Original article

Scand J Work Environ Health 2000;26(4):353-358    pdf


Time to pregnancy among male workers of the reinforced plastics industry in Denmark, Italy and The Netherlands

by Kolstad HA, Bisanti L, Roeleveld N, Baldi R, Bonde JP, Joffe M, ASCLEPIOS

Objectives The relationship between occupational styrene exposure and male fecundity was examined.

Methods Among 1560 Danish, Italian, and Dutch reinforced plastics workers, 220 styrene-exposed workers and 382 unexposed referents who had fathered a child were identified. A total of 768 historical styrene measurements conducted in 1970-1996 in the study companies formed the basis for semiquantitative exposure assessment in combination with measurements of urinary styrene metabolite levels. All the subjects were interviewed about work conditions and other factors potentially related to reduced fecundity. Fecundity was measured as the reported time to pregnancy (number of months a couple needed to conceive their youngest child).

Results A statistically nonsignificantly reduced fecundity was observed for the styrene-exposed workers [fecundity ratio 0.79, 95% confidence interval (95% CI) 0.59-1.05]. But no consistent pattern of a detrimental effect on fecundity was found when time to pregnancy was related to worktasks indicating higher styrene exposure levels or semiquantitative or quantitative measures of styrene exposure. The workers with high exposure showed a fecundity ratio of 1.09 (95% CI 0.69-1.72).

Conclusions It is unlikely that styrene exposure has a strong effect on male fecundity.