MTBE, methyl tertiary butyl ether, is a well-known chemical to most OCAW oil workers. More than 7,000 members at 11 locations across the country produce this gasoline additive. Several thousand more work in MTBE marketing and transportation. Overall, we have 35,000 members producing gasoline.
MTBE is produced out of isobutylene and methanol on catalytic cracking units. It is one of the most commonly used additives for decreasing carbon monoxide pollution by increasing the amount of oxygen in gasoline.
It has been used in small amounts in super gasoline since 1976 when it was introduced as an octane enhancer. Demand soared after the Clean Air Act amendments of 1990 were approved by Congress. The Act mandated the use of oxygenated fuel wherever the EPA says carbon monoxide pollution is a problem, but only for the four coldest months of the year. Combustion is less efficient in cold weather, so more carbon monoxide forms, and the colder, heavier air keeps it close to the ground.
Congress gave oil companies a choice on additives: They could oxygenate their gasoline with MTBE or ethanol, an alcohol-based additive derived largely from corn. In most parts of the country, the oil companies chose their own additive, MTBE.
In New Jersey, concerned citizens formed Oxy-Busters, a group devoted to banning MTBE from gasoline in New Jersey. The group circulated a petition signed by almost 16,000 people suffering from the same symptoms as the people in Alaska. A bill to ban MTBE has been introduced in the State Assembly. North Carolina is also considering a ban on MTBE. According to a state toxicologist, there may be no advantage to MTBE's use (that is, it does not decrease carbon monoxide emissions) and it may pose risks to workers and consumers alike. He argues that MTBE should be classified as a possible human carcinogen.
Other states reporting adverse health reactions include Montana, Illinois, Arizona, Iowa, New York, Colorado, Maine, Massachusetts, and Pennsylvania.
The majority of workers surveyed suffer from numerous neurological and respiratory complaints. These include headaches, lightheadedness, anxiety, inability to concentrate, insomnia, depression, poor memory, sinus problems, irritability, ear/nose/throat complaints, fatigue, nausea, sneezing problems, shortness of breath and others. These findings are consistent with those reported by individuals exposed to MTBE fuels in Alaska. These results are still considered preliminary, but it is clear that exposure to MTBE and gasoline presents neurological and respiratory risks. (See summary below.)
In March 1995, OCAW's Alice Hamilton College hosted a one-day international conference on MTBE. Scientists, public health professionals, and others with an interest in MTBE gathered to hear up-to-date news on health effects of MTBE.
Dr. Cesare Maltoni from Bologna, Italy, presented the results of a study of nearly 2,000 rats fed MTBE in their diet. Rats fed the MTBE developed testicular and kidney cancers, leukemias and lymphomas.
The Maltoni study concluded that since these results were noted in experimental animals, MTBE must be considered as a potential human carcinogen, and its use constitutes a worldwide problem of public health.
Dr. Myron Mehlman, professor at the Robert Wood Johnson medical school and national expert on MTBE, has petitioned the EPA to classify MTBE as a probable human carcinogen. His petition stated the accepted cancer theory that a substance which causes cancer in significant numbers of experimental animals will cause cancer in humans.
But the oil industry and the Environmental Protection Agency feel that MTBE is less of a threat than other chemicals in gasoline such as benzene.
EPA's position is that oxygenated fuels - regardless of whether the oxygenation agent is MTBE or another product - are helping to clean the air and protect public health.
It is on the question of risk versus benefit that opinion is sharply divided. Some say that carbon monoxide concentrations in the air are not significantly reduced, if at all, through the use of MTBE. Others say that the threat of MTBE is a greater health threat than that posed by carbon monoxide.
Further, carbon monoxide levels during the MTBE season and after showed no difference. MTBE was not reducing carbon monoxide levels in North Carolina.
A study conducted for Colorado concluded that the use of oxygenated fuel in downtown Denver has had no statistically significant effect on atmospheric carbon monoxide concentrations and may actually increase levels of other pollutants, such as formaldehyde.
There was a strong downward trend in atmospheric carbon monoxide from 1981-91, mostly before oxygenates came into use, because of the replacement of old cars by new ones with cleaner-burning engines.
This conclusion is supported by a report issued by a consulting firm retained by Colorado. It said that the limited benefits from oxygenated fuels are decreasing as the average emissions from new cars decrease, and will continue to decrease, as new cars replace older cars.
Other presentations at the conference focused on metabolites of MTBE such as tertiary butyl alcohol and formaldehyde as well as benzene, gasoline, and automobile emissions.
MTBE has been studied in two animal species, the rat and mouse, and has been found to cause liver, kidney, and testicular tumors.
The OSHA cancer policy calls for a substance to be classified as a Category I Potential Carcinogen if it causes cancers in two similar animal studies.
MTBE falls into Category I which calls for an OSHA standard containing the following elements:
2. Ask your employer to establish a plant permissible exposure level of one ppm for MTBE.
3. Conduct a health symptoms survey for MTBE. Request a copy of a model survey from the Health and Safety Department.
4. Request that your employer institute a cancer standard for MTBE. Use the guidelines in this article as a model.
Raw (# surveyed) 105 Complaints of odor 62 59.0% Headache 60 57.1% Sinus problems 55 52.4% Ear/nose/throat complaints 55 52.4% Feeling sick 49 46.7% Lightheadedness 48 45.7% Fatigue 43 40.7% Shortness of breath 37 35.3% Breathing problems 35 33.3% Irritability 34 32.4% Sneezing problems 33 31.4% Trouble sleeping 32 30.5% Sore throat/cough 31 29.5% Increased secretion of tears/saliva/mucus 30 28.6% Inability to concentrate 27 25.7% Anxiety 22 20.9% Depression 21 20.0% Insomnia 20 19.0% Poor memory 19 18.1% Loss of appetite 13 12.4% Bronchitis 13 12.4% Stomach cramps 11 10.4% Pain on breathing 9 8.5% Average age (yrs) 42