Prenatal exposure to organochlorine compounds and lung function during childhood.

INTRODUCTION

Prenatal exposure to organochlorine compounds (OCs) can increase the risk of reported respiratory symptoms in children. It remains unclear whether these compounds can also impact on lung function. We assessed the association between prenatal exposure to OCs and lung function during childhood.

METHODS

We included 1308 mother-child pairs enrolled in a prospective cohort study. Prenatal concentrations of p,p'-dichlorodiphenyltrichloroethane [p,p'-DDT], p,p'-dichlorodiphenyldichloroethylene [p,p'-DDE], hexachlorobenzene [HCB], and seven polychlorinated biphenyls [PCBs] were measured in cord blood. Spirometry was performed in the offspring at ages 4 (n = 636) and 7 years (n = 1192).

RESULTS

More than 80% of samples presented quantifiable levels of p,p'-DDE, HCB, PCB-138, PCB-153, and PCB-180; p,p'-DDE was the compound with the highest median concentrations. At 4 years, prenatal p,p'-DDE exposure was associated with a decrease in forced expiratory volume in 1 s (FEV) in all quartiles of exposure (e.g., third quartile [0.23-0.34 ng/mL]: β for FEV -53.61 mL, 95% CI -89.87, -17.35, vs. the lowest). Prenatal p,p'-DDE levels also decreased forced vital capacity (FVC) and FEV/FVC, but associations did not reach statistical significance in most exposure quartiles. At 7 years, p,p'-DDE was associated with a decrease in FVC and FEV in only the second quartile of exposure (e.g. β for FEV -36.96 mL, 95% CI -66.22, -7.70, vs. the lowest). Prenatal exposure to HCB was associated with decreased FVC and FEV, but in only the second quartile and at 7 years (e.g. [0.07-0.14 ng/mL]: β for FEV -25.79 mL, 95% CI -55.98, 4.39, vs. the lowest). PCBs were not consistently associated with lung function.

CONCLUSION

Prenatal exposure to p,p'-DDE may decrease lung function during childhood, especially FEV and at medium levels of exposure. Further and deeper knowledge on the impact of environmental chemicals during pregnancy on lung development is needed.