With Patrick Crow
from Washington, D.C.
The National Research Council says more studies are needed on the health effects of the gasoline additive methyl tertiary butyl ether.
At the request of the U.S. Environmental Protection Agency, the arm of the National Academy of Sciences critiqued a draft study by the White House Office of Science & Technology Policy.
The report, one in a series of studies of MTBE by government and private organizations, found that MTBE does not pose a substantial human health risk but calls for more definitive data.
Effects murky
Bailus Walker, a Howard University professor who chaired the study panel, said, "The effects of MTBE and other oxygenates are still relatively unknown, even though they now are used widely in the U.S. Specific, well-targeted research is needed to answer questions about potential trade-offs in using these chemicals."
The report also criticized the White House panel's draft for not giving more weight to data that show an increase in short term health problems among workers-service station employees, refinery workers, and others-exposed to MTBE.
It said, "Although no human data are available to indicate that exposure to MTBE is linked to development of acute human disease, the committee considers it noteworthy that the available data consistently indicate that exposure to gasoline containing MTBE in occupational settings is associated with an increased rate of acute symptoms."
The report also said there are no data to show that such health effects are confined to any particular "sensitive subpopulation" as the draft study claimed.
The NRC study said workers for whom there is consistent evidence of an increase in symptoms due to MTBE exposure should be studied in more detail.
The NRC committee agreed with the earlier draft that fuels containing MTBE don't appear to pose health risks substantially greater than those associated with conventional fuels. However, it noted "important deficiencies" in the analysis used in the government's report to assess human health risk from exposure to MTBE.
It said the White House draft's failure to provide some indication of the extent of comparative risk associated with each type of fuel is a serious deficiency and should be corrected.
MTBE focus
The NRC report limited its findings to the federal government's winter oxygenated fuels program started in 1992 and did not consider the newer reformulated gasoline program used in many communities.
The study focused on MTBE, explaining that limited data are available on oxygenates such as corn ethanol, ethyl tertiary butyl ether, and tertiary amyl methyl ether.
The Oxygenated Fuels Association was cheered by the NRC study.
Fred Craft, OFA executive director, said, "The finding of no increased health risk comes as no surprise to anyone who has been following this issue. The oxyfuel program has been improving the air quality for millions of Americans."
Copyright 1996 Oil & Gas Journal. All Rights Reserved.
