US EPA

3859088 

Journal Article 

Exposure of Portuguese children to the novel non-phthalate plasticizer di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate (DINCH) 

Correia-Sá, L; Schütze, A; Norberto, S; Calhau, C; Domingues, VF; Koch, HM 

2017 

1 

Environment International
ISSN: 0160-4120
EISSN: 1873-6750 

Elsevier 

OXFORD 

102 

Elsevier 

79-86 

English 

28188053 

10.1016/j.envint.2017.02.001 

WOS:000400202400010 

https://linkinghub.elsevier.com/retrieve/pii/S0160412016310017
Exit
 

Di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate (DINCH) is used as substitute for high molecular weight phthalate plasticizers such as di-(2-ethylhexyl) phthalate (DEHP) and di-(iso-nonyl) phthalate (DINP). Due to a rapid substitution process we have to assume omnipresent and increasing DINCH exposures. The aim of this study was to evaluate DINCH exposure in 112 children (4-18years old) from Portugal, divided in two groups: 1) normal-/underweight following the usual diet; and 2) obese/overweight but under strict nutritional guidance. First morning urine samples were collected during the years 2014 and 2015. Oxidized DINCH metabolites (OH-MINCH, oxo-MINCH, cx-MINCH) were analyzed after enzymatic hydrolysis via on-line HPLC-MS/MS with isotope dilution quantification. We detected DINCH metabolites in all analyzed samples. Urinary median (95th percentile) concentrations were 2.14μg/L (15.91) for OH-MINCH, followed by 1.10μg/L (7.54) for oxo-MINCH and 1.08μg/L (7.33) for cx-MINCH. We observed no significant differences between the two child-groups; only after creatinine adjustment, we found higher metabolite concentrations in the younger compared to the older children. Median (95th percentile) daily DINCH intakes were in the range of 0.37 to 0.76 (2.52 to 5.61) μg/kg body weight/day depending on calculation model and subpopulation. Body weight related daily intakes were somewhat higher in Group 1 compared to Group 2, irrespective of the calculation model. However, in terms of absolute amounts (μg/day), DINCH intakes were higher in Group 2 compared to Group 1. In regard to age, we calculated higher intakes for the younger children compared to older children, but only with the creatinine-based model. This new data for southern European, Portuguese children adds information to the scarce knowledge on DINCH, confirming omnipresent exposure and suggesting higher exposures in children than adults. Significant sources and routes of exposure have yet to be unveiled. For now, all calculated daily intakes are far below established health benchmark levels (TDI, RfD). However, rapidly increasing exposures have to be expected over the next years. 

DINCH; Exposure assessment; Human biomonitoring; Plasticizer; Portuguese children; Urinary metabolites; Anthropometry; Biomolecules; Cyclohexane; Enzymatic hydrolysis; Nutrition; Plasticizers; Reinforced plastics; Solvents; Metabolites; creatinine; di [iso nonyl]cyclohexane 1,2 dicarboxylic acid; unclassified drug; cyclohexanecarboxylic acid derivative; dicarboxylic acid; diisononyl 1,2-cyclohexanedicarboxylic acid; biomonitoring; chemical pollutant; child health; dietary intake; hydrolysis; metabolism; Article; biological monitoring; body mass; body weight; caloric intake; creatinine urine level; dilution; environmental exposure; food intake; high performance liquid chromatography; limit of detection; limit of quantitation; mass spectrometry; obesity; Portugal; Portuguese (citizen); risk assessment; room temperature; underweight; urinalysis; vegetable; adolescent; analysis; environmental monitoring; oxidation reduction reaction; preschool child; tandem mass spectrometry; Child, Preschool; Cyclohexanecarboxylic Acids; Dicarboxylic Acids; Overweight; Oxidation-Reduction; Thinness