MTBE, or methyl tertiary butyl ether, is a gasoline additive that was widely introduced in the 1990s to help refiners comply with clean-air standards. Unfortunately, MTBE is highly water soluble, meaning that leaks from underground gasoline tanks spread quickly to water supplies, where it can persist for decades. In addition to making drinking water smell and taste like turpentine, MTBE has been shown to cause cancer in laboratory animals when inhaled; the federal Environmental Protection Agency has said that it is a likely carcinogen in drinking water as well. It is also expensive to remove; the Association for Environmental Health and Sciences has determined that cleaning up all U.S. contamination would cost between $1 billion and $3 billion. 25 states have passed legislation banning or limiting the sale of MTBE.
MTBE – Methyl Tertiary-Butyl Ether – And Who Is At Risk
According to the National Institute for Occupational Safety and Health (NIOSH), the following are the occupations which are the most susceptible to conditions of dangerous exposure to Methyl tertiary-butyl ether (MTBE) one of various additives used to oxygenate gasoline:
• Gas Station Attendants
• Taxi drivers
• Bus drivers
• Delivery drivers
• Gasoline processing plant employees
• Others with high exposures to oxyfuels
However, those with occupations which bring them into abnormally high levels of contact with gasoline in urban areas are not the only people at risk. Brief exposure when refueling a vehicle or while commuting may also present danger. A further risk is the unknowing consumption of water from contaminated water supplies. The EPA has issued guidelines recommending that, to protect children, drinking water levels of MTBE not exceed 4 milligrams per liter of water (4 mg/L) for an exposure of 1-10 days, and 3 mg/L for longer-term exposures.
The American Conference of Governmental Industrial Hygienists (ACGIH) has recommended an exposure limit of 40 parts of MTBE per million parts of air (40 ppm) for an 8-hour work day/40-hour work week. If one has concerns or reservation about the drinking water in a particular area or levels of MTBE at work, it is prudent to contact a local health authority and/or take a sample of the questionable water to be analyzed for dangerous content. This is especially recommended in gasoline high traffic areas, such as near gas stations, processing plants or storage facilities. Fortunately, there is no reason to be concerned about exposure to MTBE under any other circumstances than as an additive to gasoline, as it is not used for any other purposes. One minor exception to this is in the rare and extreme cases in which doctors use MTBE to dissolve gallstones.
Complaints regarding MTBE contamination or health risks fall under the category of toxic tort. Tort law requires the arguments of the plaintiff to be more persuasive than those of the defendant for damages to be awarded. Cases regarding MTBE have gone to court and the plaintiffs have successfully received damages for ailments relating to the exposure to MTBE.
In these cases it has been proven that companies have shirked responsibility and duty to warn consumers of the potential dangers of a product, or have been guilty of knowingly selling a defective product. There are many approaches which can be taken to toxic tort litigation, and many reasons that the responsible parties may be held accountable for lack of due concern for public safety and the environment. Fortunately, legitimate recourse for people who have suffered pain or discomfort because of exposure to the dangerous additive MTBE is available.
MTBE – Methyl Tertiary-Butyl Ether
Methyl tertiary-butyl ether (MTBE) is one of various additives used to oxygenate gasoline. These substances are blended with gasoline to reduce carbon dioxide emissions (MTBE also reduces other toxic chemical compounds in vehicle emissions). MTBE has been in use since 1979, primarily in response to the diminishing use of lead in gasoline.
In 1990, with the passage of the Clean Air Act Amendments (specifically Section 211), the use of oxygenated gas was required in areas with excessive levels of CO air pollution. These areas were primarily urban, meaning that huge numbers of individuals have been exposed to MTBE. The positive aspect of the blend of gasoline and MTBE (which is highly flammable) is that it allows a much cleaner burn and less environmentally harmful emissions. Of the reformulated gasoline (RFG) mandated by this act, over 85% contain MTBE.
According to the Environmental Protection Agency (EPA), although the use of MTBE appears noble, its use has caused many health and safety concerns for people who are exposed to it. Not only can individuals suffer health risks by inhaling MTBE, but the contamination of potable water stores, and thus ingestion, are other very real concerns. Water contamination can happen through the leakage from gasoline storage or transport units, most of which are located underground. MTBE has a very high level of solubility and there have been many incidences of water contamination all over the country, especially in places of high population density (such as California and New England). While MTBE is absorbed quickly into water, it is not similarly easy to separate from water as it is not readily biodegradable. On the other hand, in air, it quickly evaporates and produces a vapor which has a very distinct, unpleasant odor. Breathing this vapor can result in discomfort as described below under symptoms.
The National Center for Environmental Health (a branch of the Centers for Disease Control) suggests that people who concerned about overexposure to MTBE through inhalation or water contamination contact a state drinking water agency immediately. Potential exposure is at times identified by the strong smell and may or may not be indicative of harmful levels. Exposure to MTBE can be confirmed because it is detectable in the bloodstream, as well as breath and urine, for up to two days after contact.
While not considered as dangerous as Benzene (an element that MTBE replaces in gasoline) MTBE is a carcinogen at high enough exposure levels, as shown by laboratory experiments on animals conducted by the CDC. However, no governmental bodies have claimed to find sufficient evidence to recognize MTBE as a possible human carcinogen. Part of this reasoning is that it is eventually broken down and removed from the body, thus long term accumulation is not a risk. Since humans do not encounter MTBE as a separate entity from gasoline, very few concrete conclusions have been drawn since a causal relationship cannot be adequately established between the chemical and health conditions.
Specifically, the Agency for Toxic Substances and Disease Registry (ATSDR) has still reserved a definitive judgment on the adverse health effects of MTBE. Many other studies have been conducted though and indicate that the following are symptoms found after contact with MTBE.
Symptoms from inhalation include:
• Nose or throat burning
• Other respiratory irritation
• Eye irritation
• Dizziness, “spaciness” or disorientation
Possible health issues resulting from ingestion or dermal contact (i.e. drinking, swimming or showering) include:
• Gastrointestinal irritation
• Liver and kidney damage and possibly liver and kidney cancer
• Nervous system effects ranging from hyperactivity and incoordination to convulsions and unconsciousness
• Risks to healthy fetal development