RESUMO
Placenta and umbilical cord blood are important media for investigating maternal-fetal exposure to environmental pollutants. Historically hexachlorocyclohexanes (HCHs) were once widely-used in China. In this study, residues of HCHs were measured in placenta and umbilical cord blood samples for 40 women from Beijing. The measured median values of HCHs were 62.0 and 68.8 ng/g fat in placenta and umbilical cord blood, respectively. Concentrations of HCHs in placenta and umbilical cord blood of urban cohort were higher than those of rural group due to enhanced consumption of fish, meat, and milk. Residues of HCHs in placenta were significantly correlated with total food consumption, dietary intake, and maternal age, and could be predicted using the parameters dependent upon ingestion of meat and milk. The transplacental exposure of fetuses to HCHs was revealed by a close association between the residual levels in the paired placenta and the paired umbilical cord blood samples.
Assuntos
Dieta/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Sangue Fetal/metabolismo , Hexaclorocicloexano/metabolismo , Exposição Materna/estatística & dados numéricos , Placenta/metabolismo , Adulto , China , Monitoramento Ambiental , Poluentes Ambientais/sangue , Feminino , Hexaclorocicloexano/sangue , Humanos , GravidezRESUMO
The temporal trends in daily dietary exposure of the populations in Beijing and Shenyang, China to DDTs and HCHs through consumption of various food categories and the associated health risks were investigated in this work. The estimated dietary intakes of DDTs and HCHs in 2005/2007 were almost one and two orders of magnitude lower than those in 1992 and in the 1970s, respectively, revealing the historical decrease of DDT and HCH in Chinese foods after their applications were banned. The relative contributions of different foodstuffs to the overall intakes of DDTs and HCHs in the 1970s and in 1992 were very different from those in 2005/2007, mainly due to the remarkable concentration variance in foodstuffs and changes in diet habit of population. According to the hazard guidelines, it is concluded that intakes of these two pesticides in 2005/2007 may not exert adverse effects on human health.