Dietary Intake Risk Assessment Research Articles

Residue and dietary intake risk assessment of lufenuron and chlorfenapyr and its corresponding metabolite in cabbage under field conditions.

A simple, low-cost, and highly sensitive method using a modified QuECHERS procedure based on a liquid chromatography-tandem mass spectrometer (LC-MS/MS) was established to simultaneously quantify lufenuron and chlorfenapyr and the corresponding metabolite tralopyril in cabbage for the first time. On the basis of this method, terminal residue and dietary risk of lufenuron and chlorfenapyr in cabbage were investigated. The recoveries of lufenuron, chlorfenapyr, and tralopyril ranged from 88 to 110%, with relative standard deviation of less than 12.4%. The field trial results showed that at the pre-harvest interval (PHI) of 21 days, the terminal residues of lufenuron, chlorfenapyr, and tralopyril in the supervised trials were not higher than 0.02 mg/kg, and the highest detected residue levels of lufenuron, chlorfenapyr, and tralopyril were 0.047, 0.055, and <0.02 mg·kg-1 at 14-day pre-harvest respectively, which were lower than the maximum residue limits (MRLs) for cabbage established in China. For the dietary risk assessment, the national estimated daily intakes (NEDIs) as proportion of acceptable daily intakes (ADIs) were 80.4% and 29.9% for chlorfenapyr and lufenuron respectively indicating an acceptable dietary risk to Chinese population.

Multiresidue analysis and dietary intake risk assessment of 29 pesticides in banana from five provinces of southern China

The present study utilized a combined quick, easy, cheap, effective, rugged, safe (QuEChERS) method with ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) to detect and quantify pesticide residues in both whole banana fruit and pulp samples collected from five provinces in southern China between June 2018 and December 2021. The analysis identified the occurrence of 29 widely used insecticides, fungicides, and herbicides on bananas, including organophosphates, organochlorines, pyrethroids, triazoles, etc. The limits of quantification for the pesticides analyzed in the banana matrix ranged from 1.0 to 5.0 μg/kg. Among the 501 samples collected, the detection rates of pesticides in whole fruit and pulp samples were 65.1 % and 40.9 %, respectively. Specifically, 20 kinds of pesticides were detected in whole fruit samples, while 16 were detected in pulp samples. Furthermore, imidacloprid was detected across various regions and years. The evaluation of risk of hazard quotient (HQ) to the identified pesticides in whole fruit and pulp samples revealed values ranging from 0.0016-0.0313 and 0.0002–0.0131, respectively. Overall, the results suggest that the detected pesticide residues in bananas are unlikely to pose an unacceptable health risk to consumers of different age groups in China.

The Dissipation Kinetics, Residue Level and Dietary Risk of Kresoxim-Methyl in Rosa roxburghii and Soil Based on the QuEChERS Method Coupled with LC-MS/MS.

This study aimed to investigate the dissipation, residues and dietary assessment of kresoxim-methyl in the application of Rosa Roxburghii and soil field using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results show that kresoxim-methyl in R. roxburghii samples was extracted by acetonitrile and purified by ethyl enediamine-N-propylsilane (PSA), while kresoxim-methyl in soil samples was extracted by acetonitrile and purified by octadecylsilyl solid phase dispersant (C18). 0.1% formic acid (v/v)-water-methanol solution was used as the mobile phase, LC-MS/MS exhibited a good linearity in the range of 0.001-10mgL-1. The recoveries of R. roxburghii and soil matrix were 82.48%-102.55%, and the relative standard deviation (RSD) were 1.13%-4.21%. The limit of detection (LOD) and quantification (LOQ) of kresoxim-methyl in R. roxburghii and soil samples was 0.50 and 0.60µgkg-1, respectively. The dissipation dynamics of kresoxim-methyl in R. roxburghii and soil followed the first-order kinetics, with the half-life of 4.28 and 4.41days, respectively. The terminal residual amount of kresoxim-methyl in R. roxburghii and soil samples was 0.003-1.764 and 0.007-2.091mgkg-1, respectively. The dietary intake risk assessment indicates that a risk quotient (RQ) for kresoxim-methyl based on the national estimated daily intake (NEDI) of 0.1995mg was 0.79%, suggesting that the use of kresoxim-methyl on R. roxburghii at recommended dosage was safe to consumers. This study provides the theoretical basis for guiding the rational use of kresoxim-methyl in the production of R. roxburghii.

