Toxicity of pharmaceuticals in binary mixtures: Assessment by additive and non-additive toxicity models.
Current risk assessment in many countries, including European Union, is still placing focus on single substances rather than their mixtures, although mixtures are commonly found in the environment. To overcome this problem and gain new insights, six pharmaceuticals, namely: azithromycin (AZM), erythromycin (ERM), carbamazepine (CBA), oxytetracycline (OTC), dexamethasone (DXM), and diclofenac (DCF), were selected in order to analyze their combined toxicity in binary mixtures. Overall, 45 binary mixtures were analyzed. Single component toxicities were determined as well, for modelling purpose. Two most common mathematical models for the description of mixture toxicities were applied: concentration addition (CA) and independent action (IA) model. Comparison of the predicted and experimentally obtained toxicities provided information about the modes of toxicity action in the mixtures. OTC-DCF binary mixture indicated synergism with respect to additive behavior (CA model). All other binary combinations containing OTC or DCF were acting very similarly: the synergism with respect to additive behavior was observed for OTC-CBA and DCF-CBA combinations, while OTC-AZM, OTC-ERM, DCF-AZM and DCF-ERM exhibited antagonistic behavior with respect to CA model. All the remaining binary mixtures indicated additive behavior. The applicability of IA model as a proof of independent toxic action of the components was confirmed in cases of DCF-AZM, DCF-ERM, and OTC-AZM mixtures.
['Ukić|Š|Š|', 'Sigurnjak|M|M|', 'Cvetnić|M|M|', 'Markić|M|M|', 'Stankov|M Novak|MN|', 'Rogošić|M|M|', 'Rasulev|B|B|', 'Lončarić Božić|A|A|', 'Kušić|H|H|', 'Bolanča|T|T|']
D048908:Aliivibrio fischeri D004305:Dose-Response Relationship, Drug D004357:Drug Synergism D008962:Models, Theoretical D015394:Molecular Structure D004364:Pharmaceutical Preparations D018675:Toxicity Tests D014874:Water Pollutants, Chemical
Toxicity Pharmaceuticals Binary mixtures Concentration addition Independent action