Katrin Zessel, S. Mohring, G. Hamscher
Apr 1, 2014
Citations
2
Influential Citations
41
Citations
Quality indicators
Journal
Chemosphere
Abstract
BACKGROUND This study assessed the photochemical fate of nine sulfonamides (sulfamerazine, sulfanilamide, sulfamethoxypyridazine, sulfamethoxazole, sulfachloropyridazine, sulfamethazine, sulfadiazine, sulfathiazole and sulfadimethoxine) during a 6h irradiation period with UVA/UVB-light and UVA-light and over 7 days under natural (sunlight) conditions. The cell growth inhibition effect and cytotoxicity of sulfonamides and their photodegradation products was investigated over 24 and 48 h with murine fibroblasts and keratinocytes. Antibacterial activity of the degradation products was studied using the Geobacillus stearothermophilus var. Calidolactis C953 assay. RESULTS UVA/UVB treatment of several sulfonamide solutions results in degradation of the compounds in different amounts with the highest degradation rate for sulfathiazole and sulfanilamide. The UVA/UVB light degradation products exhibit no antimicrobial activity. Sun light exposure over 7 days reveals a similar degradation pattern of the different sulfonamides, albeit to a different extent. Compared with UVA/UVB-irradiation, UVA-irradiated sulfonamides degrade to a lesser extent (except sulfamethazine). There was no impact on cell toxicity of the UVA/UVB-degrading products except for sulfanilamide, while a slight impact on cell proliferation was observed. CONCLUSIONS All studied sulfonamides undergo photodegradation under UV-light exposure to a greater or lesser extent. The degradation products have no cytotoxic potential except sulfanilamide and have a slight impact on cell proliferation. All degradation products showed no antibacterial activity. Thus, UV-light exposure seems to represent an adequate method for inactivating sulfonamides with regard to their antimicrobial activity.