Influence of tetracycline on arsenic mobilization and biotransformation in flooded soils

This study examined the effect of tetracycline addition on arsenic (As) mobilization and biotransformation in two contrasting soils (upland soil and paddy soil) under flooded conditions. The soils with added tetracycline (0-50 mg kg(-1)) were incubated for 30 days, and soil properties and microbial functional genes over time were quantified. Tetracycline significantly promoted As reduction and As release into porewater in both soils. The enhancement had resulted from an increase in the concentration of dissolved organic carbon and a decrease in soil redox potential. Tetracycline also increased the abundances of As-reducing genes (arsC and arrA) and the relative abundances of As-reducing bacteria Streptomyces, Bacillus, Burkholderia, Clostridium and Rhodococcus, all of which have been found resistant to tetracycline. These genera play a key part in stimulating As reduction in the presence of tetracycline. The study indicated the significance of tetracycline in the biochemical behavior of As in flooded soils and provided new insights into the potential effects of tetracycline on the quality and safety of agricultural products in the future.

Automated summary

This study found that tetracycline addition significantly promoted the reduction and release of arsenic in flooded soils, mainly by increasing the concentration of dissolved organic carbon and lowering soil redox potential. Additionally, tetracycline also increased the relative abundances of As-reducing genes and resistant bacteria, playing a key role in stimulating As reduction.