What's in the water? – Target and suspect screening of contaminants of emerging concern in raw water and drinking water from Europe and Asia

Rikard Tröger,Hanwei Ren,Daqiang Yin,Cristina Postigo,Phuoc Dan Nguyen,Christine Baduel,Oksana Golovko,Frederic Been,Hanna Joerss,Maria Rosa Boleda,Stefano Polesello,Marco Roncoroni,Sachi Taniyasu,Frank Menger,Lutz Ahrens,Foon Yin Lai,Karin Wiberg

doi:10.1016/j.watres.2021.117099

Abstract

There is growing worry that drinking water can be affected by contaminants of emerging concern (CECs), potentially threatening human health. In this study, a wide range of CECs (n = 177), including pharmaceuticals, pesticides, perfluoroalkyl substances (PFASs) and other compounds, were analysed in raw water and in drinking water collected from drinking water treatment plants (DWTPs) in Europe and Asia (n = 13). The impact of human activities was reflected in large numbers of compounds detected (n = 115) and high variation in concentrations in the raw water (range 15-7995 ng L−1 for ∑177CECs). The variation was less pronounced in drinking water, with total concentration ranging from 35 to 919 ng L−1. Treatment efficiency was on average 65 ± 28%, with wide variation between different DWTPs. The DWTP with the highest ∑CEC concentrations in raw water had the most efficient treatment procedure (average treatment efficiency 89%), whereas the DWTP with the lowest ∑177CEC concentration in the raw water had the lowest average treatment efficiency (2.3%). Suspect screening was performed for 500 compounds ranked high as chemicals of concern for drinking water, using a prioritisation tool (SusTool). Overall, 208 features of interest were discovered and three were confirmed with reference standards. There was co-variation between removal efficiency in DWTPs for the target compounds and the suspected features detected using suspect screening, implying that removal of known contaminants can be used to predict overall removal of potential CECs for drinking water production. Our results can be of high value for DWTPs around the globe in their planning for future treatment strategies to meet the increasing concern about human exposure to unknown CECs present in their drinking water.

Highlights

Large amounts of synthetic organic chemicals are used worldwide in products, goods and daily life (Richardson and Ternes 2014; Benotti et al 2009a; Geissen et al 2015; Ruff et al 2015; Schwarzenbach et al 2006; Stuart et al 2012; Padhye et al 2014b; Sörengård et al 2019)
Concentrations of CECs in raw water and drinking water were screened using comparative data on samples obtained from 13 fullscale drinking water treatment plants (DWTPs) located in different countries and continents
The analyses clearly showed that many known and unknown mobile CECs pass through artificial barriers (DWTP treatment) around the world and are found in treated drinking water, in generally low concentrations

Summary

Introduction

Large amounts of synthetic organic chemicals are used worldwide in products, goods and daily life (Richardson and Ternes 2014; Benotti et al 2009a; Geissen et al 2015; Ruff et al 2015; Schwarzenbach et al 2006; Stuart et al 2012; Padhye et al 2014b; Sörengård et al 2019). Insufficient removal of contaminants of emerging concern (CECs) during drinking water treatment could pose a risk to human exposure (Falconer et al 2006), e.g. to pesticides (Petrovic, Gonzalez, and Barcelo 2003; Badach, Nazimek, and Kaminska 2007; Mekonen et al 2016; Fava et al 2010), pharmaceuticals and personal care products (PPCPs) (Stackelberg et al 2007; Webb et al 2003) and flame retardants (Garcia-Lopez, Rodriguez, and Cela 2010; Wang, Liu, and Yin 2011). Most CEC removal efficiency studies to date have been conducted with a selected number of CECs and little is known about the removal of a broad range of CECs in current full-scale drinking water treatment plants (DWTPs)

Methods

Results

Conclusion