In fact, changes in microbial metabolites can directly reflect microbial responses to environmental stimuli. Metabolomics technology as a new set of tools has been widely used in the evaluation of the toxicity of nanomaterials . For instance, Zhao et al. utilized gas chromatography-mass spectrometry (GC-MS) based on metabolomics to evaluate the toxicity of copper nanoparticles . Ratnasekhar et al. used metabolomics to study the perturbations in the metabolome of Caenorhabditis elegans exposed to titanium dioxide nanoparticles .