摘要
Data on the presence of organophosphate esters(OPEs)in drinking water and its significance as a pathway of exposure are limited.In this study,we measure for the first time,concentrations of eight OPEs in 50 UK drinking water samples.Arithmetic mean concentrations of ∑8OPEs were:6.4 and 11 ng/L in bottled(n=25)and tap water samples(n=25),respectively.Concentrations of ∑8OPEs in tap water(mean:11 ng/L)exceed significantly those in bottled water(mean:6.4 ng/L)(p˂0.01).Moreover,UK tap water is more contaminated with chlorinated,aryl-,and alkyl-OPEs than bottled water.The predominant OPEs detected were:tris(butoxyethyl)phosphate(TBOEP),tris(2-chloroethyl)phosphate(TCEP),and tris(2-chloroisopropyl)phosphate(TCIPP)with arithmetic mean concentrations in the two water sample types ranging between(3.5e3.8 ng/L),(0.60-3.0 ng/L),and(1.02-2.9 ng/L),respectively.Estimated daily intakes(EDIs)(mean and high-end exposure)via drinking water for different sectors of the UK population were:infants(0.93 and 6.4 ng/kg bw/day)˃toddlers(0.46 and 3.1 ng/kg bw/day)˃children(0.35 and 2.3 ng/kg bw/day)˃adults(0.28 and 2.1 ng/kg bw/day).Based on these data,exposure to ∑8OPEs via drinking water is much lower than via:food,indoor dust ingestion,inhalation,and dermal uptake for adults and toddlers.Reassuringly,our EDIs were lower than relevant reference dose(RfD)values.However,combining our drinking water ingestion data with exposure via other pathways revealed overall exposure to 2-ethylhexyl diphenyl phosphate(EHDPP)and TCIPP to approach health-based limit values for UK toddlers under a high-end exposure scenario.
