Journal article

Microbial inhibition by pharmaceutical antibiotics in different soils - Dose-response relations determined with the iron(III) reduction test


Authors listThiele-Bruhn, S

Publication year2005

Pages869-876

JournalEnvironmental Toxicology and Chemistry

Volume number24

Issue number4

ISSN0730-7268

eISSN1552-8618

DOI Linkhttps://doi.org/10.1897/04-166R.1

PublisherOxford University Press


Abstract
Soil contamination from pharmaceuticals is an emerging problem, though quantitative data on their microbial effects are lacking. Thus, nine pharmaceutical antibiotics were tested for their effects on the microbial iron(III) reduction in six different topsoils. Complete dose-response curves were obtained and best-fit by sigmoidal Logit, Weibull, Box-Cox Logit, and Box-Cox Weibull equations (r(2) 0.73-1.00). The derived effective doses (ED [mu mol/kg soil]) for the different antibiotics increased in the order (average ED50 in parentheses) chlortetracycline (53) < sulfadimethoxine (58) < oxytetracycline (170) < sulfacliazine (190) < sulfadimidine (270) = tetracycline (270) < sulfapyridine (430), though no effect was found for sulfanilamide and fenbendazole at doses up to 5,800 and 3,300 mu mol/kg, respectively. Due to a strong soil adsorption, especially of the tetracyclines, the corresponding effective concentrations in the soil solution (EC50), derived from sorption experiments, were considerably smaller and ranged from 0.004 mu mol/L (chlortetracycline) to 120 mu mol/L (sulfapyridine). The effects of the antibiotics were governed by soil sorptive properties, especially the concentration of soil organic matter. The microbial inhibition was influenced indirectly by the soil pH, which affects the ionization status of the amphoteric antibiotics.



Citation Styles

Harvard Citation styleThiele-Bruhn, S. (2005) Microbial inhibition by pharmaceutical antibiotics in different soils - Dose-response relations determined with the iron(III) reduction test, Environmental Toxicology and Chemistry, 24(4), pp. 869-876. https://doi.org/10.1897/04-166R.1

APA Citation styleThiele-Bruhn, S. (2005). Microbial inhibition by pharmaceutical antibiotics in different soils - Dose-response relations determined with the iron(III) reduction test. Environmental Toxicology and Chemistry. 24(4), 869-876. https://doi.org/10.1897/04-166R.1



Keywords


CURVESDOSE-RESPONSE CURVESeffective concentrationseffective dosespharmaceutical antibioticssoil microbial activity

Last updated on 2025-02-04 at 06:49