title: A comparison of fate and toxicity of selenite, biogenically, and chemically synthesized selenium nanoparticles to zebrafish (Danio rerio) embryogenesis.
abstract: Microbial reduction of selenium (Se) oxyanions to elemental Se is a promising technology for bioremediation and treatment of Se wastewaters. But a fraction of biogenic nano-Selenium (nano-Seb) formed in bioreactors remains suspended in the treated waters, thus entering the aquatic environment. The present study investigated the toxicity of nano-Sebformed by anaerobic granular sludge biofilms on zebrafish embryos in comparison with selenite and chemogenic nano-Se (nano-Sec). The nano-Sebformed by granular sludge biofilms showed a LC50value of 1.77 mg/L, which was 3.2-fold less toxic to zebrafish embryos than selenite (LC50=0.55 mg/L) and 10-fold less toxic than bovine serum albumin stabilized nano-Sec(LC50=0.16 mg/L). Smaller (nano-Secs; particle diameter range: 25-80 nm) and larger (nano-Secl; particle diameter range: 50-250 nm) sized chemically synthesized nano-Secparticles showed comparable toxicity on zebrafish embryos. The lower toxicity of nano-Sebin comparison with nano-Secwas analyzed in terms of the stabilizing organic layer. The results confirmed that the organic layer extracted from the nano-Sebconsisted of components of the extracellular polymeric substances (EPS) matrix, which govern the physiochemical stability and surface properties like ζ-potential of nano-Seb. Based on the data, it is contented that the presence of humic acid like substances of EPS on the surface of nano-Sebplays a major role in lowering the bioavailability (uptake) and toxicity of nano-Sebby decreasing the interactions between nanoparticles and embryos.
authors.affiliation: a UNESCO-IHE , Delft , The Netherlands.|b Institute of Environmental Sciences (CML), Faculty of Science , Leiden University , Leiden , The Netherlands.|c Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM , Marne-la-Vallée , France.
authors.forename: Joyabrata
authors.initials: J
authors.lastname: Mal
authors.affiliation: b Institute of Environmental Sciences (CML), Faculty of Science , Leiden University , Leiden , The Netherlands.
authors.forename: Wouter J
authors.initials: WJ
authors.lastname: Veneman
authors.affiliation: d Biofouling and Biofilm Process Section, Water and Steam Chemistry Division , Bhabha Atomic Research Centre , Kalpakkam , Tamil Nadu , India.|e Homi Bhabha National Institute , Anushakti Nagar , Mumbai , India.
authors.forename: Y V
authors.initials: YV
authors.lastname: Nancharaiah
authors.affiliation: a UNESCO-IHE , Delft , The Netherlands.|b Institute of Environmental Sciences (CML), Faculty of Science , Leiden University , Leiden , The Netherlands.
authors.forename: Eric D
authors.initials: ED
authors.lastname: van Hullebusch
authors.affiliation: b Institute of Environmental Sciences (CML), Faculty of Science , Leiden University , Leiden , The Netherlands.|f RIVM-National Institute of Public Health and the Environment, Center for Safety of Substances and Products , Bilthoven , The Netherlands.
authors.forename: Willie J G M
authors.initials: WJ
authors.lastname: Peijnenburg
authors.affiliation: b Institute of Environmental Sciences (CML), Faculty of Science , Leiden University , Leiden , The Netherlands.
authors.forename: Martina G
authors.initials: MG
authors.lastname: Vijver
authors.affiliation: a UNESCO-IHE , Delft , The Netherlands.|g Department of Chemistry and Bioengineering , Tampere University of Technology , Tampere , Finland.
authors.forename: Piet N L
authors.initials: PN
authors.lastname: Lens
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D001673:Biodegradation, Environmental; D047108:Embryonic Development / Q000187:drug effects*; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D010316:Particle Size; D011108:Polymers; D020887:Selenious Acid / Q000737:chemistry / Q000633:toxicity*; D012643:Selenium / Q000737:chemistry / Q000633:toxicity*; D012710:Serum Albumin, Bovine; D012722:Sewage / Q000737:chemistry / Q000382:microbiology; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*; D015027:Zebrafish / Q000196:embryology*
chemical_list: D011108:Polymers; D012722:Sewage; D014874:Water Pollutants, Chemical; D012710:Serum Albumin, Bovine; D020887:Selenious Acid; D012643:Selenium
keywords: Biogenic nanomaterials; EPS; nanotoxicology; selenium bioremediation; zebrafish