Vol. 11, Issue 4 (2022)

Author(s):
Pooja, Sushil Ahlawat, Reena Chauhan and Preeti Dhanker

Abstract:
Ground-water pollution through leaching of pesticides is one of the major issues. This in turn results in hazard to aquatic systems and drinking water resources. Diffused chemicals via leaching make groundwater vulnerable to pollution, hance making it unfit for proper usage. So, in order to safeguard the leaching losses as well pattern of diffusion, leaching behaviour of ready-premix formulation of Thiamethoxam + Lambda cyhalothrin was experimented in sandy loam soil at 50 g. a.i. ha^-1 (single dose) and 100 g a.i. ha^-1 (double dose) under various laboratory conditions following average annual rainfall of 440 mm. Residues were estimated at variable depths of soil and in leachates with the help of gas chromatography (GC-MS) equipped with electron capture detector (ECD). Method validation was done by performing recovery procedures at a series of different spiking levels ranging 0.01 - 0.10 mg kg^-1. Results obtained reported that the residues retained maximum in uppermost core i.e. 0 - 5 cm layer of soil with 83.23 and 81.54 per cent retention for both Thiamethoxam + Lambda cyhalothrin while residues reached below detectable level of 0.01 mg kg^-1 after 20 cm depth of soil at both doses. Since, no residues of combination product were observed in any leachate fraction. Hence, this combination product can be regarded safe for soil and ground water contamination.