Acute and chronic response of Daphnia magna exposed to TiO2 nanoparticles in agitation system.

Acute and chronic response of Daphnia magna exposed to TiO2 nanoparticles in agitation system.

Bulletin of environmental contamination and toxicology (2014-05-23)

Ki-Tae Kim, Stephen J Klaine, Sang D Kim

ABSTRACT

Aquatic toxicity of titanium dioxide nanoparticles (TiO2 NPs) to Daphnia magna was characterized using a completely stirred bioassay system intended to keep particles in suspension thereby maintaining a consistent exposure. The 48-h LC50 was 4.5 mg/L TiO2 NPs, whereas LC50 values for 7 and 14-days exposures were 2.7 and 1.9 mg/L, respectively. An exposure of 1.5 mg/L over a 21-days exposure resulted in significant reductions in fecundity. While reproduction was initially reduced in the 0.5 and 1.0 mg/L exposures, it recovered and was similar to the control by 21 days. For reproduction inhibition, NOEC was 1.0 mg/L. Exposure to 2.5 mg/L TiO2 NPs resulted in 40 % of the organisms failing to become gravid; all surviving organisms exposed to 5.0 mg/L failed to become gravid. The increased sensitivity was due to the refinement in the bioassay system that kept NP in suspension resulting in consistent exposure concentrations.

MATERIALS

Product Number

Brand

Product Description

30-2730

Sigma-Aldrich

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718467

Sigma-Aldrich

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Sigma-Aldrich

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Sigma-Aldrich

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Titanium, sphere, 200pcs, diameter 3mm, 99.6+%

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Titanium, tube, 100mm, outside diameter 6.35mm, inside diameter 4.57mm, wall thickness 0.89mm, annealed, 99.6+%

GF38954076

Titanium, rod, 200mm, diameter 6mm, annealed, 99.6+%

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Titanium, tube, 100mm, outside diameter 12.7mm, inside diameter 10.9mm, wall thickness 0.9mm, annealed, 99.6+%

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Titanium, wire reel, 500m, diameter 0.25mm, as drawn, 99.6+%

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Titanium, wire reel, 2m, diameter 0.5mm, as drawn, 99.99+%

GF18195857

Titanium, wire reel, 5m, diameter 0.5mm, as drawn, 99.99+%

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Titanium, wire reel, 1m, diameter 0.75mm, as drawn, 99.6+%

GF04455299

Titanium, wire reel, 200m, diameter 0.05mm, hard, 99.8%

GF33302832

Titanium, wire reel, 1m, diameter 1.0mm, annealed, 99.6+%

GF79315027

Titanium, wire reel, 5m, diameter 0.25mm, annealed, 99.6+%

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GF96944923

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