Validation of sampling techniques and SPE-UPLC/MS/MS for home and personal care chemicals in the Songhua Catchment, Northeast China

Abstract

A method for the simultaneous determination of 18 home and personal care chemicals (HPCCs) in river water and wastewater was developed using solid-phase extraction and ultra-high-performance liquid chromatography with tandem mass spectrometry (SPE and UPLC/MS/MS). A series of tests were designed to find the potential background interference and loss of HPCCs during the sample preservation and pretreatment process. Our results suggested that a considerable amount of some target compounds were lost with increasing days of storage even at 4 °C. Accordingly, the samples were stored acidified and refrigerated, including during transportation, to reduce the losses. Experiments on filtration of water samples suggested that recoveries of many HPCCs were significantly affected by the filtration. It is therefore recommended to avoid filtration of water samples where possible. The internal standard corrected recoveries for the HPCCs ranged from 64.2 to 107.0%, except for benzisothiazolone which did not have an appropriate internal standard, in river water which was considered to be the most difficult matrix. The method detection limits for river water, influent and effluent samples were in the ranges of 0.17 to 42 ng/L, 13 to 5100 ng/L, and 0.50 to 200 ng/L, respectively. The validated method was applied for the determination of HPCCs in sewage water collected from a full-scale wastewater treatment plant (WWTP) in a typical urban city in Northeast China and from river water upstream and downstream of the WWTP. Linear alkylbenzene sulphonate, caffeine, methyl paraben, benzalkonium chloride, triclocarban, and triclosan were the major compounds detected in the river water and wastewater samples. Sampling variability for the WWTP (intra-day and inter-day) and cross-river was also determined with the purpose of designing future monitoring requirements. Small variations in these samples confirmed that composite samples and a single sampling event would be representative for future use.