Occurrence and risk assessment of azole antifungal drugs in water and wastewater

Hailemariam Abrha Assress; Hlengilizwe Nyoni; Bhekie B Mamba; Titus A M Msagati

doi:10.1016/j.ecoenv.2019.109868

Occurrence and risk assessment of azole antifungal drugs in water and wastewater

Ecotoxicol Environ Saf. 2020 Jan 15:187:109868. doi: 10.1016/j.ecoenv.2019.109868. Epub 2019 Nov 2.

Authors

Hailemariam Abrha Assress¹, Hlengilizwe Nyoni¹, Bhekie B Mamba², Titus A M Msagati³

Affiliations

¹ University of South Africa, College of Science Engineering and Technology, Nanotechnology and Water Sustainability Research Unit, UNISA Science Campus, P.O. Box 392 UNISA 0003, Florida, 1709, Johannesburg, South Africa.
² University of South Africa, College of Science Engineering and Technology, Nanotechnology and Water Sustainability Research Unit, UNISA Science Campus, P.O. Box 392 UNISA 0003, Florida, 1709, Johannesburg, South Africa; State Key Laboratory of Separation Membranes and Membrane Process/National Center for International Joint Research on Membrane Science and Technology, Tianjin, 300387, PR China.
³ University of South Africa, College of Science Engineering and Technology, Nanotechnology and Water Sustainability Research Unit, UNISA Science Campus, P.O. Box 392 UNISA 0003, Florida, 1709, Johannesburg, South Africa; School of Life Sciences and Bio-Engineering, The Nelson Mandela African Institution of Science and Technology, P O Box 447, Tengeru, Arusha, United Republic of Tanzania. Electronic address: msagatam@unisa.ac.za.

PMID: 31689623
DOI: 10.1016/j.ecoenv.2019.109868

Abstract

The occurrence of azole antifungals in the environment presents one of the emerging concerns due to their ecotoxicological threat as well as their potential contribution to the evolution of drug resistant fungi in the environment. In this study, the occurrence of eight commonly prescribed azole antifungal drugs was seasonally determined in influent and effluent water samples from three wastewater treatment plants and a drinking water treatment plant in South Africa. In addition, the risk quotient (RQ) method was employed to investigate the potential ecological and human health risks associated with their presence in the wastewater and/or drinking water. Clotrimazole, econazole, fluconazole, itraconazole, ketoconazole and miconazole were detected at least once in the water samples, while posaconazole and voriconazole were not detected in any of the samples for all seasons at which the samples were collected. Fluconazole was detected at higher frequency (about 96%) with a concentration up to 9959.0 ng L^-1. Clotrimazole had the second highest frequency of detection (about 33%) with a concentration up to 143.3 ng L^-1. Statistically significant temporal variation in clotrimazole (p < 0.05) and spatial variation in fluconazole (p < 0.05) were observed. In general, the preliminary ecological risk assessment based on risk quotient (RQ) calculation indicated that there is currently no high risk against aquatic organisms (Algae, Daphnia and Fish) related to the azole antifungals. Meanwhile, human health risk assessment demonstrated that fluconazole represented high risk in drinking water. Furthermore, risk estimates showed a potential for the detected concentrations of fluconazole and itraconazole in water samples to pose moderate to high risk for development of antifungal drug resistance. Some of the azole antifungal drugs are ubiquitous in the wastewater and future monitoring and validation studies should be conducted for those drugs that seem to pose human health and ecological risks.

Keywords: Azole antifungals; Occurrence; Risk assessment; Wastewater treatment plant.

MeSH terms

Antifungal Agents / analysis*
Antifungal Agents / toxicity
Aquatic Organisms / drug effects
Azoles / analysis*
Azoles / toxicity
Drinking Water / chemistry*
Drug Resistance, Fungal
Ecotoxicology
Environmental Monitoring / methods*
Humans
Risk Assessment
South Africa
Wastewater / chemistry*
Water Pollutants, Chemical / analysis*
Water Pollutants, Chemical / toxicity

Substances

Antifungal Agents
Azoles
Drinking Water
Waste Water
Water Pollutants, Chemical