In vivo metabolic fate of [¹⁴C]‐acetamiprid in six biological compartments of the honeybee, Apis mellifera L

Abstract

The in vivo metabolism of acetamiprid was studied in the honeybee, Apis mellifera L. The distribution of acetamiprid and its metabolites was monitored over a 72-h period in six biological compartments: head, thorax, abdomen, haemolymph, midgut and rectum. Honeybees were treated orally with 100 microg [14C]-acetamiprid kg(-1) bee, a dose which is about 1500 times lower than the median lethal dose. After 72 h, only 40% of the total radioactivity was eliminated, suggesting that acetamiprid and its metabolites tended to persist in the honeybee. Acetamiprid was rapidly distributed in all compartments and metabolized. Just after administration, radioactivity was mainly localized in the abdomen and subsequently in the rectum. After 72 h, the maximum amount of radioactivity (about 20% of the ingested dose) was detected again in the abdomen, whereas the lowest level of total radioactivity was detected in the haemolymph. Radioactivity in the head did not exceed 7.6% of total ingested radioactivity. More than 50% of acetamiprid was metabolised in less than 30 min, indicating a very short half-life for the compound. During the first hours, acetamiprid was mainly detected in nicotinic acetylcholine receptor-rich tissues: abdomen, thorax and head. Of the seven metabolites detected, the major ones were 6-choronicotinic acid and an unknown metabolite called U1, which was present mainly in the rectum, the thorax and the head. Our results indicate that the low toxicity of acetamiprid may reflect its rapid metabolism.

N-demethylation of neonicotinoid insecticide acetamiprid by bacterium Stenotrophomonas maltophilia CGMCC 1.1788

“…However the substrate AAP was continuously reduced. In honeybee and plant, the further degradation of IM 2-1 yields the end products namely, IC-O (6-chloro-nicotinic acid) (Brunet et al 2005). However beside the product IM 2-1, no other metabolite in transformation broth was observed under UV wavelength by HPLC analysis in this study.…”

“…Study on the metabolism of AAP by plant, rat and honeybee showed that, besides producing metabolites such as IM 1-2, IM 1-4, IM 1-5 and IC-0, the N-demthylation of AAP to yield IM 2-1 was the main pathway (Brunet et al 2005). However, metabolic products of AAP in soils under aerobic conditions were IM 1-4, IM 1-5 and IC-0, while the metabolic products of AAP in an aerobic sediment-water system were IM 1-2, IM 1-4 and IC-0.…”

An assessment of honeybee colony matrices, Apis mellifera (Hymenoptera: Apidae) to monitor pesticide presence in continental France

“…Imidacloprid has an elimination half-life in honeybees of 4.5 h [32] resulting in two main metabolites, 6-chloronicotinic acid and the urea derivative. The metabolic pathway for other neonicotinoid insecticides such as acetamiprid also ends in 6-chloronicotinic acid [34]. This suggests that 6-chloronicotinic acid residues might not have originated only from exposure to imidacloprid but also from other neonicotinoid insecticides such as acetamiprid.…”

Studies on <i>Aphis gossypii</i> cytochrome P450s CYP6CY22 and CYP6CY13 using an <i>in vitro</i> system

“…3A-C). [37][38][39] Hydroxylation and N-dealkylation are likely the key reactions catalyzed by A. gossypii CYP6CY22 and CYP6CY13, respectively.…”