Role of ROS generation in acute genotoxicity of azoxystrobin fungicide on freshwater snail Lymnaea luteola L.

Azoxystrobin (AZ) is an aryloxy pyrimidine fungicide extensively applied in the agriculture field all over the world. There is a little information about the ecotoxicity of AZ fungicide on the freshwater snail Lymnaea luteola (L. luteola). The present study investigated the toxic effect of AZ fungicide on L. luteola by using various measures. We determined the mean LC50 value-96 h of AZ fungicide (0.79 mg/L) for L. luteola, in a static system. Based on this value, three sublethal concentrations, viz., I (0.079 mg/L), II (~ 0.40 mg/L), and III (~ 0.53 mg/L), were determined. The snails were exposed to these three concentrations of AZ fungicide for 96 h, and hemolymph and digestive glands were collected after 24 and 96 h for assessment of oxidative stress, apoptosis, and histological and genotoxic changes. The induction of intracellular reactive oxygen species (ROS) and apoptosis in hemocyte cells was increased in a dose- and time-dependent manner. It was observed that lipid peroxide (LPO) and glutathione S transferase (GST) were increased, and glutathione and superoxide dismutase decreased in digestive glands. A similar trend was observed for the DNA damage as measured in terms of the percentage of tail DNA and olive tail moment in digestive gland cells. This study showed the collective use of oxidative stress, histological, and genotoxicity parameters in in vivo laboratory studies using snails that are useful for screening the toxic potential of environmental contaminants such as AZ fungicide.Graphical abstract.

Synthesis and Characterization of Amorphous Iron Oxide Nanoparticles by the Sonochemical Method and Their Application for the Remediation of Heavy Metals from Wastewater.

Nanoparticles have gained huge attention in the last decade due to their applications in electronics, medicine, and environmental clean-up. Iron oxide nanoparticles (IONPs) are widely used for the wastewater treatment due to their recyclable nature and easy manipulation by an external magnetic field. Here, in the present research work, iron oxide nanoparticles were synthesized by the sonochemical method by using precursors of ferrous sulfate and ferric chloride at 70 °C for one hour in an ultrasonicator. The synthesized iron oxide nanoparticles were characterized by diffraction light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), electron diffraction spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM). The FTIR analysis exhibits characteristic absorption bands of IONPs at 400-800 cm-1, while the Raman spectra showed three characteristic bands at 273, 675, and 1379 cm-1 for the synthesized IONPs. The XRD data revealed three major intensity peaks at two theta, 33°, 35°, and 64° which indicated the presence of maghemite and magnetite phase. The size of the spherical shaped IONPs was varying from 9-70 nm with an average size of 38.9 nm while the size of cuboidal shaped particle size was in microns. The purity of the synthesized IONPs was confirmed by the EDS attached to the FESEM, which clearly show sharp peaks for Fe and O, while the magnetic behavior of the IONPs was confirmed by the VSM measurement and the magnetization was 2.43 emu/g. The batch adsorption study of lead (Pb) and chromium (Cr) from 20% fly ash aqueous solutions was carried out by using 0.6 mg/100 mL IONPs, which exhibited maximum removal efficiency i.e., 97.96% and 82.8% for Pb2+ and Cr ions, respectively. The fly ash are being used in making cements, tiles, bricks, bio fertilizers etc., where the presence of fly ash is undesired property which has to be either removed or will be brought up to the value of acceptable level in the fly ash. Therefore, the synthesized IONPs, can be applied in the elimination of heavy metals and other undesired elements from fly ash with a short period of time. Moreover, the IONPs that have been used as a nanoadsorbent can be recovered from the reaction mixture by applying an external magnetic field that can be recycled and reused. Therefore, this study can be effective in all the fly ash-based industries for elimination of the undesired elements, while recyclability and reusable nature of IONPs will make the whole adsorption or elimination process much economical.