Researchers in Sweden have embarked on studies to determine whether exposure to a widely used fuel additive may be harmful in humans.
The additive, methyl tertiary butyl ether (MTBE), is mixed with gasoline during winter months to provide extra oxygen that makes fuel burn more cleanly and reduces air pollution. No data are available on the effects of MTBE in humans, but it has been shown to cause liver and kidney tumors at high exposures in rodents.
In a collaboration between the Swedish researchers and toxicologists in the United States, metabolites of MTBE were characterized in humans for the first time. In the study, four men were exposed to MTBE for 2 hours. During exposure they rode exercise bicycles and were monitored for heart rate and other vital signs every 20 seconds. Analysis of blood and urine samples with nuclear magnetic resonance spectroscopy after exposure showed that MTBE metabolites alpha-hydroxyisobutyric acid and 2-methyl-1,2-propanediol were present in the urine.
Voelker R. Fuel Additive Metabolites Probed. JAMA. 1999;282(18):1713. doi:10.1001/jama.282.18.1713-JWM90009-4-1