HEALTH-EFFECTS OF MTBE AMONG NEW-JERSEY GARAGE WORKERS

Methyl tertiary butyl ether (MTBE) is an oxygenated additive used in t he 1993 wintertime oxyfuel program to reduce tailpipe carbon monoxide emissions. Because of complaints of acute health symptoms, particularl y in the state oi Alaska, this program was terminated prematurely in t hat state. We designed a cross-sectional cohort study of self-reported symptoms of garage workers in the state of New Jersey exposed to high and low MTBE concentration environments. Two hundred and thirty-seven participants were divided into 2 groups: 115 workers in northern New Jersey sampled during the wintertime oxyfuel program, and 122 workers in southern New Jersey 10 wk alter the phase-out date for the program in that area. The outcome measures included a list of symptoms, oi whi ch some were felt to be attributable to MTBE exposure. Participants we re asked to indicate the frequency oi those symptoms they had experien ced over the last 30 days. In addition, workers were given identical p reshift and postshift questionnaires and asked to rank any discomfort they were experiencing al that time from a list of symptoms. In compar ing all garage workers in northern New Jersey (high exposure) to those in southern New Jersey (low exposure), no differences were found in t he reporting of symptom frequency over the last 30 days. In the pre-/p ostshift questionnaire analysis, both groups felt significantly worse by the end oi the work day, but there was no difference between the gr oups across the work shift. In comparing fuelers who pump gasoline mor e than 5 h/day, again no differences were found in the reporting of sy mptom frequency over the last 30 days. In the pre/postshift analysis, however, the northern group reported a significantly increased number of symptoms, but again no difference was found between the groups acro ss the workshift. Because the fuelers in the north were on average 15 yr older than those in the south, this same analysis was repeated with fuelers in the north and age-, sex-, and education-matched controls i n the south. In this analysis, no group differences in symptom reporti ng were seen. In summary, no untoward health effects clearly attributa ble to MTBE exposure could be demonstrated in this cohort of healthy g arage workers.