Determination of Phthalates in Purified Drinking Water in Italy

Abstract

This study investigated the presence and concentration of selected phthalates in municipal tap waters and purified waters sourced from domestic water purifiers and municipal reverse osmosis-based supplies. Five target compounds: Diethyl phthalate (DEP), Diisobutyl phthalate (DiBP), Butyl octyl phthalate (BOP), Dibutyl phthalate (DBP), and bis(2-ethylhexyl) phthalate (DEHP) were identified and quantified in the samples using the solid-phase microextraction gas chromatography-mass spectrometry (SPME-GC/MS) method. The analytical protocol demonstrated good sensitivity, precision, and accuracy, with low limits of detection and quantification, making it suitable for routine monitoring applications. Phthalates were detected in all samples, including both inlet and treated water, highlighting their widespread occurrence. The results show a significant percentage of reduction in total phthalate concentrations (from 4% to 53%; 30% on average) in purified water samples compared to untreated inlet water, thereby indicating the potential efficacy of such systems in reducing organic pollutants. Risk assessment based on the EFSA guidelines showed that the estimated daily intakes for all detected phthalates remained well below tolerable daily intake limits for both adults and toddlers. The findings underscore the importance of monitoring phthalates in drinking water and support the implementation of regular maintenance strategies for filtration devices. The analytical approach developed may be adopted as a cost-effective tool for water quality assessment and offers promising potential for broader application in public health and commercial water treatment systems.