Do transformation products contribute to mixture toxicity

Transformation products (TPs) and oxidation byproducts have been found in water that has undergone oxidative treatment, however, only a few of them are currently regulated around the world. The traditional process of identifying, isolating and quantifying hazardous transformation products and oxidation byproducts is costly and time consuming; therefore, we propose to develop a tiered approach for screening organic micropollutants for their potential to form toxicologically relevant transformation products that combines in parallel bioanalytical assessment and identification and quantification of the formed transformation products. Laboratory experiments were conducted with a range of compounds some of which were previously detected at an Australian Wastewater Treatment Plant whose effluent is fed into an Advanced Water Recycling Plant (AWRP). Selected chemicals were pesticides atrazine, hexazinone, haloxyfop, endocrine disrupting compound bisphenol A, X-ray contrast media iopromide, pharmaceuticals carbamazepine, diclofenac, and antibiotic sulfamethoxazole. Benchscale experiments were performed in RO water collected from the AWRP. The transformation processes was tested with different ozone doses (0 200 μM). The bioanalytical equivalent concentrations were compared with the parent compound concentrations and only if these did not correlate linearly, it would be an indication that more or equally potent TPs were formed during the oxidation process. Seminar Invitation