Different dissipation potential and dietary risk assessment of tristyrylphenol ethoxylates in cowpea ecosystem in China.

Tristyrylphenol ethoxylates (TSPEOn) are widely used as inert ingredients in pesticide formulations in the world. However, the information on the dissipation behavior of different homologs TSPEOn in agro-products is lacking. To investigate the dissipation behavior of TSPEOn, a cowpea field experiment treated with TSPEOn at different doses was carried out in Guangdong province, China. Different 24 TSPEO homologs were all detected in cowpea from the field terminal residue experiments, and the total concentrations of TSPEO homologs in cowpea were 40.0-1,374 µg/kg. The dissipation half-lives of 24 TSPEO homologs in soil were 1.51-2.35 times longer than those in cowpea. The long-chain homologs TSPEOn were dissipated faster than the short-chain homologs TSPEOn, suggesting a homolog-specific degradation of the TSPEOn in the cowpea ecosystem. The characteristic bimodal profiles of TSPEOn (n = 6-29) differing from that of the commercial TSPEOn were observed in the cowpea terminal residues experiment, indicating that the long-chain TSPEOn would degrade to short-chain TSPEOn in cowpea and soil. The acute and chronic dietary exposure risks of ΣTSPEOn in cowpea are within acceptable margins for human consumption across different ages and genders. But the health risks to children should be noticed in future.

Residue and Risk Assessment of Fluopyram in Carrot Tissues.

This study describes the variation in residue behavior of fluopyram in soil, carrot root, and carrot leaf samples after the application of fluopyram (41.7% suspension, Bayer) by foliar spray or root irrigation at the standard of 250.00 g active ingredient per hectare (a.i./ha) and double-dose treatment (500.00 g a.i./ha). Fluopyram and its metabolite fluopyram-benzamide were extracted and cleaned up using the QuEChERS method and subsequently quantified with LC-QQQ-MS/MS. The LOD and LOQ of the developed method were in the range of 0.05-2.65 ug/kg and 0.16-8.82 ug/kg, respectively. After root irrigation, the final residues detected in edible parts were 0.60 and 1.80 mg/kg, respectively, when 250.00 and 500.00 g a.i./ha were applied, which is much higher than the maximum residue limit in China (0.40 mg/kg). In contrast, after spray application, most of the fluopyram dissipated from the surface of carrot leaves, and the final residues in carrot roots were both only 0.05 mg/kg. Dietary risk assessments revealed a 23-40% risk quotient for the root irrigation method, which was higher than that for the foliar spray method (8-14%). This is the first report comparing the residue behavior of fluopyram applied by root irrigation and foliar spray. This study demonstrates the difference in risk associated with the two application methods and can serve as a reference for the safe application of fluopyram.

Fraud vulnerability quantitative assessment of Wuchang rice industrial chain in China based on AHP-EWM and ANN methods.

Vulnerability assessment has been used in the food fraud mitigation based on the subjective judgement of industry participants and simple calculation. To have a more objective result, an improved vulnerability quantitative assessment method was proposed. The overall fraud vulnerability was described by the vulnerability of fraud factors and the health and economic impact of fraud incidents. The fraud factors were related to opportunity, motivation and control measure. Analytic hierarchy process combined with entropy weighting method (AHP-EWM) and artificial neural networking (ANN) to improve judgment accuracy. In the application in Wuchang rice industrial chain, 51 fraud factors were used in the assessment and 10 experts, 36 farmers, 15 suppliers and 15 supervisors were interviewed. Results showed that Wuchang rice industrial chain was highly vulnerable to fraud. The opportunity for fraud was high, the motivation to commit it was moderate, and controls to prevent it needed reinforcing. Fraud vulnerability differed between farmers and suppliers. To reduce the fraud vulnerability, improved regulations and policies and stiffer penalties were strongly recommended.

Dietary exposure and risk assessment of cyanide via cassava consumption in Chinese population.

The intake of cassava would probably induce adverse health effects since there are toxic cyanide in cassava. However, the risk assessment of cassava consumption has not been reported in China. Therefore, this paper aimed to evaluate the dietary risks of cassava cyanide and proposed a maximum residue limit (MRL) for cyanogenic glycosides (CNGs) in cassava. The retention rate of CNGs and CN- were 61% and 11% after boiling, respectively. The acute dietary exposure of CN- and CNGs were 0.6-fold and 1.7-fold of acute risk reference dose, respectively. There was no chronic health risk across all populations concerning cassava consumption. The MRL of CNGs was proposed as 200 mg/kg in cassava. Risk assessment of cyanide for foods rich in CNGs was suggested to be based on CNGs quantification rather than that of CN-.

