Effect of Soil Solution Properties and Cu2+ Co-Existence on the Adsorption of Sulfadiazine onto Paddy Soil.

Ziwen Xu,Aiju Liu,Shiquan Lv,Liang Chao,Kai Liu,Mingyue Li,Fangxu Rong,Xin Wang,Shuxiang Hu,Mengyang Dong

doi:10.3390/ijerph182413383

Abstract

Paddy soils are globally distributed and saturated with water long term, which is different from most terrestrial ecosystems. To better understand the environmental risks of antibiotics in paddy soils, this study chose sulfadiazine (SDZ) as a typical antibiotic. We investigated its adsorption behavior and the influence of soil solution properties, such as pH conditions, dissolved organic carbon (DOC), ionic concentrations (IC), and the co-existence of Cu2+. The results indicated that (1) changes in soil solution pH and IC lower the adsorption of SDZ in paddy soils. (2) Increase of DOC facilitated the adsorption of SDZ in paddy soils. (3) Cu2+ co-existence increased the adsorption of SDZ on organic components, but decreased the adsorption capacity of clay soil for SDZ. (4) Further FTIR and SEM analyses indicated that complexation may not be the only form of Cu2+ and SDZ co-adsorption in paddy soils. Based on the above results, it can be concluded that soil solution properties and co-existent cations determine the sorption behavior of SDZ in paddy soils.

Highlights

The concentration of SDZ was increased to 40 μmol L−1 in the soil solutions and they were centrifuged after the adsorption reached equilibrium
The present study indicated further that the SDZ chemicals were the soil organic matter, as the SDZ adsorption increased with soil organic matter addition adsorbed to the soil organic matter, as the SDZ adsorption increased with soil organic (Figure 1f), and there was more obvious signal noise for soil OC constituents than the clay matter addition (Figure 1f), and there was more obvious signal noise for soil OC constitafter being treated with SDZ (Figure 3)
The change of soil solution pH and ion concentration lowered the SDZ adsorption on paddy soil, but it was increased with the addition of organic matter

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Overuse and the uncontrolled disposal of antibiotics have caused severe environmental problems, especially for the soil environment [1,2,3]. As one of the main crops in the world, rice is widely planted and feeds the majority of the world’s population; while over

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Methods

Conclusion