Toxicity of perfluooctane sulfonate (PFOS) and perfluorobutane sulfonate (PFBS) to Scenedesmus obliquus: Photosynthetic characteristics, oxidative damage and transcriptome analysis. (15th December 2022)

• Record Type: Journal Article
• Authors: Xue, Xingyan; Gao, Ning; Xu, Fuliu
• Is Part Of: Environmental pollution. Volume 315(2022)
• Publication Date: 2022-12-15
• Subjects: PFOS -- PFBS -- Scenedesmus obliquus -- Chlorophyll fluorescence -- Transcriptome; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2022.120397
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: With the wide application as an alternative for perfluorooctane sulfonate (PFOS), perfluorobutane sulfonate (PFBS) has been frequently detected in the aquatic environment. However, the aquatic toxicity of PFBS is still poorly understood. The present work studied the aquatic toxicity of PFBS using freshwater algae Scenedesmus obliquus ( S. obliquus ) as indicator, and the toxicity of PFOS was also examined for comparison. The results showed that PFBS exhibited much lower toxicity to S. obliquus than PFOS. The EC50 value was higher than 1800 mg L −1 after 7 days of exposure to PFBS. By contrast, a much lower EC50 value of 136.69 mg L −1 was obtained for PFOS. Photosynthetic efficiency analyzed by chlorophyll fluorescence also verified that PFOS induced a higher toxic effect on the algae than PFBS. The malondialdehyde, catalase and superoxide dismutase results indicate that PFOS exposure led to the accumulation of ROS, which caused oxidative damage to the algae, thereby resulting in the inhibition in the growth and photosynthesis of the algae. Furthermore, transcriptome analysis indicates that the significant down-regulation of key genes related to photosynthesis induced by PFOS was the fundamental mechanism for the inhibition in photosynthetic efficiency and biomass growth of S. obliquus . Graphical abstract: Image 1 Highlights: The aquatic toxicity of PFBS and PFOS was compared using algae S. obliquus . PFBS exhibited much lower toxicity to S. obliquus than PFOS. PFOS significantly inhibited the algae growth and photosynthetic efficiency. PFOS exposure accumulated ROS and caused oxidative damage to S. obliquus . PFOS significantly down-regulated the expression of genes related to photosynthesis.