Gestational Triclosan Exposure and Infant Birth Weight: A Systematic Review and Meta-analysis

Abstract

Background/Aim: Exposure to triclosan, an antimicrobial chemical used in personal care and cleaning products, has been associated with reduced birth weight in some, but not all studies. Thus, we conducted a systematic review and meta-analysis to characterize the relation of gestational triclosan exposure with infant birth weight, and identify potential sources of heterogeneity between studies. Methods: We identified original studies that measured maternal urinary triclosan concentrations during pregnancy and reported their association with infant birth weight. We considered birth weight, which we further characterized based on adjustment for gestational age or gestational age standardized birth weight z-scores. Using a random effects model, we estimated differences in these outcomes per 10-fold increase in triclosan concentrations. Results: Among thirteen identified studies, the range of median triclosan concentrations varied by approximately 2 orders of magnitude (0.6 to 29 ng/mL), with higher concentrations in North American and most European studies compared to Asian ones. Associations between triclosan and birth weight (β: -41g; 95% CI: -110, -28; n=4) were stronger than those when birth weight was adjusted for gestational age (β: -16g; 95% CI: -24, -8; n=8). Similarly, increasing triclosan was associated with modest decreases in birth weight z-scores (β: -0.08; 95% CI: -0.22, 0.07; n=4). The association between triclosan and gestational age adjusted birth weight was stronger in studies with higher median triclosan values >10ng/mL compared to studies with median values <10 ng/mL (β: -27g; 95% CI: -61, 7; n=3 vs. β: 6g; 95% CI: -20, 31; n=5). Conclusion: We observed that the association of urinary triclosan concentrations with birth weight varied by adjustment for gestational age and study-specific urinary triclosan concentrations. Our results suggest that urinary triclosan concentrations are associated with lower infant birth weight in populations with higher degrees of exposure prevalence.