Toxicity measurements in aqueous solution during ozonation of mono-chlorophenols

Chemical and toxicological evolution of the antibiotic sulfamethoxazole under ozone treatment in water solution

“…Moreover, for intermediate ozone dosing, the first oxidation products originate a considerable increase in toxicity which, in the case of P. subcapitata, leads to a growth inhibition of over 90% at pH 8. A toxicity increase in treated samples due to the formation of by-products that can cause greater toxicity than the parent compound has been observed previously [8,9,34]. Shang et al [34] reported a toxicity increase during the early stages of the ozonation of chlorophenols that could be attributed to the formation of chlorocatechols, chloromuconic acids and other hydroxylated or chlorinated compounds.…”

The impact of various ozone pretreatment doses on the performance of endogenous microbial communities for the remediation of oil sands process-affected water

“…An increase of bacterial inhibition towards Vibrio fischeri has been also reported during the ozonation of non-ionic surfactants while improved biodegradability of surfactants was observed (Ledakowicz et al, 2005). In addition, Shang et al (2006) revealed that oxidized chlorophenol intermediates induced more toxicity to pure bacteria and mixed microorganisms than parent compounds in the early stage of ozonation (<1 min) and then the inhibition gradually decreased until it disappeared after 6 min of reaction. For the treatment of OSPW, where biodegradability and toxicity are both of paramount concern, there is still need for more work to determine the optimal utilized dose of ozone for pretreatment prior to biodegradation.…”

Catalytic ozonation promoted by alumina-based catalysts for the removal of some pharmaceutical compounds from water

“…Literature extensively reports on the capacity of ozone technologies for the removal of a vast number of organic pollutants from water, including many pharmaceutical compounds [7]. However, when ozone is used alone, it does not often lead to high levels of mineralization and toxicity removal [7][8][9][10][11]. Mineralization can be improved by combining ozone with other agents (i.e., hydrogen peroxide or UV radiation) but this may result in a considerable increase in the treatment cost.…”