Levels and determinants of urinary phthalate metabolites in New Zealand children and adults

This first national biomonitoring survey of urinary phthalate metabolites in the New Zealand population aimed to provide baseline data, identify exposure determinants, and make comparisons with health-based exposure guidance values.The survey conducted in 2014-2016 involved the collection of morning-void urine from 298 children (5-18 years) and 302 adults (20-65 years), 33% of Māori ethnicity. A questionnaire collected information on demographic factors and diet. Urine was analysed for creatinine, specific gravity, and 10 phthalate metabolites through liquid chromatography tandem-mass spectrometry (MMP; MEP; MBP iso+n; MBzP; MCHP; MEHP; MEOHP; MEHHP; MCPP; and MiNP). Determinants of exposure were assessed using multivariable linear regression.Detection frequencies exceeded 95% for metabolites of DEP, DEHP and DBP. The highest GM was observed for the DBP metabolite MBP iso+n (36.1 μg/L adults; 60.5 μg/L children), followed by the sum of three DEHP metabolites (MEHP+MEOHP+MEHHP: 19.0 μg/L adults; 37.0 μg/L children), and the DEP metabolite MEP (19.1 μg/L adults; 12.0 μg/L children). For most phthalate metabolites New Zealand levels were in the mid-range of internationally reported levels, while for DEP they were in the low range. Māori and non-Māori had similar levels. Children had higher GMs than adults for most metabolites, except for MEP. A proportion of children and adults exceeded the biomonitoring equivalents of health-based guidance values for DBP (0-16% and 0-3% respectively), and DEHP (0-0.7% and 0-0.3% respectively). Eating warm meals from plastic containers ≥2 times/week was associated with higher levels of DEHP metabolites, MBP iso+n, and MBzP.Phthalate exposure is omnipresent in both children and adults in New Zealand. Exceedances of the biomonitoring equivalents for DBP and DEHP indicate that potential health effects from exposure to these phthalates cannot be excluded with sufficient certainty.