Determination of 18 Biocides in Both the Dissolved and Particulate Fractions of Urban and Surface Waters by HPLC-MS/MS

Abstract

A robust method is provided to analyze 18 hydrophilic and hydrophobic biocides in both dissolved and particulate fractions of five types of urban and surface waters using high performance liquid chromatography coupled to tandem mass spectrometry. The linearity, accuracy and intermediate precision were validated. The target biocides were enriched by solid phase extraction using Chromabond HR-X 200 mg cartridges and eluted with methanol, ethyl acetate and dichloromethane. Suspended matter was extracted by microwave-assisted extraction in methanol and dichloromethane. Recoveries and variability (respectively >75% and < 30% for most of the target biocides and matrices) made it possible to quantify biocides at trace level in all matrices. LOQs were in the range of ng/L in the dissolved fraction and in the range of ng/g.dw in the particulate fraction for most of the biocides and matrices and were generally lower than those reported in previous studies. The method was successfully applied to surface water, treated and untreated wastewater, combined sewer overflows, and stormwater providing, unique data in these matrices for some substances, in particular with respect to particle contamination. In urban waters, concentrations of most of the biocides ranged from 10 to 200 ng/L. Diuron, isothazolinone and benzalkonium concentrations could reach 0.9, 0.9 and 20 µg/L respectively. In rivers, most of the biocides were measured at less than 10 ng/L, but higher concentrations were observed for benzalkoniums (up to 200 ng/L) or after rain events, which indicates biocide transfer from urban surfaces into the aquatic environment during wet weather.

Anionic surfactants monitoring in healthcare facilities — a case of Belo Horizonte City, Brazil

“…Moreover, analytical standards are required in addition to the metabolites formed, which are not always available for purchase. It also involves the pre-treatment of liquid and solid samples, from the collection and preservation until the solid phase extraction, its recovery, and the validation of the methodology (Paijens et al, 2020 ).…”

Urban pathways of biocides towards surface waters during dry and wet weathers: Assessment at the Paris conurbation scale

“…Uncertainty on dissolved concentrations was estimated via the coefficient of variation (? @ ) of the replicates obtained during the validation of the method [33]. Concerning the particulate fraction, uncertainty related to TSS concentration was previously determined as 10% [40,41] and that related to the particulate extraction is unknown but supposed to be lower than uncertainty on the dissolved fraction, as previously reported by Wieck et al (2018) [42] for most of the analysed biocides.…”

“…All standards of high purity (> 90%) were commercially available and purchased from A2S (France), Dr. Ehrenstorfer (Germany), Sigma Aldrich (France) and CDN Isotopes (Canada). The procedure applied for the analysis of these compounds was previously described by [33]. Briefly, samples were filtered within 24 h after sampling through 0.7 µm glass fibre filters (GF/F, Whatman, UK) previously heated at 500 °C for 2 h. Both the dissolved and particulate fractions of water samples were analysed.…”

Biocidal substances in the Seine River: contribution from urban sources in the Paris megacity

“…The separation was then performed on an Acquity UPLC® HSS T3 column (100 mm × 2.1 mm, 1.7 μm) from Waters. The determination of detection and quantification limits (LOD and LOQ) has been explained in the above mentioned article 38 and is based on the quantification range. The instrumental limit of detection (LODi) was determined as the lowest concentration at which both quantification and confirmation transitions were achieved.…”

“…Information on these biocides is provided in the ESI † (Table S2). The procedure used for biocide analysis has been the core subject of a previous publication 38 and therefore will only be briefly described in the present section. The 18 targeted biocides were analysed in both the dissolved and particulate fractions of the water samples.…”