Biomonitoring of phthalate metabolites in the Canadian population through the Canadian Health Measures Survey (2007-2009)

Abstract

Human exposure to phthalates occurs through multiple sources and pathways. In the Canadian Health Measures Survey 2007-2009, 11 phthalate metabolites, namely, MMP, MEP, MnBP, MBzP, MCHP, MCPP, MEHP, MEOHP, MEHHP, MnOP, and MiNP were measured in urine samples of 6-49 year old survey respondents (n=3236). The phthalate metabolites biomonitoring data from this nationally-representative Canadian survey are presented here. The metabolites MEP, MnBP, MBzP, MCPP, MEHP, MEOHP and MEHHP were detected in >90% of Canadians while MMP, MCHP, MnOP and MiNP were detected in <20% of the Canadian population. Step-wise regression analyses were carried out to identify important predictors of volumetric concentrations (μg/L) of the metabolites in the general population. Individual multiple regression models with covariates age, sex, creatinine, fasting status, and the interaction terms age×creatinine, age×sex and fasting status×creatinine were constructed for MEP, MnBP, MBzP, MCPP, MEHP, MEOHP and MEHHP. The least square geometric mean (LSGM) estimates for volumetric concentration (μg/L) of the metabolites derived from respective regression models were used to assess the patterns in the metabolite concentrations among population sub-groups. The results indicate that children had significantly higher urinary concentrations of MnBP, MBzP, MEHP, MEHHP, MEOHP and MCPP than adolescents and adults. Moreover, MEP, MBzP, MnBP and MEOHP concentrations in females were significantly higher than in males. We observed that fasting status significantly affects the concentrations of MEHP, MEHHP, MEOHP, and MCPP metabolites analyzed in this study. Moreover, our results indicate that the sampling time could affect the DEHP metabolite concentrations in the general Canadian population.

Keywords: BBzP; Canadian Health Measures Survey; Canadian population; Chemical surveillance; DCHP; DEHA; DEHP; DEP; DMP; DiNCH; DiNP; DnBP; DnOP; Human biomonitoring; MBzP; MCHP; MCPP; MEHHP; MEHP; MEOHP; MEP; MMP; MiBP; MiDP; MiNP; MnBP; MnOP; PVC; Phthalates; TETM; UPLC–MS–MS; Urinary metabolites; butyl benzyl phthalate; di(2-ethylhexyl) phthalate; di(ethylhexyl) adipate; di(isononyl) phthalate; di(isononyl)cyclohexane-1,2-dicarboxylate; di(n-butyl) phthalate; di(n-octyl) phthalate; dicyclohexyl phthalate; diethyl phthalate; dimethyl phthalate; mono-(2-ethyl-5-hydroxyhexyl) phthalate; mono-(2-ethyl-5-oxohexyl) phthalate; mono-2-ethylhexyl phthalate; mono-3-carboxylpropyl phthalate; mono-iso-butyl phthalate; mono-n-butyl phthalate; mono-n-octyl phthalate; monobenzyl phthalate; monocyclohexyl phthalate; monoethyl phthalate; monoisodecyl phthalate; monoisononyl phthalate; monomethyl phthalate; polyvinyl chloride; tri (2-ethylhexyl) trimellitate; ultrahigh pressure liquid chromatography–tandem mass spectrometry.