Identifying influential priority of factors governing the acute biological toxicity of two kinds of industrial wastewaters

Identifying the key parameters or components mainly contributing to the acute toxicity of wastewater would be helpful to quickly and conveniently reflect their biological toxicity. In this study, the components/parameters and biological toxicity of 64 effluent samples collected from two factories producing konjac and glass were analyzed. It was found that the two types of wastewaters were not effectively dealt with the inner technology. Moreover, the acute biological toxicity evaluated by the bioluminescence inhibition to Vibrio fischeri revealed that ∼90% of the effluents were marked as toxic with bioluminescence inhibition higher than 50%. By applying a grey relational analysis (GRA) method to investigate the influential priorities of the effluent characteristics on biological toxicity, the results demonstrated that the top four influential factors on the bioluminescence inhibition were as follows: TN ≈ SO42− > Cl− > As ≈ Hg (for konjac-manufacturing effluents) and Zn > SO42− ≈ TN > As > Cl− (for glass-producing effluents). These results would be useful for fast recognizing the biological toxicity features of industrial effluents via evaluating the most influential parameters, and helpful for reducing the biological acute toxicity to protect the downstream wastewater treatment plant from abrupt collapse.