Remediation of 1-Nitropyrene in Soil: A Comparative Study with Pyrene.

Nitrated polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants, which exhibits higher toxicity than their corresponding parent PAHs (PAHs). Recent studies demonstrated that the PAHs could represent major soil pollution, however the remediation of PAHs has been rarely reported. In this study, biological, physical, and chemical methods have been applied to remove 1-nitropyrene, the model PAH, in contaminated soil. A comparative study with pyrene has also been investigated and evaluated. The results suggest that the physical method with activated carbon is an efficient and economical approach, removing 88.1% and 78.0% of 1-nitropyrene and pyrene respectively, within one day. The zero-valent ion has a similar removal performance on 1-nitropyrene (83.1%), converting 1-nitropyrene to 1-aminopyrene in soil via chemical reduction and decreasing the mutagenicity and carcinogenicity of 1-nitropyrene. Biological remediation that employs scallion as a plant model can reduce 55.0% of 1-nitropyrene in soil (from 39.6 to 17.8 μg/kg), while 77.9% of pyrene can be removed by plant. This indicates that PAHs might be more persistent than corresponding PAHs in soil. It is anticipated that this study could draw public awareness of nitro-derivatives of PAHs and provide remediation technologies of carcinogenic PAHs in soil.