Residue levels, processing factors and risk assessment of pesticides in ginger from market to table.

Ginger is consumed as a spice and medicine globally. However, pesticide residues in ginger and their residue changes during processing remain poorly understood. Our results demonstrate that clothianidin, carbendazim and imidacloprid were the top detected pesticides in 152 ginger samples with detection rates of 17.11-27.63%, and these pesticides had higher average residues of 44.07-97.63 µg/kg. Although most samples contained low levels of pesticides, 66.45% of the samples were detected with pesticides, and 38.82% were contaminated with 2-5 pesticides. Peeling, washing, boiling and pickling removed different amounts of pesticides from ginger (processing factor range: 0.06-1.56, most <1). By contrast, pesticide residues were concentrated by stir-frying and drying (0.50-6.45, most >1). Pesticide residues were influenced by pesticide physico-chemical parameters involving molecular weight, melting point, degradation point and octanol-water partition coefficient by different ginger processing methods. Chronic and acute dietary risk assessments suggest that dietary exposure to pesticides from ginger consumption was within acceptable levels for the general population. This study sheds light on pesticide residues in ginger from market to processing and is of theoretical and practical value for ensuring ginger quality and safety.

Dissipation, accumulation, distribution and risk assessment of fungicides in greenhouse and open-field cowpeas.

Pesticide residues in cowpeas have raised worldwide concern. However, only a few studies have focused on pesticide accumulation and distribution in greenhouse and open-field cowpeas. Field trial results suggest that difenoconazole, dimethomorph, thifluzamide and pyraclostrobin dissipated faster in open fields (mean half-lives, 1.72-1.99 days) than in greenhouses (2.09-3.55 days); moreover, fungicide residues in greenhouse cowpeas were 0.84-8.19 times higher than those in the open-field cowpeas. All fungicides accumulated in the greenhouse and open-field cowpeas after repeated spraying. Fungicide residues in old cowpeas were higher than those in tender cowpeas, and residues in the upper halves of cowpea pods were higher than those in the lower halves. In addition, cowpeas distributed in the lower halves of the plants had higher fungicide residues. Our findings suggest that greenhouse cultivation contributed to the pesticide residues in cowpeas after repeated spraying, although the levels of dietary health risks remained acceptable under both cultivation scenarios.

Dissipation, Metabolism, Accumulation, Processing and Risk Assessment of Fluopyram and Trifloxystrobin in Cucumbers and Cowpeas from Cultivation to Consumption.

Fluopyram and trifloxystrobin are widely used for controlling various plant diseases in cucumbers and cowpeas. However, data on residue behaviors in plant cultivation and food processing are currently lacking. Our results showed that cowpeas had higher fluopyram and trifloxystrobin residues (16.48-247.65 µg/kg) than cucumbers (877.37-3576.15 µg/kg). Moreover, fluopyram and trifloxystrobin dissipated faster in cucumbers (half-life range, 2.60-10.66 d) than in cowpeas (10.83-22.36 d). Fluopyram and trifloxystrobin were the main compounds found in field samples, and their metabolites, fluopyram benzamide and trifloxystrobin acid, fluctuated at low residue levels (≤76.17 µg/kg). Repeated spraying resulted in the accumulation of fluopyram, trifloxystrobin, fluopyram benzamide and trifloxystrobin acid in cucumbers and cowpeas. Peeling, washing, stir-frying, boiling and pickling were able to partially or substantially remove fluopyram and trifloxystrobin residues from raw cucumbers and cowpeas (processing factor range, 0.12-0.97); on the contrary, trifloxystrobin acid residues appeared to be concentrated in pickled cucumbers and cowpeas (processing factor range, 1.35-5.41). Chronic and acute risk assessments suggest that the levels of fluopyram and trifloxystrobin in cucumbers and cowpeas were within a safe range based on the field residue data of the present study. The potential hazards of fluopyram and trifloxystrobin should be continuously assessed for their high residue concentrations and potential accumulation effects.

Dissipation, metabolism, accumulation, processing and risk assessment of fluxapyroxad in cucumber and cowpea vegetables from field to table.

