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Salzberg Chemistry Seminar: Prof. Laura MacManus-Spencer

  • Date
    Mon, Nov 18

    12:00 PM — 1:00 PM

    Marshak Hall
    160 Convent Avenue

    Marshak Hall, 1027

    p: 212.650.8402


  • Event Details

    What happens to that sunscreen cream after your use it?

    Prof. Laura MacManus-Spencer of Union College in Schenectady, NY will present the topic, "What happens to that suncreen cream after you use? - the photochemical fate of sunscreen chemicals in the aquatic environment."

    Ultraviolet (UV) filter chemicals are the active ingredients used in sunscreens, lotions, lip balms and other personal care products intended for protection from UV light from
    the sun. Though UV filter chemicals are designed to remain photostable, several are known to degrade upon exposure to UV light, which has implications both for their effectiveness in sunscreen products and for their fate in the aquatic environment. In this study, the aqueous photolysis of several UV filter chemicals is investigated; this presentation will focus on two commonly used chemicals –
    octyl methoxycinnamate (Octinoxate) and octyldimethyl para-aminobenzoic acid (Padimate O). Experiments are conducted under natural and simulated sunlight to determine the kinetics and mechanism of direct photolysis
    and the importance of indirect photolysis. The relative importance of indirect photolysis is investigated by conducting photolysis experiments in the presence of varying concentrations of well characterized humic and
    fulvic acids. In addition, the pH dependence of direct photolysis is investigated. Liquid chromatography – mass spectrometry is used to identify the products of direct photolysis. The data obtained in this study may be used to
    assess the fates of UV filter chemicals in the aquatic environment and to make informed decisions about their use in consumer products.