Toxicity of Quantum Dots and Cadmium Salt to Caenorhabditis elegans after Multigenerational Exposure

Abstract

To fully understand the biological and environmental impacts of nanomaterials requires studies which address both sub-lethal endpoints and multigenerational effects. Here we use a nematode to examine these issues as they relate to exposure to two different types of quantum dots, core (CdSe) and core-shell (CdSe/ZnS), and to compare the effect to those observed after cadmium salt exposures. The strong fluorescence of the core-shell QDs allowed for the direct visualization of the materials in the digestive track within a few hours of exposure. Multiple endpoints, including both developmental and locomotive, were examined at QD exposures of low (10 mg/L Cd), medium (50 mg/L Cd), and high concentrations (100 mg/L Cd). While the core-shell QDs showed no effect on fitness (lifespan, fertility, growth, and three parameters of motility behavior), the core QDs caused acute effects similar to those found for cadmium salts suggesting that biological effects may be attributed to cadmium leaching from the more soluble QDs. Over multiple generations, we commonly found that for lower life-cycle exposures to core QDs the parents response was generally a poor predictor of the effects on progeny. At the highest concentrations, however, biological effects found for the first generation were commonly similar in magnitude to those found in future generations.

Impacts of mercury exposure on life history traits of Tigriopus japonicus: Multigeneration effects and recovery from pollution

“…This is in agreement with a previous study where toxicity of quantum dots and cadmium salt was investigated in the nematode Caenorhabditis elegans under multigenerational exposure (Contreras et al, 2013). These results suggest that over generations, aquatic animals can show more potential to acclimate to lower metal exposure rather than higher concentrations.…”

C. elegans-on-a-chip for in situ and in vivo Ag nanoparticles’ uptake and toxicity assay

“…5a,b emphasizes the usability of two parameters, body size and fluorescence intensity, as specific and quantitative indicators for the assessment of AgNPs because the only silver nanoparticle significantly influences both parameters. Given that the concentration (0.01 mg/L) is much lower than that used in the previous studies5253, these indicators also possess a sensitivity in addition to the selectivity. These results demonstrate that the C. elegans -on-a-chip loaded with N2 and CL2122 strains has a potential applicability for the detection of nanoparticles or assay of their toxicities using multiple parameters including the body size, the migration distance and the fluorescence from a specific gene overexpression.…”

Oxidative injury induced by cadmium sulfide nanoparticles in A549 cells and rat lungs

“…Exposure to CdS NPs may have greater toxicity and potential health hazards and may cause serious damage to multiple systems (Contreras et al, 2013;Li et al, 2009). The respiratory tract is one of the main routes by which CdS NPs enter the body to produce damage to the lung tissue (Kovacic & Somanathan, 2010).…”