Effects of the ultraviolet filter oxybenzone on physiological responses in a red macroalga, Gracilaria vermiculophylla

Abstract

Oxybenzone is one type of ultraviolet (UV) filters that have been widely used as active ingredients in sunscreen and personal care products. The input of oxybenzone in the ocean through wastewater and swimmers has been a serious environmental pollution issue. Although oxybenzone has been reported as a toxicant to some marine animals and microalgae, its toxicity effect on macroalgae is still unknown. This study investigates the physiological responses of an aquaculture red macroalga, Gracilaria vermiculophylla, after twenty-days exposure to three different concentrations (0.1, 0.001 and 0.00001 mM) of oxybenzone. At the concentration of 0.1 mM, oxybenzone significantly decreased the growth rate, pigment content and photosynthetic rate, suggesting a high toxicity to G. vermiculophylla. At other two lower concentrations, oxybenzone induced no significant changes on physiological responses besides a decrease of pigment content at 0.001 mM. Our results revealed the toxicity and tolerance of oxybenzone on G. vermiculophylla.