Exposure Characteristics and Cumulative Risk Assessment for Phthalates in Children Living near a Petrochemical Complex.

BACKGROUND: School-aged children living near plastics-producing factories may have higher risk of exposure to phthalates released during the manufacturing processes. OBJECTIVES: We aimed to investigate the urinary concentrations of phthalate metabolites in school-aged children living near a petrochemical complex and estimate the cumulative risk of phthalate exposure. METHODS: We used a well-established cohort (Taiwan Petrochemical Complex Cohort for Children, TPE3C) of school-aged children (6-13 years old) living near polyvinyl chloride (PVC) and vinyl chloride monomer (VCM) factories in central Taiwan from October 2013 to September 2014. A total of 257 children were included from five elementary schools: Syu-Cuo Branch (n = 58, school A, ~0.9 km), Feng-An (n = 40, school B, ~2.7 km), Ciao-Tou (n = 58, school C, ~5.5 km), Mai-Liao (n = 37, school D, ~6.9 km), and Lung-Feng (n = 57, school E, ~8.6 km). We analyzed 11 metabolites of seven phthalates (including di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DnBP)) in urine. Daily intakes (DIs) were compared with acceptable intake levels to calculate the hazard quotient (HQ) for individual phthalates, and the cumulative risk for each child was assessed using a hazard index (HI), which was the sum of the the individual HQs. RESULTS: The geometric mean and proportion of participants with HIs exceeding one for hepatic (HIhep) and reproductive (HIrep) effects were 0.33 (13.2%) and 0.24 (7.8%), respectively. The major contributors to phthalate exposure risk were DEHP, di-iso-butyl phthalate (DiBP) and DnBP in all children. Moreover, we observed a U shaped distribution of DEHP exposure by school distance from the PVC and VCM factories (school A: 7.48 µg/kg/day and school E: 80.44 µg/kg/day). This may be due to emissions (closest) and and being located downwind of PVC scrap incineration (farthest). CONCLUSIONS: Our findings suggest that children living near a petrochemical complex were at a greater risk of phthalate exposure than normal school-aged children and that phthalate exposure was mainly attributed to DEHP, DiBP and DnBP. In addition, inhalation may have been a risk factor for people living near to PVC and VCM factories.