Study on the Stability of Antibiotics, Pesticides and Drugs in Water by Using a Straightforward Procedure Applying HPLC-Mass Spectrometric Determination for Analytical Purposes

The stability of analytes is a critical point in chemical analysis, especially in the field of trace levels residue analysis. Nowadays, due to advances in analytical technology and in separation sciences, the analyses of water have been improved. Unfortunately, in this context, one of the most critical issues in water analysis include compound stability from sampling station to laboratory procedures. This study was carried out to explore the stability of several compounds in water from sampling to analysis concerning analytes reported in implementing decision 2018/840—Watch List. During method development and validation, the stability of compounds was investigated to detect the best operating conditions concerning sampling, extraction and analysis. In this paper, we report a study on the stability of antibiotics, pesticides and drugs in water determined using a straight-forward procedure applying mass spectrometric detection for analytical purposes. The laboratory tests were performed in Milli-Q water and surface water by analyzing samples through direct injection, solvent mixture (Water/ACN) and solid phase extraction system from time 0 to 168 h. All the analytes of the WL are stable in aqueous solutions with the addition of at least 25% ACN even after 168 h, and the analytes have shown a matrix effect on recovery of some analytes such as Famoxadone from sampling results (recovery in surface water 72%). For all the analytes investigated, recoveries were between 70 and 130% by using SPE procedures before UHPLC-MS/MS analysis, which is in good agreement with method validation procedures

Inter-laboratory Validation of Solid- Phase Microextraction for the Determination of Triazine Herbicides and their Degradation Products at ng/l Level in Water Samples.

The accuracy and precision of solid-phase micorextraction (SPME) were validated in an inter-laboratory study including ten lavoratories for the analysis of triazine herbicides and their metabolites at ppt level in aqueous samples. The SPME conditions were optimised in order to obtain maximum sensitivity. It is concluded that SPME is a reliable technique for the quantitative analysis of water samples containing triazine herbicides in concentrations around the European limit of 100 ppt for individual pesticides in drinking water.JRC.(EI)-Environment Institut

Online Solid-Phase Extraction LC-MS/MS: A Rapid and Valid Method for the Determination of Perfluorinated Compounds at Sub ng·L−1 Level in Natural Water

In this research paper, we report a method able to detect perfluorinated compound at pg·L−1 levels in superficial and underground water samples. An online solid phase extraction HPLC-MS/MS method was developed for the analysis of 12 perfluoroalkyl acids (PFASs). The method is based on injection of 5000 µL of water sample in SPE online WAX column followed by chromatography separation and mass spectrometry determination. SPE online elution was performed by water + 0.05% NH4OH and methanol + 0.05% NH4OH, while separation of target compounds was achieved within 10 min by Gemini chromatographic column operating from 1 to 12 pH range and using a mixture of water-methanol + 0.05% NH4OH. Sub ng·L−1 method detection limits (from 0.2 to 5 ng·L−1), linearity (from 0.2 to 250 ng·L−1), accuracy (from 80 to 120%), and precision (RSD less than 15% at LOQs levels) were achieved. The method is capable of measuring PFAS at trace levels, but above all it can reach the limit of 200 pg·L−1 required by European regulation for PFOS determination in surface and underground waters. The method was validated for quantitative analysis of PFASs in real water samples

Determination of Antibiotics, Pesticides, Herbicides, Fungicides and Hormones in Water Bodies in Italy in Occurrence with European Watch List Mechanism by Using an UHPLC-MS/MS System: Method Validation, Quantification and Evaluations

In recent years, the quality of aquatic ecosystems has received increasing attention from European institutions. The Commission Implementing Decision (EU) 2018/840 drafted a Watch List (WL) of compounds to be monitored in Europe. In this study, we report a method based on solid phase extraction with ultra-high-performance liquid chromatography, coupled with a triple-quadrupole mass spectrometer (UHPLC-MS/MS) to analyze the whole water sample. The method was developed and validated for the determination of 12 listed compounds. The employment of solid-phase extraction by a horizon system ensures the analysis of the entire body of samples and minimizes sample manipulation. Different ng L−1 detection limits (from 2 to 50 ng L−1), linearities (from 2 to 500 ng L−1), accuracy (from 70 to 130%) and levels of precision (RSD less 20% at LOQs levels) were assessed to be satisfactory for quantification and confirmation at the levels of interest. The developed method was applied for quantitative analysis for Watch List compounds (with the exception of hormones) in surface water samples from different Italian sites during monitoring activities by the Regional Environmental Protection Agencies in the years 2019 and 2020

Determination of Antibiotics, Pesticides, Herbicides, Fungicides and Hormones in Water Bodies in Italy in Occurrence with European Watch List Mechanism by Using an UHPLC-MS/MS System: Method Validation, Quantification and Evaluations

In recent years, the quality of aquatic ecosystems has received increasing attention from European institutions. The Commission Implementing Decision (EU) 2018/840 drafted a Watch List (WL) of compounds to be monitored in Europe. In this study, we report a method based on solid phase extraction with ultra-high-performance liquid chromatography, coupled with a triple-quadrupole mass spectrometer (UHPLC-MS/MS) to analyze the whole water sample. The method was developed and validated for the determination of 12 listed compounds. The employment of solid-phase extraction by a horizon system ensures the analysis of the entire body of samples and minimizes sample manipulation. Different ng L−1 detection limits (from 2 to 50 ng L−1), linearities (from 2 to 500 ng L−1), accuracy (from 70 to 130%) and levels of precision (RSD less 20% at LOQs levels) were assessed to be satisfactory for quantification and confirmation at the levels of interest. The developed method was applied for quantitative analysis for Watch List compounds (with the exception of hormones) in surface water samples from different Italian sites during monitoring activities by the Regional Environmental Protection Agencies in the years 2019 and 2020

Estrogenicity of chemical mixtures revealed by a panel of bioassays

International audienceEstrogenic compounds are widely released to surface waters and may cause adverse effects to sensitive aquatic species. Three hormones, estrone, 17β-estradiol and 17α-ethinylestradiol, are of particular concern as they are bioactive at very low concentrations. Current analytical methods are not all sensitive enough for monitoring these substances in water and do not cover mixture effects. Bioassays could complement chemical analysis since they detect the overall effect of complex mixtures. Here, four chemical mixtures and two hormone mixtures were prepared and tested as reference materials together with two environmental water samples by eight laboratories employing nine in vitro and in vivo bioassays covering different steps involved in the estrogenic response. The reference materials included priority substances under the European Water Framework Directive, hormones and other emerging pollutants. Each substance in the mixture was present at its proposed safety limit concentration (EQS) in the European legislation. The in vitro bioassays detected the estrogenic effect of chemical mixtures even when 17β-estradiol was not present but differences in responsiveness were observed. LiBERA was the most responsive, followed by LYES. The additive effect of the hormones was captured by ERα-CALUX, MELN, LYES and LiBERA. Particularly, all in vitro bioassays detected the estrogenic effects in environmental water samples (EEQ values in the range of 0.75–304 × EQS), although the concentrations of hormones were below the limit of quantification in analytical measurements. The present study confirms the applicability of reference materials for estrogenic effects' detection through bioassays and indicates possible methodological drawbacks of some of them that may lead to false negative/positive outcomes. The observed difference in responsiveness among bioassays – based on mixture composition - is probably due to biological differences between them, suggesting that panels of bioassays with different characteristics should be applied according to specific environmental pollution conditions