Chlorpyrifos degradation via photoreactive TiO2 nanoparticles: Assessing the impact of a multi-component degradation scenario.

Published

Journal Article

High concentrations of pesticides enter surface waters following agricultural application, raising environmental and human health concerns. The use of photoreactive nanoparticles has shown promise for contaminant degradation and surface water remediation. However, it remains uncertain how the complexity of natural waters will impact the photodegradation process. Here, we investigate the photoreactivity of titanium dioxide nanoparticles, the capability to degrade the pesticide chlorpyrifos, and the effect of and impact on bacteria during the photodegradation process. Loss of chlorpyrifos in solution resulted solely from photocatalytic oxidation, with 80% degradation observed after 24 h in our reactor, either in the presence or absence of bacteria. Degradation of chlorpyrifos to chlorpyrifos oxon and 3,5,6-trichloro-2-pyridinol was observed via LC/MS-MS and effectively modeled for the given reactor conditions. Bacterial inactivation occurred over 60 min and was not impacted by the presence of chlorpyrifos. The relative affinity of bacteria and chlorpyrifos for the nanoparticle surface decreased the amount of Reactive Oxygen Species (ROS) detected in the bulk by up to 94%, suggesting that ROS measurements in simplified systems may overestimate the reactivity of photoreactive nanoparticles in complex environments.

Full Text

Duke Authors

Cited Authors

  • Farner Budarz, J; Cooper, EM; Gardner, C; Hodzic, E; Ferguson, PL; Gunsch, CK; Wiesner, MR

Published Date

  • June 2019

Published In

Volume / Issue

  • 372 /

Start / End Page

  • 61 - 68

PubMed ID

  • 29254886

Pubmed Central ID

  • 29254886

Electronic International Standard Serial Number (EISSN)

  • 1873-3336

International Standard Serial Number (ISSN)

  • 0304-3894

Digital Object Identifier (DOI)

  • 10.1016/j.jhazmat.2017.12.028

Language

  • eng