Optimization of a QuEChERS–LC–MS/MS method for 51 pesticide residues followed by determination of the residue levels and dietary intake risk assessment in foodstuffs

A modified QuEChERS purification–liquid chromatography-tandem mass spectrometry method has been developed to determine 51 pesticide residues with newly established maximum residue limits (MRLs) in foodstuffs. Samples were extracted with acetonitrile under citrate-buffered conditions and purified using a modified QuEChERS method employing hydroxylated MWCNTs, SAX, and C18. The limits of quantification ranged from 0.2 to 9.8 µg/kg. Recoveries in ten different foodstuffs ranged from 70.2% to 117.9%, with relative standard deviations between 2.3% and 19.9% at three spiking levels. This method was applied to analyze 352 market samples, detecting 14 pesticides in 97 samples. Notably, Afidopyropen, cyantraniliprole, and fluxapyroxad residues in vegetables exhibited a consistent pattern of higher levels in the spring and winter and lower levels in the summer and autumn. Moreover, the risk assessments for acute and chronic dietary exposure to the 14 detected pesticides indicated that the %ADI and %ARfD were well below 100%.

Simultaneous determination and dietary intake risk assessment of 60 herbicide residues in aquatic products

A sensitive and rugged analytical method was first established to simultaneously determine 60 herbicides in aquatic products with gas chromatography–tandem mass spectroscopy (GC–MS/MS). After extraction with acetonitrile (MeCN), NaCl and anhydrous Na2SO4 were added, concentrated supernatants were directly passed through the Carb/NH2 solid phase extraction column. Then, the cartridge was rinsed with elution solution (MeCN/toluene, 3:1, v/v), followed by GC–MS/MS analysis with multiple reaction monitoring. An excellent linearity (1.0–100.0 μg/L) with R2 value of ≥0.9991 was obtained, and the limits of quantification were 0.018–3.852 μg/kg. Satisfactory recoveries (70.8 %–117.6 %) with RSDs below 11.0 % of herbicide residues were obtained at spiked levels of 0.010–0.050 mg/kg. Furthermore, herbicide residues in actual aquatic products were analyzed, and the acute/chronic risk assessment of dietary exposure was carried out. The wide use of herbicides for controlling weed and removing moss and harmful algae may obviously increase the risk of contamination of the aquaculture environment and fishery products. Therefore, considerable attention and more research are necessary to monitor residue levels for herbicides in aquatic products and ensure the quality of marine products and consumer safety.

Residual Behavior and Dietary Risk Assessment of Chlorfenapyr and Its Metabolites in Radish

Chlorfenapyr, as a highly effective and low-toxicity insect growth regulation inhibitor, has been used to control cross-cruciferous vegetable pests. However, the pesticide residue caused by its application threatens human health. In this paper, the residue digestion and final residue of chlorfenapyr in radish were studied in a field experiment. The results of the dynamic digestion test showed that the half-life of chlorfenapyr in radish leaves ranged from 6.0 to 6.4 days, and the digestion rate was fast. The median residual values of chlorfenapyr in radish and radish leaves at 14 days after treatment were 0.12 and 3.92 mg/kg, respectively. The results of the dietary intake risk assessment showed that the national estimated daily intake (NEDI) of chlorfenapyr in various populations in China were 0.373 and 5.66 µg/(kg bw·d), respectively. The risk entropy (RQ) was 0.012 and 0.147, respectively, indicating that the chronic dietary intake risk of chlorfenapyr in radish was low. The results of this study provided data support and a theoretical basis for guiding the scientific use of chlorfenapyr in radish production and evaluating the dietary risk of chlorfenapyr in vegetables.

Residual levels and dietary intake risk assessment of 11 pesticides in apricots from different ecological planting regions in China

The frequent and massive use of pesticides has led to pesticide residues in apricot, threatening food safety and human health. A reliable and simple modified QuEChERS method with ultra-performance liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of 11 pesticides in apricot. Method validation indicated that satisfied linearity (R2 ≥ 0.9959), accuracy (recoveries of 72–119%), sensitivity (limits of detection, 0.03–0.30 μg/kg; limits of quantification, 0.13–1.00 μg/kg), and precision (relative standard deviations ≤ 11.9%), and matrix effects were 0.89–1.13. Apricot samples from different ecological regions in China were collected and tested using the proposed methods. Monitoring results were used to assess the dietary intake risk of Chinese populations of different ages and genders. Dietary risk assessment revealed that the risk quotients were 0.003–1.184% for different gender and age groups in China, indicating none unacceptable public health risk for general population. This work was thus significant in developing a simpler, more efficient and economical analysis method and food safety risks of the 11 pesticides on apricot and facilitated the establishment of maximum residue limits.

Dissipation, Residue and Dietary Intake Risk Assessment of Penthiopyrad in Eggplants and Its Removal Using Various Household Processing Techniques.

