Maternal occupational exposure to chemical substances and the risk of infants small-for-gestational-age

Background The association between maternal occupational exposure to specif ic chemical substances (organic solvents, carbon tetrachloride, herbicides, chlorophenols, polychlorinated biphenyls, aromatic amines, lead and lead c ompounds, mercury and mercury compounds) and birth of small-for-gestational -age (SGA) infants was evaluated using data from a prospective cohort study of 3,946 pregnant women in West Germany from 1987 to 1988. Methods Occupational, medical, and psychosocial information was gathered th rough a questionnaire from pregnant women who were recruited between 15 and 28 gestational weeks. Exposure to chemical substances at the current workp lace was assessed by a job-exposure matrix constructed by Pannett in 1985 a nd weighted for the number of working hours per week. Women not working at the time of the interview, women with multiple births, and women with still births were excluded from analysis. Data were analyzed using dichotomous an d polytomous logistic regression to control for age, smoking status, alcoho l consumption, body mass index, and number of former births. Results The results of the dichotomous logistic regression analysis suggest that leather work might be associated with the birth of infants small-for- gestational-age through exposure to chlorophenols (P = 0.02) and aromatic a mines (P = 0.05). In the polytomous logistic regression analysis, only the association between exposure to mercury and growth retardation reached stat istical significance (P = 0.02); however the power of the study is limited Further adjustment for income, shift work, and heavy physical work had no s ubstantial effect on the results. Conclusions These findings suggest that maternal exposure to specific chemi cals at work may be a risk factor for the birth of SGA infants. Am. J. Ind. Med. 36:213-222, 1999. (C) 1999 Wiley-Liss, Inc.