Evaluation of chlorpyrifos transferred from contaminated feed to duck commodities and dietary risks to Chinese consumers

A fast multi-residue analysis of twenty-four classes of pesticide in sesame (Sesamum indicum L.) and their migration into processed products

Sesame is widely used as a nutritional supplement or condiment because of its nutritious properties and palatable flavor. However, the extensive use of pesticides in sesame fields has paradoxically decreased the nutritional vantage. The current study used QuEChERS with a low-temperature freezing method to develop a multi-residue analytical approach to detect target analytes (pesticides) in sesame seed, sesame oil, sesame paste, and sesame meal. The migration ability of target pesticides during oil processing was investigated using HPLC-MS/MS and GC-MS: 35% of pesticides decreased, with processing factors (PFs) lower than 0.98, whereas 65% migrated from the seed to the oil during processing. The migration success of methoxyfenozide was the highest, while clothianidin and pymetrozine demonstrated a significantly lower rate of transfer. The results provide insight into the types of pesticides that should be used in farming practices of sesame to decrease the impact on human health.

Multiresidue determination of antibiotics in ready-to-eat duck eggs marketed through e-commerce stores in China and subsequent assessment of dietary risks to consumers

In this work, the occurrence of 34 common antibiotic (15 sulfonamides and 19 quinolones) residues were evaluated in 236 ready-to-eat duck eggs (salted and preserved duck eggs) marketed through e-commerce stores by ultra-performance liquid chromatography coupled to tandem mass spectrometry, and subsequent dietary risk assessments for Chinese consumers were conducted. Among violated positives in duck egg samples, 11 analytes were found including sulfamethazine, sulfaquinoxaline, sulfamethoxazole, sulfadiazine, sulfamonomethoxine, ciprofloxacin, enrofloxacin, ofloxacin, flumequine, sarafloxacin, and nalidixic acid. A higher number of antibiotics were detected in salted duck eggs (five sulfonamides and six quinolones) than in preserved duck eggs (one sulfonamide and two quinolones). The maximum contamination of sulfonamides and quniolones was 448.0 µg/kg (sulfaquinoxaline) and 563.7 µg/kg (enrofloxacin) in salted duck eggs, respectively. Dietary exposure was evaluated through the estimated daily intake (EDI) of risky antibiotics (sulfamethazine, ciprofloxacin, and enrofloxacin) and hazard quotients (HQs). The results showed that EDIs and HQs were in the range of 0.0004 to 0.0099 µg/kg bw/day and 0.0009 to 0.1594%, respectively. The risk was low since HQs obtained were less than 100%. However, a special attention should be paid to ready-to-eat duck egg products high percentile consumers with the prosperity of e-commerce market in China. PRACTICAL APPLICATION: The present analytical method could be used for multiresidue determination of antibiotics in ready-to-eat duck eggs, and dietary risk assessments of risky antibiotics provided a support for the work of regulatory bodies to conduct surveillance programs regarding food safety evaluation of ready-to-eat foods.

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

BACKGROUND

Triadimefon is a fungicide used in agriculture to control fungal diseases such as sclerotinia sclerotiorum.

RESULTS

In field trials, rape plants were sprayed with triadimefon at three different dosages during the flowering period. The degradation of triadimefon and the residue levels of its metabolite, triadimenol, in rapeseed obtained from harvesting, storage, and household oil processing were traced and evaluated. The pesticides were determined by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) at each processing step. Triadimefon degraded completely and only its metabolite, triadimenol, was detected in rapeseed after harvesting. The stability of triadimenol in rapeseed was studied at weekly storage intervals, from 0 to 7 weeks at ambient temperature (25 °C) and freezing temperature (-20 °C), respectively. Storage temperature had an important influence on the residue levels of triadimenol. The processing factor (PF) was defined as the ratio of pesticide residue levels in rapeseed to rapeseed oil levels during household oil processing. The average PF of triadimenol was about 0.96 for a hot pressing technique and 0.88 for a cold pressing technique.

CONCLUSION

Different storage conditions and food processing could reduce the pesticide level to a greater or lesser extent. However, it is not easy to eliminate or significantly weaken triadimenol once triadimefon has degraded completely. © 2018 Society of Chemical Industry.

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

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.

Transfer Assessment of Carbendazim Residues from Rape Flowers to Apicultural Products

Carbendazim is usually used to control the Sclerotinia sclerotiorum of rapes during the flowering period. This paper presents a study on transfer assessment of carbendazim residues from rape flowers to apicultural products. In the field trials, the rapes were sprayed with carbendazim on standard dosage. Bees produced apicultural products (bee pollen, honey, and royal jelly) from sprayed rapes. Apicultural products were collected on a regular basis. Carbendazim residues were extracted from bee pollen, honey, and royal jelly, respectively. HPLC/ESI-MS/MS method was developed and partially validated to identify and quantify carbendazim residues. The limits of quantification in pollen, honey, and royal jelly were 0.01 mg/kg. Mathematical curve fitting was carried out on the basis of transfer assessment of carbendazim residues from rape flowers to apicultural products. The respective carbendazim residues were 1.10 ± 0.03 mg/kg in pollen on 18th day, 0.032 ± 0.001 mg/kg in honey on 24th day, and 0.077 ± 0.002 mg/kg in royal jelly on 22nd day. Transfer assessment and mathematical curve fitting of carbendazim residues from rape flowers to apicultural products show carbendazim diminished over spraying time. The gap of carbendazim residues between pollen and honey is decreased with time. The carbendazim residues in pollen are 10 times higher than that of honey and jelly.