Study On The Metabolite Levels Of Phthalates In Cord Serum And Its Influence Factors

ObjectivePhthalates are a family of industrial chemicals that have been used for a variety of purposes, such as plasticizers that impart flexibility and durability to polyvinyl chloride (PVC) products. Many phthalates are kinds of known environmental endocrine disruptors, can affect the normal endocrine activities of humans and animals, which will cause potential adverse effects on reproduction and development. In recent years, with the rapid increase of industry, phthalates are produced in extremely large volumes, and constantly released into the environment through a variety of channels, has become one of the most common pollutants worldwide. Human can exposure to PAEs through many routes. The objective of this study is to detecte the concentrations of5phthalates metabolites in cord serum and evaluate the levels of fetus expose to PAEs through the pregnant mother. Combining the date collected from questionnaire and cord serum measurement results, preliminary analyzing the possible factors influencing fetus exposure to PAEs through the pregnant mother, provide method to prevent fetus exposure to PAEs through the pregnant mother.MethodsIn this study, we recruited96pregnant women in Tianjin, excluded the occupational exposure history and disease history. We collected the cord blood during childbirth; SPE-HPLC-MS were used to determine the concentration of5phthalates metabolites in cord serum. All the participators were asked to complete a questionnaire; the epidemiological results and measurement date were evaluated by ordinal Logistic regression of Windows SPSS17.0.Results(1) This study were optimised the method of detecting the concentration of5phthalates metabolites in cord serum. The cord serum was de-conjugated by adding β-glucuronidase. Cord serum proteins were removed by phosphoric acid and organic solvent (acetonitrile), eliminate the interference caused by protein. After enzymatic treatment, the samples were subjected to the solid phase extraction column to clean-up and concentrate. The contents of the5kinds of phthalates metabolites were determined using HPLC-MS. The limits of detection ranged from0.109μg/L to0.579μg/L, the average recovery rates were80.59%-85.75%, and the relative standard deviation were3.09%-3.91%.(2) The detectable rates of MMP, MEP, MBP, MBzP and MEHP in96cord serum samples were98.96%,94.79%,79.17%,93.75%,98.96%, the medians and P25-P75were26.92μg/L (12.50μg/L-59.13μg/L),11.99μg/L (3.55μg/L-29.84μg/L),16.97μg/L (4.03μg/L-40.43μg/L),3.23μg/L (0.97μg/L-6.76μg/L),5.48μg/L (3.52μg/L-8.25μg/L) respectively.(3) Analyzing the possible influencing factors on pregnant exposure to PAEs in pregnancy. Hair perm was the possible influencing factor of DEP(OR=3.28,95%CI:1.55-6.95), BBP(OR=4.79,95%CI:2.23-10.03); using plastic cup was the possible influencing factor of DEHP(OR=2.66,95%CI:1.21-5.85).ConclusionThis study has successfully optimized HPLC-MS to determine the level of PAEs in cord serum. From the result, we can find that PAEs has detected in most cord serum samples, indicated that fetus extensivly expose to PAEs through the pregnant mother. We have analyzed possible influencing factors on pregnant exposure to PAEs in pregnancy. Hair perm was the possible influencing factor of DEP, using plastic products was the possible influencing factor of DEHP.