Tetracycline-Induced Release and Oxidation of As(III) Coupled with Concomitant Ferrihydrite Transformation

Abstract

Cocontamination with tetracycline (TC) and arsenic (As) is very common in paddy fields. However, the process and underlying mechanism of arsenite (As­(III)) transformation on iron mineral surfaces in the presence of antibiotic contaminants remain unclear. In this study, the release and oxidation of As­(III) on ferrihydrite (Fh) surfaces and Fh transformation in the presence of TC under both aerobic and anaerobic conditions were investigated. Our results indicated that the TC-induced reductive dissolution of Fh (Fe­(II) release) and TC competitive adsorption significantly promote the release of As, especially under anaerobic conditions. The release of As was increased with increasing TC concentration, whereas it decreased with increasing pH. Interestingly, under both aerobic and anaerobic conditions, the addition of TC enhanced the oxidation of As­(III) by Fh and induced the partial transformation of Fh to lepidocrocite. Under aerobic conditions, the adsorbed Fe­(II) activated the production of reactive oxygen species (·OH and 1O2) from dissolved O2, with Fe­(IV) being responsible for As­(III) oxidation. Under anaerobic conditions, the abundant oxygen vacancies of Fh affected the oxidation of As­(III) during Fh recrystallization. Thus, this study provided new insights into the role of TC on the migration and transformation of As coupled with Fe in soils.

The Oxidation and Immobilization of As(III) by Colloidal Ferric Hydroxide in the Concomitant Pollution of Oxytetracycline

“…The reaction between Fe­(II) and H 2 O 2 (eq ) produced Fe­(IV) in near neutral or alkaline conditions, which can also induce As­(III) oxidation. , PMSO was selected as the quencher of Fe­(IV). Since both •OH and Fe­(IV) can oxidize PMSO ( k PMSO, • OH = 3.61 × 10 9 M –1 ·s –1 , k PMSO, Fe(IV) = 1.23 × 10 5 M –1 ·s –1 ), overdosed MeOH was added together with PMSO to exclude the effect of • OH .…”

“…It has been reported that some antibiotic molecules can complex with surface Fe­(III) of iron minerals and that electron transfer within the complex induces the reduction of Fe­(III) and the degradation of antibiotics. , It was presumed that TCs can play the same role as these organic molecules, promoting the generation of ROS and contributing to the oxidation of co-existing As­(III). A recent study reported that TTC induced the reductive dissolution of ferrihydrite (Fe­(II) release) and led to the release and oxidation of As­(III) adsorbed by ferrihydrite in both aerobic and anaerobic conditions . Competitive adsorption of TTC significantly promotes the release of As.…”

“…A recent study reported that TTC induced the reductive dissolution of ferrihydrite (Fe(II) release) and led to the release and oxidation of As(III) adsorbed by ferrihydrite in both aerobic and anaerobic conditions. 30 Competitive adsorption of TTC significantly promotes the release of As.…”

Highly Dispersed Magnetite Nanoparticles on Biochar with Sulfonation Modification for Simultaneous Removal of Arsenite and Tetracycline from Aqueous Solutions: Performance and Mechanistic Insight

“…The increasing toxicity and complexity due to the combined pollution of heavy metals and antibiotics in aqueous media, arising from worldwide urbanization and industrialization, is causing public concern over environmental issues. − As a result of natural and anthropogenic activities including waste discharge, rock weathering, and mining, high levels of arsenic (up to 1350 μg/L) have been frequently detected in groundwater in the northwest of China, for example, Inner Mongolia, Xinjiang Uighur, and Guizhou province, which markedly exceed the detection limit (10 μg/L) set by the World Health Organization (WHO) . Meanwhile, in the rural areas contaminated by arsenic, pharmaceutical antibiotics (e.g., tetracycline) used for animals and humans to treat infectious diseases are often directly released into domestic sewage, which will be reutilized for irrigation of farmland and inevitably lead to the antibiotic pollution of groundwater. , Excessive and long-term exposure to heavy metals and antibiotics can adversely affect the growth of animals and plants and even cause a series of health-related problems such as cancer, neurotoxicity, and chronic kidney disease through migration and the food chain. − Recent studies have demonstrated that the presence of tetracycline could reduce the immobility of arsenic in aqueous solutions, and meanwhile, the presence of high concentrations of arsenic also inhibited the removal of tetracycline. ,, Undoubtedly, their interactive behavior adversely affects the overall treatment efficiency. Therefore, the simultaneous removal of arsenic and tetracycline is of great necessity but remains a significant challenge in the water treatment process.…”

“…4 Meanwhile, in the rural areas contaminated by arsenic, pharmaceutical antibiotics (e.g., tetracycline) used for animals and humans to treat infectious diseases are often directly released into domestic sewage, which will be reutilized for irrigation of farmland and inevitably lead to the antibiotic pollution of groundwater. 5,6 Excessive and long-term exposure to heavy metals and antibiotics can adversely affect the growth of animals and plants and even cause a series of health-related problems such as cancer, neurotoxicity, and chronic kidney disease through migration and the food chain. 7−10 Recent studies have demonstrated that the presence of tetracycline could reduce the immobility of arsenic in aqueous solutions, and meanwhile, the presence of high concentrations of arsenic also inhibited the removal of tetracycline.…”