Understanding the residue fate of fluxapyroxad is critical for food safety and human health. The present study profiled the dissipation, metabolism, accumulation, removal and risk assessment of fluxapyroxad in cucumbers and cowpeas from field to table. Greenhouse-field trials suggested that fluxapyroxad dissipated faster in cucumbers than in cowpeas, and M700F008 was the only detected metabolite at

Risk assessment of multiple-mycotoxin exposure for consumers of chestnuts in Shandong Province markets in China.

In this study, 321 chestnut samples from Shandong Province in China were analysed for the presence of mycotoxins. We screened for 14 mycotoxins including aflatoxins (AFs: AFB1, AFB2, AFG1, AFG2), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), T-2 toxin (T-2), zearalenone (ZEA), ochratoxin A (OTA), fumonisins (FB1, FB2, FB3), and penicillic acid (PeA). Mycotoxins were detected in 56.4% of the samples, and 11 of these mycotoxins were found. Thirty samples from the Shandong Province markets were deemed positive for AFs (9.3%) and had an AFB1 level of >2 µg/kg or a sum of AFB1, AFB2, AFG1, and AFG2 that was >4 µg/kg, which exceed the maximum tolerable level of the European regulations standards (EC/188/2006). The contamination level for total mycotoxins found in chestnuts was in the range of 0.6-2,791.0 µg/kg. The estimated daily intake (EDI) values for each individual mycotoxin and for all of the mycotoxins collectively were calculated by both a deterministic approach and a probabilistic approach. For risk characterisation, dietary exposure to DON, ZEA, FBs, and OTA through consumption of chestnuts, analysed according to both approaches, showed no health risk to Chinese adolescents and adults from exposure to either individual mycotoxins or in combination, but more concern should be paid to the AFs for adolescents and adults at a high consumption level. This is believed to be the first work performing risk assessment of multiple mycotoxins specifically for adolescents, including the recently isolated FBs and PeA, which have recently emerged as mycotoxins of concern, in chestnuts of Shandong Province in China.

Residues and dissipation kinetics of carbendazim and diethofencarb in tomato (Lycopersicon esculentum Mill.) and intake risk assessment.

Dissipation behaviors and residues of carbendazim and diethofencarb in combination in tomato were investigated. The half-lives were 2.1-3.4 days for carbendazim, and 1.8-3.2 days for diethofencarb at a dose of 1.5 times of the recommended dosage. The residues of carbendazim and diethofencarb were below the maximum residue limits (MRLs) in China one day after application of the combination. The ultimate residues were significantly lower than the maximum permissible intake (MPI) in China at the recommended high dose for both child and adult. The values of the maximum dietary exposure for carbendazim and diethofencarb were 0.26 and 0.27 mg per person per day, respectively. The theoretical maximum daily intake (TMDI) values for carbendazim and diethofencarb were 1.5 and 0.5 mg/day, respectively. The dietary exposure was lower than the MPI, which indicates the harvested tomato samples under the experimental conditions (open field) are safe for human consumption at the recommended high dosage of the wettable powder.

Risk assessment of pesticide residues in dietary intake of celery in China.

OBJECTIVE: Residue risk assessment of pesticides in celery was conducted to provide a scientific basis for agricultural regulation policies and working procedures. METHODS: Three hundred samples from eight main growing regions in China were collected and pesticide residue analyses were performed using GC-MS/MS and LC-MS/MS methods. Both chronic and acute intake risk of pesticides were assessed. Furthermore, intake risk of each detected pesticide was ranked according to a predefined ranking matrix. RESULTS: (1) Out of these 300 samples, 175 were revealed to contain one or more pesticide residues. Twenty-five pesticides were identified in total, out of which, carbofuran was found to exceed the maximum residue limit. (2) Chronic and acute intake risks were evaluated and lie in between 0 and 1.80 and between 0.05 and 28.0 for these twenty-five pesticides, respectively. (3) Intake risk of individual pesticide was ranked; five pesticides, including avermectin, triazophos, chlorpyrifos, dimethoate oxygen, and carbofuran posed the highest risks. CONCLUSION: Pesticide residues were detected in more than 58% celery samples in our study. Most pesticides have a residue level lower than their maximum residue limit and pose low chronic and acute dietary intake risk. However, usage of some pesticides like carbofuran should be closely monitored and regulated in the future.