Co-exposure to polycyclic aromatic hydrocarbons and phthalates and their associations with oxidative stress damage in school children from South China.

• Mean urinary levels of mPAEs were higher than that of OH-PAHs (310 vs. 4.57 ng/mL). • Urinary OH-PAHs and mPAEs did not correlated with gender and ages. • Urinary concentrations of OH-PAHs and mPAEs have significant geographical difference. • OH-PAHs could result over 65 times higher risks of DNA damage than mPAEs. • Children in Shenzhen were subjected to non-carcinogenic risks from PAEs but not PAHs. Monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs), phthalate metabolites (mPAEs), and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in the urine of school children aged 8–11 years from Shenzhen, China were measured in order to investigate oxidative stress damage from co-exposure to PAHs and PAEs. The concentrations of OH-PAHs and mPAEs in urine were 0.36–36.5 (median: 3.86) and 9.48–1609 (median: 240) ng/mL respectively. Gender and age did not influence urinary concentrations of ΣOH-PAHs and ΣmPAEs, but geographical variations (i.e., urban versus suburban) were observed. Levels of 8-OHdG were positively correlated with urinary OH-PAHs and mPAEs, with correlation coefficients (r) varying between 0.160 and 0.365 (p < 0.05). OH-PAHs made a greater contribution to oxidative DNA damage than mPAEs when these two types of pollutants were present at the same concentrations. Human health risks were assessed using the hazard quotient and the hazard index for the cumulative risk of a complex of chemicals. The results demonstrated that risks from PAHs could be neglected, but that 29.5 % of school children may be subject to obvious health risks from PAEs, especially diethylhexyl phthalate. [ABSTRACT FROM AUTHOR]