In this study, major toxicants in pigment wastewaters (i.e. raw wastewater and effluent) were determined by toxicity identification evaluations (TIEs), and changes in their toxicities due to combined gamma-ray (γ-ray) and ozone treatments were evaluated. From TIE results using Daphnia magna, Cr(VI) and o-toluidine were identified as major toxicants in the raw wastewater with concentrations of 2.47 and 25.3 mg l-1, respectively. This was confirmed by subsequent spiking and mass balance approaches. For effluent, TIE results suggested that organic anions were likely responsible for the observed toxicities. Toxicity reduction tests showed that γ-rays with ozone treatment after coagulation was more efficient in reducing toxicities in the raw wastewater (3.9-2.0 TU) than γ-ray treatment alone (3.9-3.1 TU). For pigment effluent, γ-ray/O3 treatment resulted in a complete removal of the acute toxicity.
- Daphnia magna
ASJC Scopus subject areas
- Environmental Engineering
- Environmental Chemistry
- Health, Toxicology and Mutagenesis