In Vitro Testing

Given the diverse types of nanoparticles (NPs) present in the market, in vitro techniques have been recommended as a tool for environmental risk assessment (ERA) of NPs. This chapter reviewed recent data on the use of in vitro toxicity testing with cells of aquatic vertebrate (fish) and invertebrate (bivalve mollusc) species, focusing on cells from marine mussels Mytilus galloprovincialis, a worldwide sentinel species of pollution and target for nanoparticle toxicity. Most studies have been focused on NPs such as Au, ZnO, SiO₂, TiO₂, CdS, Ag, and CuO NPs. Screening tests allowed the classification of their relative toxicity and the identification of main properties that influence their toxicity, which was primarily driven by the chemical composition and behaviour of NPs in exposure media. Other factors such as size, mode of synthesis, shape and presence of additives also influenced NPs toxicity. At sublethal doses, modes of action of CdS, Ag, and CuO NPs involve oxidative stress, genotoxicity, lysosomal activation, alterations in membrane transport and immunostimulation, Overall, in vitro results generally agree well with effects found in vivo, suggesting that in vitro tests can be used as a rapid, reproducible, and sensitive tool for ERA of nanomaterials in the aquatic environment.