Unveiling the Occurrence and Potential Ecological Risks of Organophosphate Esters in Municipal Wastewater Treatment Plants across China

Abstract

Organophosphate esters (OPEs) discharged from wastewater treatment plants (WWTPs) have attracted increasing concerns because of their potential risks to aquatic ecosystems. The identification of the structures of OPEs is a prerequisite for subsequent assessment of their environmental impacts, which could hardly be accomplished using traditional target analytical methods. In this study, we describe the use of suspect and nontarget screening techniques for identification of organophosphate triesters and diesters (tri-OPEs and di-OPEs) in the influent and effluent samples acquired from 25 municipal WWTPs across China. There are totally 33 different OPE molecules identified, 11 of which are detected in wastewater for the first time and 4 are new to the public. In all tested samples, di-OPEs account for a significant portion (53% on average) of the total OPEs (ng/L−μg/L). More importantly, most of the OPEs could not be eliminated after treatment in these WWTPs, while some of the di-OPEs even accumulate. The research priority of OPEs in the effluent based on ecological risk was also analyzed, and the results reflected a previously unrecognized exposure risk of emerging OPEs for aquatic living organisms. These findings present a holistic understanding of the environmental relevance of OPEs in WWTPs on a country scale, which will hopefully provide guidance for the upgrade of treatment protocols in WWTPs and even for the modification of governmental regulations in the future.

Discovering Novel Organophosphorus Compounds in Wastewater Treatment Plant Effluents through Suspect Screening and Nontarget Analysis

“…Both compounds have been detected in wastewater samples. 31,35 DEGBBCPP occurred in all WWTP effluents, similar to a previous study. 31 The identifications of six aryl tri-OPEs were typically supported by the presence of characteristic fragments of monophenyl phosphate (m/z 175.01547), diphenyl phosphate (m/z 251.04677 and m/z 233.03621), or triphenyl phosphate (m/z 327.07807) (Figure S2).…”

“…Nontarget screening was performed using 14 characteristic fragments compiled from the literature 30,31,34 and identified suspect compounds (Table S4 using Xcalibur Qual Browser (Thermo Scientific) to extract MS/MS chromatograms for these characteristic fragments in each isolation window with a mass tolerance of 5 ppm. Potential precursors were identified by searching the ions in the MS spectra or MS/MS spectra within the corresponding m/z range of the isolation window.…”

Nontarget Identification of Novel Organophosphorus Flame Retardants and Plasticizers in Rainfall Runoffs and Agricultural Soils around a Plastic Recycling Industrial Park

“…Most OPEs are additives rather than chemically bonded to consumer products such as textiles, building materials, and personal care products. Consequently, they are readily released via abrasion, volatilization, diffusion, or leaching, ,, posing ecological and health risks due to their endocrine-disrupting toxicities. – Furthermore, the release of OPEs can be expected to intensify during recycling and reprocessing, but the source characteristics of this release remain unknown.…”

First Evidence of the Bioaccumulation and Trophic Transfer of Tire Additives and Their Transformation Products in an Estuarine Food Web

“…Identifying priority contaminants has been a pressing issue in recent years, but standardized identification methods have not yet been established. Previous studies have identified the priority contaminants in WWTPs, and surface waters based solely on ecological risk scores, , which may be inappropriate for complex environments. Therefore, besides the occurrence and ecological risks of target pollutants, their persistence and bioaccumulation capacity in the estuarine environment also need to be incorporated.…”