Fate and effects of nonylphenol in the presence of the cyanobacteriumMicrocystis aeruginosa

Abstract

Interactions of nonylphenol (NP), a toxic and oestrogenic degradation product of widely used non-ionic surfactants, with the cyanobacterium Microcystis aeruginosa were studied. Batch cultures were incubated for 10 days with NP concentrations between 10 and 570 nM. NP was removed more quickly in the presence of M. aeruginosa (half-life 2.7-5.2 days) than in its absence (half-life 6.7-10.2 days) at all concentrations tested. At the end of the experiment, NP could not be found in the biomass, so the biotic removal is due to uptake and chemical transformation, and not to physical binding on the cells. The observed effective concentrations, EC 50 and EC 20 , were 0.45 and 0.25 μM, respectively. Therefore, NP is expected to have toxic effects on M. aeruginosa only in very contaminated surface waters. However, for concentrations that go far beyond environmental levels, cyanobacteria are able to cope with NP toxicity by internalising the compound in a less toxic form. Therefore, the presence of cyanobacteria may increase the rate of NP removal from the aquatic environment.

Removal and fate of endocrine disruptors chemicals under lab-scale postreatment stage. Removal assessment using light, oxygen and microalgae

“…The algae may produce some secretions which after irradiation can produce hydroxyl radicals that can enhance the BPA degradation (Peng et al, 2006). The OP and t-NP removal can be improved by the cyanobacteria cells, this effect was enhanced at low concentrations of OP and t-NP (Stoichev et al, 2010). Whereas, the works developed by Corvini et al, (2006) proposed a mechanism for degradation of nonylphenols with bacterial strain Sphingomonas sp.…”