Toxicity and genotoxicity of organic and inorganic nanoparticles to the bacteria Vibrio fischeri and Salmonella typhimurium

Abstract

The present work aimed at evaluating the toxicity and genotoxicity of two organic (vesicles composed of sodium dodecyl sulphate/didodecyl dimethylammonium bromide-SDS/DDAB and of monoolein and sodium oelate-Mo/NaO) and four inorganic (titanium oxide-TiO₂, silicon titanium-TiSiO₄, Lumidot-CdSe/ZnS, and gold nanorods) nanoparticles (NP), suspended in two aqueous media (Milli Q water and American Society for Testing and Materials (ASTM) hardwater), to the bacteria Vibrio fischeri (Microtox test) and Salmonella typhimurium-his⁻ (Ames test with strains TA98 and TA100). Aiming a better understanding of these biological responses physical and chemical characterization of the studied NP suspensions was carried out. Results denoted a high aggregation state of the NP in the aqueous suspensions, with the exception of SDS/DDAB and Mo/NaO vesicles, and of nanogold suspended in Milli Q water. This higher aggregation was consistent with the low values of zeta potential, revealing the instability of the suspensions. Regarding toxicity data, except for nano TiO₂, the tested NP significantly inhibited bioluminescence of V. fischeri. Genotoxic effects were only induced by SDS/DDAB and TiO₂ for the strain TA98. A wide range of toxicity responses was observed for the six tested NP, differing by more than 5 orders of magnitude, and suggesting different modes of action of the tested NP.

Assessing the ecotoxicity of metal nano-oxides with potential for wastewater treatment

“…These results were in agreement with those reported by other authors, which till now have recorded no mutagenicity potential of different nanosize metal oxides (Al 2 O 3 , Co 3 O 4 , TiO 2 , ZnO, and Fe 3 O 4 ) to S. typhimurium and E. coli, both in the absence and presence of metabolic activation (Pan et al 2010;Pereira et al 2011;Lopes et al 2012;Szalay et al 2012). However, although the nano-TiO 2 tested in our study was smaller (<25 nm) than those used in previous studies, in Milli Q water (dilution medium in the Ames test), this nanooxide formed aggregates higher than 500 nm in diameter (Table 2), and this could have not favored the cellular uptake and the access to genetic material.…”

Biochemical and metabolic effects of a short-term exposure to nanoparticles of titanium silicate in tadpoles of Pelophylax perezi (Seoane)

“…perezi tadpoles which agrees with Pereira et al (2011) and Lopes et al (2012), who found no toxic effects of TiSiO 4 -NP to V. fisheri. Nevertheless, tadpoles' exposure to TiSiO 4 -NP revealed biochemical and metabolic effects.…”

“…Pelophylax perezi was used because inhabits permanent water bodies widespread in Iberian Peninsula and Southern France, is abundant, have not a protection status and is not endangered (Llorente and Arano, 1997). Titanium-based NP were chosen because are commonly used in several consumer products (Li et al, 2010), and, to our knowledge, only three studies were published with TiSiO 4 -NP (Pereira et al, 2011;Lopes et al, 2012;Nogueira et al, 2012).…”

“…TiSiO 4 -NP concentrations were selected according with data obtained by Pereira et al (2011) and Lopes et al (2012) and a preliminary assay (data not shown). A TiSiO 4 suspension of 20 mg/L (particle size <50 nm, 99.8% pure; Sigma-Aldrich, Darmstadt, Germany) was prepared and diluted in FETAX to obtain test concentrations.…”

Avaliação da genotoxicidade da nanopartícula de dióxido de titânio em juvenis de pampos, Trachinotus carolinus (Linnaeus, 1766), através de métodos citogenotóxicos

“…Nanopartículas são substâncias com pelo menos uma das dimensões medindo entre 1 e 100 nanômetros (nm) (MOORE, 2006;HANDY et al, 2008b;LOPES et al, 2012 A produção e a variedade destes produtos vêm crescendo rapidamente, assim como o crescimento da nanotecnologia, uma engenharia que abrange o desenvolvimento e a utilização destas substâncias (DAUGHTON, 2004;MOORE, 2006;HANDY et al, 2008;SINGH et al, 2009 A contaminação por nanopartículas nos organismos aquáticos pode ocorrer através da ingestão direta e também através da interface epitelial, tais como brânquias, órgão olfatório ou parede corporal. Além disso, organismos aquáticos desenvolvem processos de alta eficiência, como endocitose e fagocitose, para ingestão de partículas em escala nano e micrométrica (CANESI et al, 2008).…”