Method development using chemometric tools for determination of endocrine-disrupting chemicals in bottled mineral waters

A simple method was developed to determine 14 endocrine-disrupting chemicals (EDCs) in bottled waters, based on dispersive micro-solid phase extraction (d-mu-SPE) and liquid chromatography-mass spectrometry (LC-MS). Extraction was optimized using 2 k(-1) factorial and Doehlert experimental designs. Optimized conditions were 80 mg C18, 25 min extraction at 1000 rpm, and 6 min desorption time. Repeatability was below 17 % for all EDCs. LOD and LOQ varied from 1.60 ng L-1 (estradiol, E2) to 23.2 ng L-1 (dimethylphthalate, DMP) and from 5.33 ng L-1 (E2) to 77.3 ng L-1 (DMP). We found DMP and bisphenol A (BPA) in samples after the heat treatment. DMP was up to 58.7 mu g L-1, while BPA was up to 1.34 mu g L-1. Tolerance of daily intake (TDI) for DMP were 2.50-2.94 mu g kg(-1) day(-1) (children) and 1.43-1.68 mu g kg(-1) day(-1) (adults). TDI for BPA were 0.03-0.07 mu g kg(-1) day(-1) (children) and 0.01-0.04 mu g kg(-1) day(-1) (adults).

Automated summary

A simple method based on d-mu-SPE and LC-MS was developed to determine 14 EDCs in bottled waters. DMP and BPA were found in samples, with concentrations exceeding safe intake limits.