Toxicity of wastewater from health care facilities assessed by different bioassays.

Objectives: The purpose of this study was to determine toxicity of wastewater from hospitals in the Czech Republic using traditional and alternative toxicological methods. The pilot study comprised weekly dynamics of sewage ecotoxicity of treated wastewater from one hospital in two different seasons. A detailed investigation of wastewater ecotoxicity, genotoxicity and reprotoxicity followed in five different hospitals.

Bioindicators of wastewater ecotoxicity.

Wastewater, especially containing hospital effluents, exhibits high chemical complexity and specificity since it includes various chemicals, biocides, pharmaceuticals, surfactants, radionuclides, disinfectants and pathogens. Biological tests provide true evidence of the wastewater quality and unlike chemical analytical tests show comprehensive pollution effects on the environment and human health. Normalized conventional bioassays are not sensitive enough for ecotoxicological evaluation of wastewater and there is a great need for the development of suitable sensitive bioassays in order to characterize properly the residual toxicity of treated effluents.