Microwave Sensors for In Situ Monitoring of Trace Metals in Polluted Water.

Ilaria Frau,Patrizia Onnis,Stephen Wylie,Jeff Cullen,Olga Korostynska,Alex Mason,Patrick Byrne

doi:10.3390/s21093147

Abstract

Thousands of pollutants are threatening our water supply, putting at risk human and environmental health. Between them, trace metals are of significant concern, due to their high toxicity at low concentrations. Abandoned mining areas are globally one of the major sources of toxic metals. Nowadays, no method can guarantee an immediate response for quantifying these pollutants. In this work, a novel technique based on microwave spectroscopy and planar sensors for in situ real-time monitoring of water quality is described. The sensors were developed to directly probe water samples, and in situ trial measurements were performed in freshwater in four polluted mining areas in the UK. Planar microwave sensors were able to detect the water pollution level with an immediate response specifically depicted at three resonant peaks in the GHz range. To the authors’ best knowledge, this is the first time that planar microwave sensors were tested in situ, demonstrating the ability to use this method for classifying more and less polluted water using a multiple-peak approach.

Highlights

IntroductionLegislation to protect the environment first appeared in the early 1970s, when the European Community and the United States made water quality a priority with the First Environmental Action Programme [3,4] and the Federal Water Pollution Control Act, respectively
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Summary

Introduction

Legislation to protect the environment first appeared in the early 1970s, when the European Community and the United States made water quality a priority with the First Environmental Action Programme [3,4] and the Federal Water Pollution Control Act, respectively. The most important pieces of related water legislation are the European Union Water Framework Directive (EU WFD, 2000/60/EU) and the United States Environmental Protection Agency Clean Water Act (US EPA CWA). They aim to assure good water quality by controlling and limiting contaminants to established standards that are regularly revised [5]

Objectives

Methods

Results

Conclusion