Novel miniaturized passive sampling devices based on liquid phase microextraction equipped with cellulose-grafted membranes for the environmental monitoring of phthalic acid esters in natural waters

Abstract

Phthalic acid esters (PAEs) are considered endocrine disruptors and potential carcinogens. Consequently, efficient and accurate environmental monitoring of trace levels of these organic pollutants is necessary to protect the population against their hazardous effects. Passive sampling techniques have gained notoriety for environmental monitoring and have been proven highly sensitive to temporal variations. This study developed a miniaturized passive sampling device (MPSD) based on hollow fiber liquid-phase microextraction (HF-LPME). The devices were calibrated in the laboratory using an automated calibration system. The results demonstrated the first-order uptake ranges for Diethyl phthalate (DEP), Diisobutyl phthalate (DiBP), Dibutyl phthalate (DBP), Benzyl butyl phthalate (BBP) and Bis(2-ethylhexyl phthalate) (DEHP) between 30 min and 24 h with sampling rates equivalent to 0.009; 0.021; 0.033; 0.085 and 0.003 mL h−1 respectively (R2 between 0.88 and 0.99). The calibrated devices were deployed in 12 marginal lagoons, stretching approximately 330 km along the main river. The extracts recovered from the devices were analyzed by gas chromatography (GC), resulting in the identification and quantification of DEP (0.697–13.7 ng L−1), DiBP (0.100–4.43 ng L−1), DBP (0.014–1.21 ng L−1), BBP (0.218–5.67 ng L−1), and DEHP (0.002–2.24 ng L−1). Despite being frequently identified, DEHP concentrations were well below the maximum established limits, revealing a good water quality in terms of the target PAEs. In contrast, screening the extracts using GCxGC was possible to detect other hazardous pollutants such as pesticides, drugs, and their metabolites. The described device was effective and reliable, providing accurate PAE measurements following short exposure periods. In this sense, its deployment during emergency operations, such as accidental discharges of industrial effluents into natural waters, could continuously and cost-effectively monitor water quality.