Prof. Laura MacManus-Spencer of Union College will present "The Secret Life of Sunscreens: Environmental Fate and Toxicity of the Active Ingredients in Sun Protection Products."

Organic UV filter chemicals (UVFCs) are the active ingredients in sun protection and other personal care products, designed to absorb harmful UV-A/B radiation. Annual global production of these chemicals exceeds 10 million tons, with more than four thousand tons of sunscreen entering the world's oceans each year. UVFCs are hydrophobic and lipophilic; they may bind to sediments in aquatic systems and permeate the skin upon topical application, and some act as endocrine disruptors. Many also undergo photochemical transformations upon exposure to sunlight, both in aquatic systems and on consumers' skin.

MacManus-Spencer will share results from student research at Union College on the sediment sorption, photolysis, and cellular toxicity of the organic UVFC Padimate O (octyl dimethyl para-aminobenzoic acid, or OD-PABA). Taking a holistic approach to its environmental fate and toxicity, the research has quantified the sorption capacities of four sediment samples with unique geochemical characteristics, investigated the transformation of Padimate O under natural and simulated sunlight, and assessed the cytotoxicity and sublethal cellular effects of Padimate O and its photoproducts.

Sponsored by the Chemistry Department.

Campus community only, please.