Impacts of Chlorine on the Change of Chlorophyll Fluorescence Spectrum to Phaeodactylum tricornutum

Chlorine-containing disinfectants have been widely used all over the world to prevent COVID-19. However, little is known about potential risk of chlorine-containing in marine environment. Phaeodactylum tricornutum (P. tricornutum) a typical economic diatom, often as an effective biomarker ecotoxicology research. Here, present study has investigated effect different chlorine concentrations on photosynthesis P. by chlorophyll fluorescence spectroscopy. Results demonstrated that exposure promoted intensity at initial stage (24 h), suggesting large amount energy emitted form fluorescence. could not be detected under high (6.7 × 10−3, 1.0 10−2, 1.3 10−2 and 1.7 mg L−1) after 48 h, indicating had toxicity leading death microalgae. In addition, emission spectra were determined contain two distinct peaks representing core antenna photosystem II (685 nm) I complexes (710 control group. The peak value 685 nm significantly lower than 710 group, whereas treatments opposite. It can concluded microalgae regulate distribution excitation between photosystems ensure algae utilize light energy. result also found position blue shift NaClO treatments. excited 467 was 439 treatments, illustrating b more easily damaged antenna. Our findings are providing new insights into changing mechanism stress valuable data for assessment environments.