Time dependent sorption behavior of dinotefuran, imidacloprid and thiamethoxam

Abstract

Dinetofuran (DNT), imidacloprid (IMD) and thiamethoxam (THM) are among the neonicotinoid insecticides widely used for managing insect pests of agricultural and veterinary importance. Environmental occurrence of neonicotinoid in post-application scenario poses unknown issues to human health and ecology. A sorption kinetic study provides much needed information on physico-chemical interaction of neonicotinoid with soil material. In this research study, time-dependent sorption behavior of DNT, IMD and THM in vineyard soil was studied. Sorption kinetics studies were conducted over a period of 96 hours with sampling duration varying from 0, 2, 4, 8, 12, 24, 60 and 96 hours. All three neonicotinoids exhibited very low sorption potential for the soil investigated. Overall percent sorption for all three neonicotinoids was below 20.04 ± 2.03% with highest percent sorption being observed for IMD followed by DNT and THM. All three neonicotinoids are highly soluble with solubility increasing with IMD < THM < DNT. Although, DNT has the highest solubility among all three neonicotinoids investigated, it exhibited higher percent sorption compared to THM, indicating factors other than solubility influenced the sorption kinetics. Low sorption potential of neonicotinoids indicates greater leaching potential with regard to groundwater and surface water contamination.

Sublethal effects of imidacloprid exposure on Spalangia endius, a pupal parasitoid of filth flies

“…Liquid or solids in the used fly media may have removed imidacloprid in or on the parasitoids to levels that did not reduce fly killing and parasitoid reproduction. Imidacloprid is highly soluble in water (Kurwadkar et al 2013) and adsorbs to organic matter (Cox et al 1998). In contrast, when imidacloprid remains on a female, it may be absorbed through non-sclerotized parts of the insect's cuticle, as seen in fleas (Mehlhorn et al 1999); or females may also consume it as they groom because grooming frequently involves pulling the antennae and legs through the mouth.…”

Ultrasonic-assisted modification of a novel silkworm-excrement-based porous carbon with various Lewis acid metal ions for the sustained release of the pesticide thiamethoxam

“…The TM-release kinetics performance was tested according to a previous test method reported in the literature. 21,22 Before measurement, the TM adsorbed the PCSE and LAMI-modied PCSEs samples were dried in a vacuum oven at 40 C for 5 h. Then, the above samples were weighed and placed in a dialysis bag with 20.0 mL water. The dialysis bag was put in a 250 mL conical ask lled with 100.0 mL water.…”

Effect of Growing Groundcover Plants in a Vineyard on Dissipation of Two Neonicotinoid Insecticides

“…In our study, the phenomena could be observed in our bare land control, showing a high amount of dinotefuran retained in the surface soil right after application, and in the imidacloprid retained almost throughout the experiment. The different distribution of the two neonicotinoids in the bare land control could be explained by the different physical properties of the two pesticides, such as Koc and water solubility [14,15]. Dinotefuran has better water solubility than imidacloprid, which may explain the higher plant absorption and higher groundwater contamination potential with C. brownei planting.…”