The potential of fungi to improve surface water quality in Amsterdam: a review

Abstract

This review presents the most important pollutants in the surface waters of Amsterdam and an overview of studies that assessed the removal of these pollutants from water by fungi. Amsterdam functions as a case study for the Netherlands in general, a country that is among the lowest in the European ranking on water quality. Chemical pollutants are ubiquitous and present in excessive amounts in Dutch surface water, exceeding the norms set by the 2027 European Water Framework Directive (EWFD) in the majority of the water bodies. To reach the norms, measures have to be taken in the coming years. Mycoremediation seems to be a promising, cost-effective measure, which can be implemented in water treatment plants to prevent pollutants to flush to the surface water. From the EWFD pollutants, three types of metals, seven types of PAHs, the biocide tributyltin cation, and fertilizers ammonium and phosphate were found to be the most problematic pollutants in Amsterdam canals. Nearly all metals and PAHs were shown to be effectively removed by different types of fungi, especially white-rot fungi such as Pleurotus ostreatus. The majority of the metals was removed with a removal rate of >95%. Other pollutants that are not included in the EWFD but are regarded as abundant in Amsterdam canals are drug residues and Eschecheria coli. Nearly all of these were shown to be effectively removed by fungi. T. versicolor showed to be the most effective species to remove drug residues (up to 100% removal rate) and P. ostreatus to remove E. coli (up to 99.7%) from wastewater. The majority of these pollutants were studied in mycoremediation research in both lab conditions as well as using real wastewater. The step towards implementation of mycoremediation is therefore relatively small, and could be realised within years. It is highly recommended to start testing these techniques in wastewater treatment plants in Amsterdam, so that pollutant levels in their effluents can be minimized.