Toxicity assessment of wastewater from the industrial parks along Yangtze River, China, using a battery of bioassays

Bioassays, as an addition to physico-chemical water quality evaluation, can provide information on toxic effects of pollutants present in the water. In this study, a broad evaluation of environmental health risks from industrial wastewater along the Yangtze River, China, was conducted using a battery of bioassays. A total of 10 polycyclic aromatic hydrocarbons (PAHs), which were identified as potential major toxic chemicals of concern were measured in the samples of W, J, and T wastewater treatment plants. Toxicity tests showed that the wastewater treatment processes were effective at lowering acetylcholinesterase (AChE) inhibition, HepG2 cells cytotoxicity, estrogenic effect in T47D-Kbluc cells, DNA damage of Euglena gracilis and mutagenicity of Salmonella typhimurium in analyzed wastewater samples. However, the potential harm to the aquatic organisms has remained. Based on the health risk assessment model, the PAHs risk index of wastewater from the industrial parks along the Yangtze River was below 1, indicating that the PAHs in wastewater were less harmful to human health through skin contact or respiratory exposure. Overall, biological toxicity tests used in this study provide good basis for the health risk assessment of industrial wastewater and a scientific reference for the optimization and operation of the treatment process.