Removal of nonylphenol by earthworms and bacterial community change

Nonylphenol (NP), resulting from surfactants used in industrial and domestic products, is an endocrine disruptor, and its presence in the environment has garnered much concern. We assessed combinations of soil, compost, and sludge with living earthworms or earthworm casts for NP degradation and accompanying changes in bacterial community composition. NP could be removed in sludge and compost with living earthworms. The removal rate was higher with sludge than compost. The addition of earthworm casts to soil enhanced NP removal. We used a 454 pyrosequencing-based metagenomic approach to characterize NP-degrading associated bacterial communities and obtained 58,529 16S rRNA gene sequences from 25 experimental samples. Pearson correlation analysis revealed that the sequence frequency for 61 bacterial genera may be associated with NP degradation; 11 of these genera were reported to be involved with NP degradation. This is the first work to use living earthworms and earthworm casts for NP degradation and suggests a novel way to obtain bacteria with NP degradation ability. These results may have great potential for the effective removal of organic toxic chemicals in the environment.