Study of the effect of nanoparticles Cu, Zn and Mo on vermiculture to create new technologies for bioremediation of contaminated soils

Abstract

One of the manifestations of the toxic effect of nanoparticles on living organisms is the ability of nanoparticles to generate reactive oxygen species. At the same time, antioxidant protection enzymes should be considered as biomarkers of such an effect. In our study, we used nanoparticles (NPs) of Cu, Zn, Mo at concentrations of 50, 200, 500 and 1000 mg/kg of dry soil. Standardized soil of 70 % quartz sand, 20 % kaolin, and 10 % crushed peat was used as a substrate. The test objects were E. fetida worms. We obtained the following results: SOD activity predominantly decreased (to –69.5 % at 200 mg/kg nanoparticles Cu), the CAT activity increased (up to 110 % at a dose of 1000 mg/kg nanoparticles Mo). The MDA content was higher than the control at 500–1000 mg/kg nanoparticles Zn and Mo. In accordance with the revealed effects in the description of the comparative action of Cu, Zn, Mo nanoparticles on the antioxidant system, it was found that their toxicity to E. fetida progressively decreased in the order: Mo → Zn → Cu. Thus, we have shown the possibility of using vermiculture in the development of technologies and methods for the restoration of soils contaminated with metals, since worms have the ability to tolerate oxidative stress, activating defense mechanisms.