HEALTH-EFFECTS OF GASOLINE EXPOSURE .2. MORTALITY PATTERNS OF DISTRIBUTION WORKERS IN THE UNITED-STATES

In this study, the cohort consisted of 18,135 distribution employees w ith potential exposure to gasoline for at least one year at land-based terminals (n = 9,026) or on marine vessels (n = 9,109) between 1946 a nd 1985. The primary objective of the study was to determine the relat ionship, if any, between exposure to gasoline and mortality from kidne y cancer or leukemia. In addition, other causes of death of secondary interest included multiple myeloma and heart diseases. The mortality o f the cohort was observed through June 30, 1989. The results of this s tudy indicated that there was no increased mortality from either kidne y cancer or leukemia among marketing and marine distribution employees who were exposed to gasoline in the petroleum industry when compared to the general population. Among the land-based terminal employees, th e kidney cancer standardized mortality ratio (SMR) was 65.4 (12 deaths ) and leukemia SMR was 89.1 (27 deaths). For the marine cohort, the SM Rs were 83.7 for kidney cancer (12 deaths) and 70.0 for leukemia (16 d eaths) respectively. More importantly, based on internal comparisons, there was no association between mortality from kidney cancer or leuke mia and various indices of gasoline exposure. In particular, neither d uration of employment, duration of exposure, age at first exposure, ye ar of first of exposure, job category, cumulative exposure, frequency of peak exposures, nor average intensity of exposure had any effect on kidney cancer or leukemia mortality. For acute myeloid leukemia, a no nsignificant mortality increase was found in land-based terminal emplo yees (SMR = 150.5, 13 deaths), but no trend was detected when the data were analyzed by various gasoline exposure indices. This nonsignifica nt excess was limited to land-based terminal employees hired before 19 48. On the other hand, a deficit of mortality from acute myeloid leuke mia was observed among marine employees (SMR = 74.2, 5 deaths). For th e two cohorts combined, SMR for acute myeloid leukemia was 117.1 based on 18 deaths. We did not find any relationship in our study between g asoline exposure and mortality from multiple myeloma or heart diseases . In general, we did not find any significantly increased mortality, e ither overall or from specific causes, associated with gasoline exposu re in this study of marketing and marine distribution employees.