MTBE - Methyl Tertiary-Butyl Ether

Methyl tertiary-butyl ether (MTBE) is one of variousand urine, for up to two days after contact.
additives used to oxygenate gasoline. TheseWhile not considered as dangerous as Benzene (an
substances are blended with gasoline to reduceelement that MTBE replaces in gasoline) MTBE is a
carbon dioxide emissions (MTBE also reduces othercarcinogen at high enough exposure levels, as shown
toxic chemical compounds in vehicle emissions). MTBEby laboratory experiments on animals conducted by
has been in use since 1979, primarily in response to thethe CDC. However, no governmental bodies have
diminishing use of lead in gasoline.claimed to find sufficient evidence to recognize MTBE
In 1990, with the passage of the Clean Air Actas a possible human carcinogen. Part of this reasoning
Amendments (specifically Section 211), the use ofis that it is eventually broken down and removed from
oxygenated gas was required in areas with excessivethe body, thus long term accumulation is not a risk.
levels of CO air pollution. These areas were primarilySince humans do not encounter MTBE as a separate
urban, meaning that huge numbers of individuals haveentity from gasoline, very few concrete conclusions
been exposed to MTBE. The positive aspect of thehave been drawn since a causal relationship cannot be
blend of gasoline and MTBE (which is highly flammable)adequately established between the chemical and
is that it allows a much cleaner burn and lesshealth conditions.
environmentally harmful emissions. Of the reformulatedSpecifically, the Agency for Toxic Substances and
gasoline (RFG) mandated by this act, over 85%Disease Registry (ATSDR) has still reserved a
contain MTBE.definitive judgment on the adverse health effects of
According to the Environmental Protection AgencyMTBE. Many other studies have been conducted
(EPA), although the use of MTBE appears noble, itsthough and indicate that the following are symptoms
use has caused many health and safety concerns forfound after contact with MTBE.
people who are exposed to it.Symptoms from inhalation include:
Not only can individuals suffer health risks by inhaling* Headaches
MTBE, but the contamination of potable water stores,* Cough
and thus ingestion, are other very real concerns. Water* Nose or throat burning
contamination can happen through the leakage from* Other respiratory irritation
gasoline storage or transport units, most of which are* Lightheadedness
located underground.* Eye irritation
MTBE has a very high level of solubility and there have* Nausea
been many incidences of water contamination all over* Vomiting
the country, especially in places of high population* Dizziness, "spaciness" or disorientation
density (such as California and New England). WhilePossible health issues resulting from ingestion or dermal
MTBE is absorbed quickly into water, it is not similarlycontact (i.e. drinking, swimming or showering) include:
easy to separate from water as it is not readily* Gastrointestinal irritation
biodegradable. On the other hand, in air, it quickly* Liver and kidney damage and possibly liver and
evaporates and produces a vapor which has a verykidney cancer
distinct, unpleasant odor. Breathing this vapor can result* Nervous system effects ranging from hyperactivity
in discomfort as described below under symptoms.andincoordination to convulsions and unconsciousness
The National Center for Environmental Health (a* Risks to healthy fetal development
branch of the Centers for Disease Control) suggestsObviously, at the expense of the health of the general
that people who concerned about overexposure topublic, requiring oxygenating additives in gasoline has
MTBE through inhalation or water contaminationbeen a mixed blessing. Indeed, before the federal
contact a state drinking water agency immediately.government suggested the use of MTBE, and before
Potential exposure is at times identified by the stronggas and oil companies began adding it, more research
smell and may or may not be indicative of harmfulshould have been done as to its effects on the
levels. Exposure to MTBE can be confirmed becauseenvironment and human health.
it is detectable in the bloodstream, as well as breath