ABSTRACT
Slaughterhouse industry produces large volumes of polluted wastewater, which cause negative impacts on the environment. The objective of this study was to assess the effect of electron-beam irradiation on the ecotoxicity of slaughterhouse effluents with absorbed doses up to 35 kGy. Two acute toxicity assays were applied to evaluate the efficiency of irradiation onto toxicity of wastewater. The exposed living-organisms were a luminescent bacteria Vibrio fischeri, and a freshwater microcrustacean Daphnia similis. Also, the total organic carbon was analysed in order to determine any possible organic carbon removal after irradiation. The ecotoxicological results evidenced that both living-organisms were suitable for the measurements. Therefore, the results demonstrated the toxicity of the effluent and its similarity for both organisms as well as the potential of radiation to reduce these effects. The 35 kGy dose was very effective for reducing toxic effects of slaughterhouse wastewater for daphnids suggesting that ionizing radiation could be used as a tool for removing toxic charge of such effluents. The type of contamination presented by the effluent justify the needs for alternatives of treatment.
Acknowledgements
The authors are grateful to International Atomic Energy Agency (Contract No. 16513) and to the slaughterhouse (Centro de Abate de Suínos do Oeste) for their kind permission to collect all the samples necessary for the accomplishment of this work. R. Melo acknowledges a grant from FCT (SFRH/BD/41996/2007) and an IAEA fellowship (POR/05003 – ‘Radiation Processing Facilities and Applications’).
Disclosure statement
No potential conflict of interest was reported by the author(s).