Transfer and Metabolism of Triadimefon Residues from Rape Flowers to Apicultural Products

Abstract

This paper presents a study on the transfer and metabolism of triadimefon residues from rape flowers to apicultural products. In the field trials, honeybee colonies were placed in four rape greenhouses treated with triadimefon on standard dosage. Apicultural products (pollen, honey, and royal jelly) were collected on a regular basis. Sample preparation and extraction procedure were established. HPLC/ESI-MS/MS method was validated. The respective residues of triadimefon and metabolite triadimenol were 0.03 ± 0.002 mg/kg and 0.13 ± 0.02 mg/kg in pollen on the 18th day, and both had reached the limits of detection in honey on the 24th day, while they were 0.004 ± 0.0005 mg/kg and 0.010 ± 0.0002 mg/kg in royal jelly on the 22nd day. Mathematical curve fitting studies were further investigated. On the basis of recommended dosage, the degradation half-lives of triadimefon in pollen, honey, and royal jelly were about 0.7, 12.5, and 19.5 days, respectively. Transfer of triadimefon residues from rape flowers to apicultural products diminished over spraying time. The residues of triadimefon and metabolite triadimenol in pollen were about 10 times higher than those in honey and jelly. Time to attain the maximum permissible limit of pollen in the European Union was 14.9 days, predicted from the index function.

Occurrence of pesticide residues in honey from apiaries with incidents of honeybee poisoning in East China and a corresponding risk assessment for honeybees and Chinese consumers

“…Thus, the major presence of carbendazim with a 99.0% incidence in this study was not surprising. In combination with previously published data, our study also found that carbendazim was commonly present in various honeybee products in different countries (Amulen et al., 2017; David et al., 2016; Li et al., 2017). At field levels, Carbendazim was not an acutely lethal pesticide; however, field‐realistic concentrations of carbendazim (45.1 µg/kg) might harm P450‐mediated detoxification and the immune system of honeybees (Cang et al., 2012; Shi et al., 2018).…”

Degradation of triadimefon and residue levels of metabolite triadimenol: tracing rapeseed from harvesting and storage to household oil processing

“…Extraction and purification procedures followed the buffered QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method . The procedures were almost the same as those used in our earlier studies . A representative 6 g portion of thoroughly homogenized rapeseed sample was weighed in a 50 mL centrifuge tube, followed by the addition of 9 mL of purified water and 15 mL acetonitrile.…”

“…[26][27][28] The procedures were almost the same as those used in our earlier studies. 12 A representative 6 g portion of thoroughly homogenized rapeseed sample was weighed in a 50 mL centrifuge tube, followed by the addition of 9 mL of purified water and 15 mL acetonitrile. Then the tube was shaken vigorously for 1 min using a vortex mixer.…”

“…In food‐safety issues, it is necessary to trace the whole course from harvesting and storage to processing, to ensure healthy and safe catering for consumers. Transfer assessment and mathematical curve fitting of pesticide residues, from rapeseed to apicultural products, have shown that pesticide residues diminish over spraying time . The optimum harvest time for agricultural products is a certain number of days after spraying pesticide.…”

“…Transfer assessment and mathematical curve fitting of pesticide residues, from rapeseed to apicultural products, have shown that pesticide residues diminish over spraying time. 12,13 The optimum harvest time for agricultural products is a certain number of days after spraying pesticide. Storage conditions are related to residue levels of post-harvest agricultural products.…”