title: Biosorption and toxicity responses to arsenite (As[III]) in Scenedesmus quadricauda.
abstract: Toxicity and biosorption responses to arsenite (As[III]) were examined in a 96-h exposure study using Scenedesmus quadricauda, one of the most popular green algae distributed in freshwaters in China. Results indicated that the pH-dependent distribution of two arsenite species (H2AsO3(-) and H3AsO3) played an important role in biosorption and toxicity. The undissociated H3AsO3 was more toxic than its monoanionic H2AsO3(-) through comparison of algal cell numbers, chlorophyll-a contents, and algal ultrastructural changes observed with transmission electron microscopy. An effective biosorption of 89.0mgg(-1) at 100mgL(-1) As[III] was found in the treatments with an initial pH of 9.3 and 25.2μgg(-1) at 0.03mgL(-1) As[III] at an initial pH of 8.2 as a result of the predominant species of H2AsO3(-) under the ambient pH and Eh conditions. Our results imply that S. quadricauda may provide a new means for the removal of toxic arsenite species present in contaminated surface water.
authors: Environmental Science Institute, Zhejiang University, Hangzhou 310058, China. zjy@zju.edu.cn
authors: Jianying
authors: J
authors: Zhang
authors: Tengda
authors: T
authors: Ding
authors: Chunlong
authors: C
authors: Zhang
mesh_terms: D000327:Adsorption; D000838:Anions / Q000737:chemistry; D001151:Arsenic / Q000737:chemistry / Q000633:toxicity; D018053:Arsenites / Q000737:chemistry / Q000633:toxicity*; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D005618:Fresh Water / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D044444:Scenedesmus / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*
chemical_list: D000838:Anions; D018053:Arsenites; D014874:Water Pollutants, Chemical; D002734:Chlorophyll; C015001:arsenite; D001151:Arsenic; D000077194:Chlorophyll A
keywords: Algae; Arsenite species; Biosorption; Scenedesmus quadricauda; Toxicity