A field trial was conducted to illustrate the dissipation and residue and assess the dietary intake risk of penthiopyrad in eggplants, and the distribution was further estimated after different household processing methods. Penthiopyrad dissipated quickly in eggplants, with half-lives of 1.85-2.56 days. The final residue data indicated that following the recommended spraying method, penthiopyrad would not threaten human health. Risk quotient results (&lt;&lt;100%) also demonstrated that the dietary intake risk of penthiopyrad in eggplants for Chinese consumers could be negligible. Washing, peeling and thermal treatments had significant removal effects on penthiopyrad from eggplants (0 &lt; processing factor &lt; 0.60). The characterization of the dissipation and distribution of penthiopyrad in field and processed eggplant samples could provide a more realistic reference for risk assessment of processed products, as well as some information for humans who may be exposed to penthiopyrad.

Effect of bifenthrin application at different maturity stages on its dissipation and residues in kumquat (Citrus japonica) and dietary intake risk assessment.

Bifenthrin is a pyrethroid pesticide widely used on kumquats, but the residues in the peel and pulp after bifenthrin application at different maturity stages of kumquats have not been evaluated. This study developed a simple and rapid high-performance liquid chromatography (HPLC) method for the quantitative analysis of bifenthrin residues in whole fruit, kumquat peel, kumquat pulp, and soil. The results showed that regardless of whether bifenthrin was applied one or three times during the near-mature period, the half-lives of the fruit peel and fruit pulp were longer than those in the immature period. Kumquat fruit residues decreased with time at both maturity levels. The residues of bifenthrin in near-mature fruit exceeded the MRL in Guangxi and Fujian 14days after the three applications of bifenthrin, suggesting that this issue should be focused on in kumquat production and supervision. However, for bifenthrin application in either the near-mature or the immature fruit period, the calculated risks for chronic dietary intake of kumquat were well below 100%. The data demonstrate that the chronic dietary intake risk of bifenthrin through kumquat consumption is low and within acceptable limits. These results provide a reference and risk assessment data for the safe and rational use of bifenthrin insecticides.

Residue analysis, dissipation patterns of chlorfenapyr, diafenthiuron and their corresponding metabolites in tea trees, and dietary intake risk assessment.

Recently, chlorfenapyr and diafenthiuron have been widely used to prevent and control diseases and pests in tea production. However, rare studies have investigated the dissipation patterns of chlorfenapyr, diafenthiuron and their metabolites simultaneously in tea matrices. Here, we established an analytical method to investigate the degradation patterns of five target compounds in tea shoots and made tea samples. Moreover, the dietary intake risk assessment of chlorfenapyr-diafenthiuron mixture among Chinese populations was evaluated based on the supervised field experiment. The mean recoveries of the primary analytes at five spiking levels were between 95.6% and 112.6% in tea shoots and made tea, respectively, and the values of RSD (relative standard deviation) were lower than 9.7% for all the target analytes. The field trial results showed that the half-lives of chlorfenapyr and diafenthiuron based on the residue definition were 10.0-12.4 days and 4.3-5.9 days, respectively, in tea shoots. For the dietary intake risk assessment, the risk quotient (RQ) values in made tea ranged from 30.4% to 73.9% at the pre-harvest interval of 14 days, which were significantly less than 100%. The accuracy and precision of the developed method were satisfied by the measurement requirements according to the validation results. The dynamic dissipation experiments suggested that diafenthiuron was much easier to dissipate than chlorfenapyr. Moreover, the existence of tralopyril made the half-life of chlorfenapyr significantly increase, indicating that practical application of chlorfenapyr should take careful consideration of its metabolite. Finally, the potential chronic dietary risks of the chlorfenapyr-diafenthiuron mixture to human communities were within the acceptable range. © 2022 Society of Chemical Industry.

Determination and dietary intake risk assessment of 35 pesticide residues in cowpea (Vigna unguiculata [L.] Walp) from Hainan province, China

The presence of pesticide residues in cowpea raises serious health concerns. In this study, a novel, sensitive, high-performance method was developed to simultaneously analyze the residues of 35 pesticides in cowpea samples from growing areas in the Hainan province of China, from November 2018 to June 2021. The method employs modified QuEChERS sample pretreatment coupled with gas chromatography-tandem mass spectrometry. The limits of quantification of the 35 pesticides in the cowpea matrix ranged from 1.0 to 8.0 μg/kg. Twenty-seven of the 35 pesticides were detected, twelve of which are banned for use on legumes in China. Residues for ten pesticides in 17.1% of the samples exceeded their MRLs, with the highest exceedance of 380% observed in difenoconazole. Moreover, 80.8% of the samples contained one or more pesticide residues, with the most frequently detected pesticide being chlorfenapyr with a detection rate of 46.3%. In addition, the pesticide triazophos was detected through different years and regions. Notably, the chronic dietary exposure risk (%ADI) of the detected pesticides, evaluated from the national estimated acceptable daily intake, was lower than 100% in Chinese people of different age groups.

