Degradation of Imidacloprid in Chrysanthemi Flos and Soil

Abstract

Degradation of imidacloprid in chrysanthemi flos and cultivated soil was studied. The half-lives of imidacloprid were 3.55-5.17 days (soil), 2.10-3.98 days (fresh buds and flowers), 22.14 days (dry flowers, 5°C) and 13.08 days (dry flower, 20°C), separately. The temperature can affect imidacloprid degradation in soil and dry chrysanthemum buds and flowers. Imidacloprid residues in chrysanthemum flowers were more stable during store stage than growing one. Few imidacloprid residues would be dissolved into chrysanthemum tea liquor when the residue in dry buds or dry flowers was below 0.8 mg/kg.

Reduction of Imidacloprid by Sponge Iron and Identification of its Degradation Products

“…The imidacloprid solution was then transferred in its entirety to a 50 mL cylindrical beaker and subjected to reduction using sponge iron (excess during degradation) in acidic conditions. Temperature has obvious effects on pesticide degradation (Ma et al, 2012;Wu et al, 2012), therefore, the degradation experiment was carried out in a cylindrical single-compartment where the reactor was externally immersed in water to keep the reaction at a constant temperature of 20 6 2 8C. This ensured the reduction degradation was performed at, approximately, ambient temperature.…”

Biodegradation of imidacloprid in sandy loam soil byBacillus aerophilus

“…Environmental Protection Agency placed imidacloprid in category I as having the highest leaching potential [7]. Degradation of imidacloprid in chrysanthemi flos and cultivated soil was also studied by Wu et al [8]. The half-lives of imidacloprid were 3.55-5.17 days in soil, 2.10-3.98 days in fresh buds and flowers, 22.14 days in dry flowers at 5°C and 13.08 days in dry flower at 20°C.…”

Isolation and Characterization of a Novel Imidacloprid-DegradingMycobacteriumsp. Strain MK6 from an Egyptian Soil

“…14 IMDA is characterized by variable persistence in soil, with a half-life up to 229 days in the field. 18 In contrast, Wu et al 19 found under laboratory conditions that the degradation of IMDA was rapid, with half-lives of 4−5 days. The persistence of IMDA in water increased with increasing application rates and pH values.…”