Methyl tertiary butyl
ether (
MTBE) was added to
gasoline on a nationwide scale in 1992 without prior testing of adverse, toxic, or carcinogenic effects. Since that time, numerous reports have appeared describing adverse health effects of individuals exposed to
MTBE, both from inhalation of fumes in the workplace and while pumping
gasoline. Leakage of
MTBE, a highly water-soluble compound, from underground storage tanks has led to contamination of the water supply in many areas of the United States. Legislation has been passed by many states to prohibit the addition of
MTBE to
gasoline. The addition of
MTBE to
gasoline has not accomplished its stated goal of decreasing air pollution, and it has posed serious health risks to a large portion of the population, particularly the elderly and those with respiratory problems,
asthma, and skin sensitivity. Reports of animal studies of carcinogenicity of
MTBE began to appear in the 1990s, prior to the widespread introduction of
MTBE into
gasoline. These reports were largely ignored. In ensuing years, further studies have shown that
MTBE causes various types of malignant
tumors in mice and rats. The National Toxicology Program (NTP) Board of Scientific Counselors' Report on
Carcinogens Subcommittee met in December 1998 to consider listing
MTBE as "reasonably anticipated to be a human
carcinogen." In spite of recommendations from Dr. Bailer, the primary reviewer, and other scientists on the committee, the motion to list
MTBE in the report was defeated by a six to five vote, with one abstention. On the basis of animal studies, it is widely accepted that if a chemical is carcinogenic in appropriate laboratory animal test systems, it must be treated as though it were carcinogenic in humans. In the face of compelling evidence, NTP Committee members who voted not to list
MTBE as "reasonably anticipated to be a human
carcinogen" did a disservice to the general public; this action may cause needless exposure of many to health risks and possibly
cancers.