Enhanced toxicity of environmentally transformed ZnO nanoparticles relative to Zn ions in the epibenthic amphipod Hyalella azteca

Abstract

Transformations of ZnO NPs under different environmental conditions alters their toxicity to sediment-dwelling crustaceans.

Nanomaterial Transformations in the Environment: Effects of Changing Exposure Forms on Bioaccumulation and Toxicity

“…A lower toxicity of ZnS was also found for effects on plant growth, but not springtail reproduction in a study in which aged and pristine NMs were added to sewage sludge. [ 57 ] The lower toxicity of sulfidized compared to pristine ZnO in these two studies is in agreement with the finding of Poynton et al [ 58 ] However, in their study, exposure to phosphate transformed ZnO NMs resulted in comparable toxicity to the pristine NM, suggesting that different transformation reactions may have different effects on potency. In contrast to the general trend for Ag and ZnO, sulfidization of CuO NMs did not decrease toxicity to medeka embryos.…”

“…Toxicity to, e.g., survival, reproduction, morphology, microbial community composition/function of NM transformed in their core speciation generally cause in effects at higher concentration (e.g., NM potency is reduced) compared to pristine materials, although there are a small number of recorded exception this this general trend. [ 58,59 ] The manipulation of abiotic media components in contract produces a wider and more varied range of effects on NM bioavailability and toxicity, with the addition of organic matter both increasing and decreasing toxicity depending on the NM properties, the species and the chemistry of the exposure media. Overall, exposure concentrations were lower than those tested for speciation changes so that complete rescue of toxicity, where reductions were observed, cannot conclusively be established.…”

Nanoparticles: An Experimental Study of Zinc Nanoparticles Toxicity on Marine Crustaceans. General Overview on the Health Implications in Humans

“…Once introduced into the aquatic environment, the NPs undergo a series of processes (aggregation, sedimentation, biological degradation, and dissolution) that modify their destiny and lead to the formation of both potentially toxic aggregates and metal ions. These processes are influenced not only by multiple environmental factors, such as pH, salinity, and the presence of organic substances, but also by the structural characteristics of the particle, which include shape, size, morphological substructure of the substance (crystallinity, porosity, and surface roughness), chemical properties of the coarse material, solubility, dispersion state, area, and surface charge (115,(137)(138)(139).…”

“…Previous work related to the acute toxicity of ZnO NPs to other marine amphypod crustaceans. Wong et al (140) reported LC50 values of 1.19 mg/L for Elasmopus rapax exposed to ZnO NPs and 0.80 mg/L for those exposed to ZnSO 4 H 2 O. Poynton (115) reported that the LC50 values at 96 h for Hyalella azteca were lower than those obtained by us (0.08 mg/L for the ZnO NPs and 0.154 mg/L for ZnSO 4 ), placing this species as one of the most sensitive to ZnO NPs.…”

“…Khosravi-Katuli et al (113) suggested that the size of ZnO NPs can influence their toxic potential as well as the release of these NPs in the aquatic environment in presence of other contaminants. Effects of ZnO NPs on marine crustaceans have been studied using saltwater microcrustacean (114,115), linking time variable exposure (116), or different trophic level in multi NM system (117).…”