Environmental Significance of PAH Photoproduct Formation: TiO2 Nanoparticle Influence, Altered Bioavailability, and Potential Photochemical Mechanisms

Lindsey St. Mary, Lisandra S. D. Trine, Courtney Roper, Jackson Wiley, Luca Craciunescu, Lia Sotorríos, Martin Paterson, Staci l. Massey Simonich, Martin McCoustra, Theodore B. Henry

Research output: Contribution to journalArticlepeer-review

Abstract

Interactions between polycyclic aromatic hydrocarbons (PAHs) and titanium dioxide (TiO2) nanoparticles (NPs) can produce unforeseen photoproducts in the aqueous phase. Both PAHs and TiO2-NPs are well-studied and highly persistent environmental pollutants, but the consequences of PAH-TiO2-NP interactions are rarely explored. We investigated PAH photoproduct formation over time for benzo[a]pyrene (BaP), fluoranthene (FLT), and pyrene (PYR) in the presence of ultraviolet A (UVA) using a combination of analytical and computational methods including, identification of PAH photoproducts, assessment of expression profiles for gene indicators of PAH metabolism, and computational evaluation of the reaction mechanisms through which certain photoproducts might be formed. Chemical analyses identified diverse photoproducts, but all PAHs shared a primary photoproduct, 9,10-phenanthraquinone (9,10-PQ), regardless of TiO2-NP presence. The computed reaction mechanisms revealed the roles photodissociation and singlet oxygen chemistry likely play in PAH mediated photochemical processes that result in the congruent production of 9,10-PQ within this study. Our investigation of PAH photoproduct formation has provided substantial evidence of the many, diverse and congruent, photoproducts formed from physicochemically distinct PAHs and how TiO2-NPs influence bioavailability and time-related formation of PAH photoproducts.
Original languageEnglish
Article number142384
JournalChemosphere
Volume360
Early online date24 May 2024
DOIs
Publication statusPublished - Jul 2024

Fingerprint

Dive into the research topics of 'Environmental Significance of PAH Photoproduct Formation: TiO2 Nanoparticle Influence, Altered Bioavailability, and Potential Photochemical Mechanisms'. Together they form a unique fingerprint.

Cite this