Title: Sorption of ivermectin in Nigerian Oxisols and Alfisols: quantitative insights on environmental fate in tropical soils

Authors: Caleb Oluwaseun Ojo; Bamidele Iromidayo Olu-owolabi

Addresses: Faculty of Science and Technology, Energy and Resource Institute, Charles Darwin University, NT, 0810, Australia ' Faculty of Science, Chemistry Department (Environmental Chemistry Unit), University of Ibadan, Ibadan, 200005, Nigeria

Abstract: Because of the toxicity of ivermectin, the study of its environmental fate is necessary. Sorption experiments were done in laboratory batch experiments using two tropical soils. There was initial high sorption in the first 120 min, followed by steady continuous desorption. The pH of the solution had a reciprocal effect on the sorption of ivermectin in both soils. Sorption increased with an increase in ivermectin concentration for the Oxisol and Alfisol. The pseudo-second-order (PSO) kinetic model best describes ivermectin sorption. The adsorption on both soils was explained better by the Freundlich isotherm. An initial increase in the ambient temperature from 25°C to 40°C led to more significant adsorption. The study showed that ivermectin would have high bioavailability once in the environment.

Keywords: pharmaceuticals; Langmuir isotherm; Freundlich isotherm; solution pH; Oxisol; Alfisol.

DOI: 10.1504/IJEP.2023.135415

International Journal of Environment and Pollution, 2023 Vol.72 No.1, pp.56 - 69

Received: 25 Feb 2022
Received in revised form: 28 May 2023
Accepted: 16 Jun 2023
Published online: 11 Dec 2023 *