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The heavy metal speciation analysis in sediments helps us understand and evaluate essential and unavoidable issues in terms of both health and environmental hazards imposed by these metals in our lives. Analyzing the total content of heavy metals enables us to understand only the quantity of the contaminants. To understand the different species or the chemical forms of heavy metals available in the sediments, we must study their speciation. Speciation studies help us determine their possible sources as well as their environmental stability in terms of availability to plants and other organisms. The heavy metals in this study were specified using four-stage sequential extraction, also known as the BCR technique. This study mainly highlights the quantification of metal contamination of Cu, Zn, Pb, Ni, Cd & Cr, and chemical forms as species in sediment samples collected from different Pune District, Maharashtra sites. Heavy metal contamination from the collected samples was analyzed with the use of flame atomic absorption spectrometry. This study indicated that Zn and Ni are among the most abundant metals in the sediment samples; however, Cu and Cd belong to the least abundant category. The oxidizable and residual forms (immobile and cannot be used by the organisms readily) appeared dominant for most heavy metals. Very significant differences were observed in the speciation of heavy metals from sample to sample, which was probably due to differences in water/soil composition and the agrochemicals like pesticides, weedicides, and fertilizers used in agricultural practices; the wastewater generated from different pharmaceuticals, chemical processing and manufacturing industries as well as the improper wastewater treatment methods. [ABSTRACT FROM AUTHOR]

The field experiments were carried out to evaluate the bio-efficacy and residue dynamics of Polyoxin D Zinc salt 5% SC in grape during 2014–2015 and 2015–2016 at ICAR-National Research Centre for Grapes, Pune. Polyoxin D Zinc salt 5% SC @ 600 ml ha-1 gave the best control of the disease, both in the leaves and bunches with a percent disease control of 56.4 and 75.7 respectively, as compared to untreated control. The percent disease control of the test fungicide Polyoxin D Zinc salt 5% SC @ 600 ml ha-1 was superior to all the triazoles viz. Flusilazole 40 EC, Hexaconazole 5 EC and Myclobutanil 10 WP, used in the study. The yield data reflected a similar trend wherein the maximum percent increase in yield was observed in case of Polyoxin D Zinc salt 5% SC @ 600 ml ha-1 i.e. 57.47 as compared to untreated control. However, all the triazoles manifested a higher percent increase in yield as compared to the lowest dose of the test fungicide i.e. 200 ml ha-1. For the detection and quantification of polyoxin D residue in grape, we have developed an efficient and effective analytical method, using liquid chromatography-tandem mass spectrometry (LC-MS/MS), in field treated samples. The residue data had excellent fit to 1st+1st order models giving r2 value of >0.99 with a half-life (t1/2) 8.0 days for recommended dose and 14.5 days for double dose. These findings are useful for effective disease management in grape crop amalgamated with food safety and consumer satisfaction. [ABSTRACT FROM AUTHOR]