Assessing the potential for nevirapine removal and its ecotoxicological effects on Coelastrella tenuitheca and Tetradesmus obliquus in aqueous environment

Karen Reddy; Nirmal Renuka; Sheena Kumari; Sachitra Kumar Ratha; Brenda Moodley; Kriveshin Pillay; Faizal Bux

doi:10.1016/j.envpol.2022.120736

Assessing the potential for nevirapine removal and its ecotoxicological effects on Coelastrella tenuitheca and Tetradesmus obliquus in aqueous environment

Environ Pollut. 2023 Jan 15:317:120736. doi: 10.1016/j.envpol.2022.120736. Epub 2022 Nov 29.

Authors

Karen Reddy¹, Nirmal Renuka², Sheena Kumari¹, Sachitra Kumar Ratha³, Brenda Moodley⁴, Kriveshin Pillay¹, Faizal Bux⁵

Affiliations

¹ Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban, 4000, South Africa.
² Algal Biotechnology Laboratory, Department of Botany, Central University of Punjab, Bathinda, 151401, India.
³ Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban, 4000, South Africa; Phycology Laboratory, CSIR-National Botanical Research Institute, Lucknow, 226001, India.
⁴ School of Chemistry and Physics, College of Agriculture, Engineering and Sciences, University of KwaZulu-Natal, Private Bag X54001, Westville, Durban, 4000, South Africa.
⁵ Institute for Water and Wastewater Technology, Durban University of Technology, PO Box 1334, Durban, 4000, South Africa. Electronic address: faizalb@dut.ac.za.

PMID: 36460185
DOI: 10.1016/j.envpol.2022.120736

Abstract

Remediation of the antiretroviral (ARV) drug, nevirapine (NVP) has attracted considerable scientific attention in recent years due to its frequent detection and persistence in aquatic environments and potential hazards to living organisms. Algae-based technologies have been emerging as an environmentally friendly option for the removal of pharmaceutical compounds, but their ARV drug removal potential has not been fully explored yet. This study aimed to explore the ecotoxicity and removal potential of NVP by two microalgal species, Coelastrella tenuitheca and Tetradesmus obliquus. Lower environmental concentrations (up to 200 ng L^-1) of NVP enhanced the microalgal growth, and the highest dry cell weight of 941.27 mg L^-1 was obtained in T. obliquus at 50 ng L^-1 NVP concentration. Both microalgae showed varying removal efficiencies (19.53-74.56%) when exposed to NVP concentration levels of up to 4000 ng L^-1. At the late log phase (day 8), T. obliquus removed the highest percentage of NVP (74.56%), while C. tenuitheca removed 48% at an initial NVP concentration of 50 ng L^-1. Photosynthetic efficiency (Fv/Fm and rETR) of the two microalgal species, however, was not affected by environmental concentrations of NVP (up to 4000 ng L^-1) at the mid log phase of growth. SEM analysis demonstrated that both algal species produced distinct ridges on their cell surfaces after NVP uptake. In the ecotoxicity study, the calculated IC₅₀ values of NVP (0-100 mg L^-1) after 96 h of exposure were 23.45 mg L^-1 (C. tenuitheca) and 18.20 mg L^-1 (T. obliquus). The findings of the present study may contribute to a better understanding of the environmental hazards associated with NVP and the efficacy of microalgae in removing this pharmaceutical from aquatic environments.

Keywords: Antiretroviral drug; Bioremediation; Ecotoxicity; Emerging micropollutants; Microalgae; Wastewater.

MeSH terms

Chlorophyceae* / metabolism
Microalgae* / metabolism
Nevirapine / metabolism
Pharmaceutical Preparations / metabolism
Water / metabolism

Substances

Nevirapine
Water
Pharmaceutical Preparations