Mortality patterns among styrene‐exposed boatbuilders

Abstract

In order to test the hypothesis that leukemia and lymphoma may be associated with exposure to styrene, cause-of-death patterns were studied at two reinforced plastic boatbuilding facilities. There were 5,021 workers who met the criterion of having worked at the two plants between 1959 and 1978. Based on industrial hygiene surveys conducted at the two plants, 2,060 individuals were determined to have worked in departments classified as having high exposure to styrene. There were 176 deaths observed among the total cohort, in comparison to 195.3 deaths expected (standardized mortality ratio [SMR] = 90). Among the high styrene exposure group, 47 deaths were observed in comparison to 41.5 deaths expected (SMR = 113). No leukemia or lymphoma deaths were observed in either the high exposure group or the total cohort. An excess of accidental deaths among the high exposure group (18 observed vs 12.4 expected) did not appear to be due to styrene's acute central nervous system effects, since none of the individuals were employed at the facilities at the time of their death. However, the possibility of a chronic effect could not be dismissed. While leukemia and lymphoma did not appear to be related to styrene exposure, the study had little statistical power to detect excesses of these diseases, due to the short length of observation and the young age of most cohort members. It was concluded that the cohort should provide increasingly useful information on chronic styrene toxicity as the population ages and the observation period increases.

Mortality of workers exposed to styrene in the manufacture of glass-reinforced plastics.

“…Our estimates of the exposure levels associated with this occupation were based upon measurements made since 1975 at five of the eight factories studied, and they are in broad agreement with those which have been found in similar 2 circumstances by other investigators (10,12,13,15). There is no reason to believe that work conditions were better in the earlier years of the study period or at the factories for which no hygiene data were available.…”

“…The apparent discrepancy between this finding and the positive results of some previous studies may be a chance effect, but it could also be due to unrecognized confounding exposures in the chemical and plastics industries. In the only other reported survey of mortality among glass-reinforced plastics workers (10), no cases of lymphoma or leukemia were found.…”

Mortality among workers engaged in the development or manufacture of styrene-based products--an update.

“…but different, industries are important to consider. Table 8 summarizes seven published mortality studies (7)(8)(9)(10)(11)(12)(13) of workers who were potentially exposed to styrene-based products in the three general industry classifications of styrene-butadiene rubber, styrene monomer and polymerization, and reinforced plastics. It is critical to differentiate the exposure circumstances in each of these industrie s before consider ing their individual or collective results.…”

The non-Hodgkin lymphomas: A review of the epidemiologic literature

“…[218][219][220][221][222][223][224] Sathiakumar et al 220 reported no association with NHL mortality among styrene-butadiene rubber workers employed in the North-American synthetic rubber industry (SMR 5 1.00, 95% CI: 0.75-1.30). Among rubber industry workers at the same plants, Graff et al 225 reported nonsignificant positive associations with the 4 highest categories of styrene exposure, and nonsignificant inverse associations with the 3 highest categories of butadiene exposure.…”