Environmental Endocrine Disruptors And Low Birth Weight In Newborns: A Case-control Study In Shanghai

Low birth weight(LBW) is the first contributor of the increased mortality of newborns during the first year,and plays an important role in children disease burden. LBW is associated with development problems in childhood and the risk of various diseases in adulthood.Besides maternal nutrition and social-economic status, environmental endocrine disruptors(EEDs) are recently considered as one of the important risk factors in the development of LBW.EEDs are exogenous materials or mixtures that could change the endocrine functions and cause adverse health outcomes in individuals,offspring or population.Two kinds of commonly-exposed EEDs are phthalates and surfactants for humans.Those chemicals are ubiquitous in the environment and can be accumulated through food chain.Human might expose to them through various pathways and eventually be affected by EEDs,especially during development.Recently,umbilical cord blood and meconium are considered as eligible biomatrixes on research of environment related diseases in children.Those specimens will provide detailed information of fetal exposure to various xenobiotics or substances taken during maternal pregnancy,which will be useful to health-based risk assessment of chemicals.This study is aimed to explore the potential risk factors of LBW in the term newborns in Shanghai by a case-control study.Two kinds of EEDs,phthalates and surfactants,have been shown that they are related to LBW confirmed in animal experiments.Thus,concentrations of phthalates and surfactants in umbilical cord blood and meconium samples collected from newborns are measured in the present study by using SPE-HPLC method.The purpose of this study is to investigate whether whether higher concentrations of phthalates or surfactants exist in low birth weight newborns,comparing with normal birth weight newborns.88 term low birth weight singletons,whose birth weight were less than 2500g and gestational weeks were more than 37 weeks,were chosen as the cases.And 113 normal singletons,whose birth weight were more than 2500g and gestational weeks were more than 37 weeks,were matched as the controls.The mean birth weight and the birth length of the cases were 2285.75±220.00g and 45.33±2.42cm,respectively, whereas those of the controls were 3346.65±421.78g and 48.81±1.45cm,respectively. Results of the multiple Logistic regression analysis showed that,abnormality of umbilical cord and dysmenorrhea were significantly related to LBW(P＜0.05).Results of phthalates and surfactants concentrations in cord blood and meconium samples showed that those two chemicals could be detected in most samples of newborns. Phthalates levels were higher than surfactants in cord blood and meconium.There are significantly higher levels of EEDs in meconium in low birth weight newborns than those of controls(P＜0.05).Significant correlations were found between DBP,MEHP and 4-NP concentrations in cord blood and LBW in newborns.There was a significant association between newborns' birth weight and the levels of MBP and MEHP in meconium samples.Those results suggested that phthalates and surfactants are one of the environmental risk factors of LBW.