Skip to Main content Skip to Navigation
Journal articles

Formation of environmentally persistent free radicals and reactive oxygen species during the thermal treatment of soils contaminated by polycyclic aromatic hydrocarbons

Abstract : Environmentally persistent free radicals (EPFRs) are emerging contaminants of increasing concern due to their toxicity for life and ecosystems, yet their formation, behavior and fate are poorly known. In particular, there is actually no knowledge on the formation of those radicals during the thermal treatment of soils containing polycyclic aromatic hydrocarbons. Such knowledge is important because thermal treatment is a remediation method used to decontaminate soils by removing and degrading PAHs. Here, we studied the formation of radicals in three types of cultivated soils, bauxite soil, fluvo-aquic soil and chernozem soil, artificially contaminated by benzo[a]pyrene, during thermal treatment from 100 to 200 °C for 1 h, using electron paramagnetic resonance. Results show spins densities of radicals up to of 2.079 × 10 17 spins/g for bauxite soil, 1.481 × 10 17 spins/g for fluvo-aquic soil and 8.592 × 10 16 spins/g for chernozem soil at 175 °C. The formed radicals exhibited multiple decays during their observable time and the shortest 1/e lifetimes of radicals up to 757.58 h. These findings are strengthened by EPFR-induction of reactive oxygen species (ROS), O 2 ·− and · OH, which increased in concentrations from 100 to 200 °C. Overall, our results demonstrates for the first time that thermal treatment of PAHs-contaminated soils induces the formation of EPFRs and suggests that thermal treatment might not be a fully clean remediation method for soils as thermal treatment creates new contaminants.
Document type :
Journal articles
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-02884027
Contributor : Eric Lichtfouse <>
Submitted on : Monday, June 29, 2020 - 3:58:23 PM
Last modification on : Wednesday, July 1, 2020 - 3:03:19 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : 2020-09-29

Please log in to resquest access to the document

Identifiers

Collections

Citation

Jinbo Liu, Hanzhong Jia, Kecheng Zhu, Song Zhao, Eric Lichtfouse. Formation of environmentally persistent free radicals and reactive oxygen species during the thermal treatment of soils contaminated by polycyclic aromatic hydrocarbons. Environmental Chemistry Letters, Springer Verlag, 2020, 18, pp.1329 - 1336. ⟨10.1007/s10311-020-00991-1⟩. ⟨hal-02884027⟩

Share

Metrics

Record views

61