Persistent organic pollutants in human milk in women from urban and rural areas in northern China

Human milk specimens from 55 women in Shijiazhuang urban and Tangshan rural areas in Hebei Province in northern China were collected and analyzed for persistent organic pollutants, such as p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE), hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), and dioxins. We administered a questionnaire to milk donors at collection time, asking about lifestyle factors that potentially influence organochlorine pesticide (OCP) levels in human milk. We found that the concentrations of p,p′-DDE and β-HCH in human milk from the primiparous mothers in Shijiazhuang (3330 and 108.8 ng/g fat, respectively) were higher than in samples from mothers from Tangshan (1916 and 21.2 ng/g fat, respectively). In addition, we found the level of p,p′-DDE correlated positively with a dietary history of meat consumption or consumption of internal organs of pigs and sheep (r=0.38 and r=0.52, respectively), but not with intake frequencies of vegetables and fruits in primiparous mothers. The higher level for p,p′-DDE may be due to a greater intake of contaminated fatty foods in the industrialized areas. We also showed that the body burden of p,p′-DDE was higher in the urban group compared to the values in other regions in China after 1998. However, there was no difference in dioxin levels between the two regions. Comprehensive monitoring of persistent organic pollutants in human milk and food is needed in China.