head of West Virginia's school transportation department says the report is a scare tactic that was designed to achieve those results.
A recent report released by the Natural Resources Defense Council and Coalition for Clean Air estimated that diesel exhaust exposures to children who ride buses for an hour per day, for 10 years, would likely result in an additional 23 to 46 cancer cases per million students exposed.
Researchers from NRDC, the University of Berkeley School of Public Health and the Coalition for Clean Air rode rented school buses along elementary school routes in the Los Angeles area.
The exhaust levels they reported were higher than those documented by the Environmental Protection Agency as posing a significant risk for cancer.
"The levels we measured on some of these buses both surprised and worried us," said Gina Solomon, a NRDC scientist. "Worse still, we have reason to believe that these levels are fairly typical."
Not in West Virginia, says Wayne Clutter, executive director of the state department of school transportation.
"They used 20-year-old buses in the California study," Clutter said. "We have a much newer fleet."
Aged units are unable to burn fuel as cleanly, he said.
Clutter said West Virginia mandated the use of diesel -- which has a less combustible flash-point than gasoline -- about 10 years ago after a fatal explosion killed several students in Kentucky.
"The information I have, is that the survey was done in a way to pretty much assure the results they wanted," Clutter said. "It's the best way to scare people and get attention."
The NRDC report, which acknowledged most school systems in the United States use diesel buses, recommended that systems try to switch over to natural gas or propane fueled buses. Short-term fixes included keeping the windows open and having students ride in the front.
Clutter said West Virginia has experimented with both types of alternative fuel systems.
"We have some natural gas buses in Wood County," he said. "But the cost differential makes them prohibitive.
"The propane buses we had would freeze up and wouldn't start in the winter."
Clutter said a fleet of natural gas buses "may work in the future" when the economic issues are resolved.
The state transports more than 200,000 students to school each day on about 3,600 buses.
Staff writer J.R. Brammer can be reached at 626-1442 or by e-mail at jbrammer@exponent-telegram.com.