Daphnia magna mortality when exposed to titanium dioxide and fullerene (C₆₀) nanoparticles

Abstract

Nanoparticles (1-100 nm) comprise the latest technological advances designed to do everything from absorb environmental toxins to deliver drugs to a target organ. Recently, however, they have come under scrutiny for the potential to cause environmental damage. Because compounds in this miniature size range have chemical properties that differ from those of their larger counterparts, nanoparticles deserve special attention. Our main objective was to assess the potential impact that nanoparticles may have on release into aquatic environments. We prepared titanium dioxide (TiO2) and fullerene (C60) nanoparticles by filtration in tetrahydrofuran or by sonication. Daphnia magna were exposed to the four solutions using U.S. Environmental Protection Agency 48-h acute toxicity tests. Images of the particle solutions were recorded using transmission-electron microscopy, and the median lethal concentration, lowest-observable-effect concentration, and no-observable-effect concentration were determined. Exposure to filtered C60 and filtered TiO2 caused an increase in mortality with an increase in concentration, whereas fullerenes show higher levels of toxicity at lower concentrations. Exposure to the sonicated solutions caused varied mortality. Understanding the potential impacts of nanoparticles will help to identify the most appropriate nanotechnology to preserve the aquatic environment while advancing medical and environmental technology.

Effects of suspended multi-walled carbon nanotubes on daphnid growth and reproduction

“…It has been reported that toxic endpoints observed in many of those assays could be attributed to THF decomposition products (Henry et al 2007). In their D. magna bioassays with nanoparticulate TiO 2 and C 60 , Lovern and Klaper (2006) used THF, but constructed their method to evaporate THF before organism exposure. In their statistical analysis, there was no significant difference between toxicity of TiO 2 solutions that had once contained THF and solutions that never had.…”

Behavioral and Physiological Changes inDaphnia magnawhen Exposed to Nanoparticle Suspensions (Titanium Dioxide, Nano-C60, and C60HxC70Hx)

“…Nanoparticles were prepared and characterized according to Lovern and Klaper (2006). Briefly, because carbon particles are typically hydrophobic, 20mg of each type of nanoparticle (99.5% purity) (Alfa Aesar, Ward Hill, MA, U.S.A.) were placed into 200mL of tetrahydrofuran (THF), sparged with nitrogen, and left to stir overnight.…”

Toxicity, bioaccumulation and biomagnification of silver nanoparticles in green algae (Chlorellasp.), water flea (Moina macrocopa), blood worm (Chironomusspp.) and silver barb (Barbonymus gonionotus)

“…Recently, most research has remained focused on the toxicity of AgNPs on bacteria or organisms at a higher trophic level (Miao et al, 2009;Lovern and Klaper, 2006), with little research studying the effect of AgNPs on the food chain, bioaccumation and biomagnification. An implication is that AgNPs accumulated by primary producers such as phytoplankton or algae could then be available to the next level of predators in the food chain, which could lead to broader ecological effects.…”