The importance of photochemical reactions in aquatic environments has become increasingly evident in the last fifty years. Here I discuss examples of: 1) direct and sensitized aqueous photoreactions of contaminants and natural compounds, including emerging materials such as nanomaterials and their composites with polymers; 2) the effects of photochemistry on microbial availability and toxicity of contaminants; 3) aquatic photochemical sources of atmospherically-important trace gases; 4) photobleaching and its impact on aquatic optics and the remote sensing of ocean color; 5) the role of photochemistry in biogeochemical cycles of carbon, nitrogen, and sulfur; and 6) links between photochemical and biological processes, including photoinactivation of pathogens and related indicators. A key focus is on the role played by the colored component of dissolved organic matter (CDOM) in controlling the availability of solar UV radiation in aquatic systems and initiating indirect photoreactions. Upon irradiation, CDOM and other natural substances (like nitrate) produce excited state and reactive oxygen species such as triplet states, singlet oxygen, superoxide/hydrogen peroxide and hydroxyl radicals that mediate indirect photoreactions in aquatic environments. I will discuss approaches to studying and modeling these intriguing photoreactions in the laboratory and field.

Interactions of light and chemical reactions in the aquatic environment: Kinetic and mechanistic aspects

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.