|Natural attenuation behavior of typical sulfonamides in the surface water
|Ecological toxicity;Natural attenuation;Structural equation modeling;Sulfonamides;Transformation products
Due to its extensive usage and frequent detection in the surface water, the environmental behavior and ecological toxicity of sulfonamides have received increasing concerns. This study investigated the attenuation pattern and factors influencing the natural attenuation of 10 typical sulfonamides by simulating hydrolysis, direct and indirect photolysis, bacterial degradation and microbial degradation in microcosm. The results showed that 55% to 100% of sulfonamides could be removed under natural attenuation with the half-life from 14.7 h to 115.5 h, which indicated the sulfonamides can be naturally attenuated after entering the river surface water. The structural equation modeling approach demonstrated that the direct and indirect photolysis were the major factors contributing to the natural attenuation of sulfonamides, while hydrolysis, bacterial degradation, and microbial degradation were not effective. Seven transformation products were identified by high resolution mass spectrometry, which suggested that the sulfonamides attenuation mainly occurred through N-S cleavage and hydroxylation. The toxicity evaluation based on ECOSAR showed that the toxicity of the transformation products was lower than the parent compounds. However, the transformation products might still have potential environmental risks and further studies should be conducted. ? 2021, Science Press. All rights reserved.
|Appears in Collections:
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.