Monitoring and Ecotoxicity Assessment of Emerging Contaminants in Wastewater Discharge in the City of Prague (Czech Republic)

Veronica R Diaz-Sosa,Diana L Cardenas-Chavez,Mireya Tapia-Salazar,Jiri Wanner

doi:10.3390/w12041079

Abstract

Emerging contaminants (ECs) are not monitored nor regulated consistently, but may have negative effects on human health and ecosystem balance. Although pharmaceuticals and personal care products are among the main ECs found in surface and wastewater, their toxicity and fate are currently not sufficiently studied. In this study, we analyzed for the first time a group of 46 ECs in the secondary effluent of the wastewater treatment plants (WWTP) of Prague. Thirty-seven compounds were identified in the discharge to surface water. Three compounds had no toxicology information on Artemia salina: furosemide, hydrochlorothiazide, and tramadol. We performed acute toxicity (LC50) tests and enzyme assays after 24 and 48 h at room temperature and 28 °C for these three compounds. LC50 ranged from 225.01 mg/L for furosemide, the most toxic, up to above 14,000 mg/L for tramadol. Changes in enzymatic activity for GST, GPx, AChE, and LDH when A. salina were exposed to LC25 for each contaminant were conspicuous and significant in a contaminant-, exposure time-, and temperature-dependent manner. These biochemical markers complement the toxicity profile of these contaminants in aquatic ecosystems and highlight the need for further research on other ECs and their implications, and the regulations required to protect human and ecological health.

Highlights

In past decades, wastewater moved from being perceived as a threat to public health to being considered as a raw material for energy production and recovery of precious resources, including water itself [1]
Secondary effluent samples were taken from the secondary clarifier of the wastewater treatment plants (WWTP) in Prague
Out of the 46 compounds tested in the secondary effluent samples from Prague WWTP, only 37 were present (Table 1) and nine were not found or not possible to quantify under the analytical conditions used in this study

Summary

Introduction

Wastewater moved from being perceived as a threat to public health to being considered as a raw material for energy production and recovery of precious resources, including water itself [1]. Water resources started to become scarce in many regions around the world, mainly where the climatic conditions are unfavorable and population and water consumption are increasing. This perspective implies a strict control in the quality of the reused water, such that it does not represent a risk to the environment and health of its users and possible consumers. Recent scientific evidence has redirected attention to a new and growing threat known as emerging contaminants (ECs) These micropollutants are natural or synthetic substances that are not monitored nor regulated in a consistent manner, they may have adverse effects on human health and ecosystem balance [2,3].

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Results