Abstract:
[Objective] To evaluate exposure levels of phthalates and its influencing factors in infants at the age of 2 years old.
[Methods] Questionnaires and spot urine samples were collected from 344 2-year-old infants in a county of Jiangsu Province from June 2011 to January 2012. The survey content included infants' general information and their behaviors & habits with potential exposure to phthalates. Nine urinary phthalate metabolites were determined by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Non-parametric test and multiple linear regression analysis were used to identify the influencing factors of infant phthalates exposure.
[Results] The phthalate metabolites were identified in all urine samples of these infants. The median levels were as follows: monomethyl phthalate (MMP), 15.73 μg/L; monoethyl phthalate (MEP), 13.99 μg/L; monobutyl phthalate (MBP), 39.30 μg/L; monoisobutyl phthalate (MiBP), 29.23μg/L; mono-3-carboxypropyl phthalate (MCPP), 2.90 μg/L; mono-2-ethylhexyl phthalate (MEHP), 2.88 μg/L; mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), 11.93 μg/L; mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), 8.70 μg/L, and mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), 50.10 μg/L. The positive rates were 100.00% for MMP, MEHHP, and MECPP, respectively; 89.80% for MEHP; and 96.80%-99.71% for the other 5 metabolites. The usage of plastic milk bottles or plastic tableware was found to have statistically significant effects on concentrations of some urinary phthalate metabolites in infants' urine samples (P < 0.05).
[Conclusion] The findings suggest that the infants are widely exposed to phthalates. The usage of plastic milk bottles or plastic tableware might increase infants' exposure to phthalates.