Residue behaviors and risk assessment of flonicamid and its metabolites in the cabbage field ecosystem.

Flonicamid, a novel selective systemic pesticide, can effectively control a broad range of insect pests. However, the dissipation behaviors and the terminal residues of flonicamid and its metabolites in some crops and soils remain unclear. Herein, an easy, sensitive and reliable method using a modified QuEChERS extraction coupled with LC-MS/MS for the simultaneous analysis of flonicamid and its metabolites in cabbage and soil was developed. Based on this method, the dissipation behaviors of flonicamid and its metabolites as well as their persistence in cabbage and soil during harvest were investigated. Flonicamid degraded rapidly, and the half-lives of flonicamid only and total residues (the sum of flonicamid and its metabolites) were 1.49-4.59 and 1.97-4.99 days in cabbage, and 2.12-7.97 and 2.04-7.62 days in soil, respectively. When 50% flonicamid WG was sprayed once or twice at the recommended dose and 1.5-fold the recommended dose, the highest residues of total flonicamid in cabbage and soil from different pre-harvest intervals (3, 7 and 14 days) were 0.070 and 0.054 mg kg-1, respectively. The risk quotient (RQ) of flonicamid based on the consumption data from China was below 16.84%, indicating that the use of flonicamid is non-hazardous to humans. These results could not only guide the safe and responsible use of flonicamid in agriculture but also help the Chinese government establish the maximum residue level (MRL) for flonicamid in cabbage.

Risk assessment of dietary exposure to phytosterol oxidation products from baked food in China.

Phytosterols are nutritional phytochemicals that may undergo oxidation and be transformed into phytosterol oxidation products (POPs), thus inducing pathological and toxic effects. This work investigated four main phytosterols and 28 POPs in 104 kinds of commercial baked food by using GC-MS. The dietary exposure and hazard index values (HI) associated with POPs from baked food consumption in China were estimated by using Monte Carlo simulation. Concentrations of the total phytosterols were between 3.39 and 209.80 µg/g. The total concentrations of POPs, including 5α,6α/5ß,6ß-epoxysterols, 7-ketosterol, 7α/7ß-hydroxysterols, 6-hydroxysterols, and triols, ranged from 0.37 to 27.81 µg/g. The median dietary exposure of POP contents in baked food for four age groups in China were 10.91 (children), 6.20 (adolescents), 3.63 (adults), and 3.40 (seniors) mg/(kg×day). Risk assessment of median HI with respect to POPs indicated no risk (HI <1) for people in adolescents, adults, and seniors in the country area of China, while a risk (1 < HI < 10) would refer to the baked food consumption of people in urban area and children in country area of China. Sensitivity and uncertainty analysis showed that the most significant variables for each age group in China were POP concentration, body weight, and ingestion rate.

Monitoring, exposure and risk assessment of sulfur dioxide residues in fresh or dried fruits and vegetables in China.

Sulfur dioxide residues in 20 kinds of products collected from 23 provinces of China (Jilin, Beijing, Shanxi, Shandong, Henan, Hebei, Jiangsu, Anhui, Shanghai, Zhejiang, Fujian, Guangdong, Guangxi, Yunnan, Guizhou, Hunan, Hubei, Chongqing, Sichuan, Gansu, Neimenggu, Xinjiang and Hainan) were analysed, and a health risk assessment was performed. The detection rates of sulfur dioxide residues in fresh vegetables, fresh fruits, dried vegetables and dried fruits were 11.1-95.9%, 12.6-92.3%, 70.3-80.0% and 26.0-100.0%, respectively; the mean concentrations of residues were 2.7-120.8, 3.8-35.7, 26.9-99.1 and 12.0-1120.4 mg kg-1, respectively. The results indicated that fresh vegetables and dried products are critical products; the daily intakes (EDIs) for children were higher than others; the hazard indexes (HI) for four groups were 0.019-0.033, 0.001-0.005, 0.007-0.016 and 0.002-0.005 at P50, respectively. But the HI was more than 1 at P99 by intake dried fruits and vegetables. Although the risk for consumers was acceptable on the whole, children were the most vulnerable group. Uncertainty and sensitivity analyses indicated that the level of sulfur dioxide residues was the most influential variable in this model. Thus, continuous monitoring and stricter regulation of sulfites using are recommended in China.