Rapid determination and dietary intake risk assessment of 249 pesticide residues in Panax notoginseng

UPLC-MS/MS and GC-MS/MS were used to establish a method to simultaneously determine various pesticide residues in Panax notoginseng. Results showed that the limits of detection of 249 pesticides were all 5–10 μg/kg. The detection rate of pesticides in 121 P. notoginseng samples was 93.39%, and 19 pesticides were detected. According to the US Code of Federal Regulations, the Chinese Pharmacopoeia recommended algorithm, and the Japanese “positive list system”, the pass rates of pesticide residues were 100%, 99.17%, and 89.26%, respectively. The chronic risk quotient (ADI%) and acute risk quotient (ARfD%) of P. notoginseng were 0.00–0.12% and 0.00–0.15%, respectively. In summary, the detection method established in this study can be used for routine analysis of various P. notoginseng pesticide residues. The pesticide residues in the main root samples of P. notoginseng were at a safe level and unlikely pose health risks to consumers.

Residue, dissipation and dietary intake risk assessment of tolfenpyrad in four leafy green vegetables under greenhouse conditions.

A novel and accurate analytical method for the determination of tolfenpyrad in four leafy green vegetables, Brassica bara L., Spinacia oleracea L., Lactuca sativa L. and Brassica chinensis L., was developed and applied to investigate the residue distribution and dietary risk under greenhouse conditions. The established approach was determined to be adequate, with recoveries of 79.2%-92.9% and relative standard deviations<8%. Tolfenpyrad dissipated relatively rapidly in four leafy green vegetables. Terminal residues of tolfenpyrad were below 0.5mg/kg (maximum residue limit for Brassica bara L. set by China) in leafy green vegetables collected 28 d after the last application. Due to risk quotient values<100%, the residue levels of tolfenpyrad in leafy green vegetables collected 21days after the last application were deemed safe for consumers. The results provide field data for the reasonable use and dietary risk assessment of tolfenpyrad in leafy green vegetables.

Dissipation and residue of tebuconazole in banana (Musa nana L.) and dietary intake risk assessment for various populations

ABSTRACT In order to evaluate the safety of tebuconazole as a fungicide in bananas, after a simple and rapid pre-treatment, the residues of tebuconazole in different parts of banana were detected by high-performance liquid chromatography (HPLC) within 35 days. The mean recoveries and relative standard deviations in banana samples were 87.17 ~ 96.68% and 2.85 ~ 8.49%, respectively. The half-lives of tebuconazole in whole banana, banana pulp, and banana peel were 7.31 ~ 8.68 days, 11.12 ~ 13.39 days, and 4.06 ~ 5.74 days, respectively. It can be seen that tebuconazole dissipated fastest in the peel and slowest in the pulp. And the contents of tebuconazole in banana pulp and banana peel were 3 ~ 35% and 65 ~ 97%, respectively, which can be seen that tebuconazole was mainly distributed in the peel, and only a small part was transmitted to the pulp. Results also showed that the residual amounts of tebuconazole in banana pulp were increased at the first three days and then gradually dissipated, and were below the maximum residue limit (MRL) in China. The results of dietary intake risk assessment showed that the HQ (hazard quotient) were 0.45 ~ 2.69%, which were within the acceptable range. Overall, our research results show that tebuconazole in the field control of banana freckle disease has high security and low risk with the application dose of 133 g/L and diluted 1000 times in water, and can provide an important reference for the rational use of tebuconazole as a systemic fungicide in the field.

Residue dissipation and dietary risk assessment of cyazofamid and its metabolite CCIM in garlic, garlic bolt and garlic sprout

ABSTRACT The residue and dissipation dynamics of cyazofamid and its main metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM) in garlic, garlic bolt and garlic sprouts were investigated by QuEChERS high-performance liquid chromatography–tandem mass spectrometry method. Field experiments were conducted in 6 sites for one year. The dietary intake risk of cyazofamid was assessed. At different levels, the results showed that the average recoveries of cyazofamid were 89.8%–1005% in garlic, 84.6%–109.4% in garlic bolt and 88.6%–108.5% in garlic sprout, recoveries of CCIM were 84.6%–104.2% in garlic, 84.6%–108.9% in garlic bolt and 85.3%–109.2% in garlic sprout, respectively, with relative standard deviation less than 10.1%. The limits of quantitation were all 0.01 mg/kg. The dissipation dynamics of cyazofamid and CCIM in garlic plant matrices fitted the first order kinetic equation, and the half-lives were 3.5–6.1 d and 0.9–3.9 d, respectively. The dietary intake risk assessment showed that the dietary exposure risk index of cyazofamid in garlic, garlic bolt and garlic sprout were less than 100%, which indicated that the dietary exposure risk was at an acceptable level.

Residue and distribution of fosthiazate in cucumber (Cucumis sativus L.) and dietary intake risk assessment for various populations

ABSTRACT The safety and risk of fosthiazate as nematicide in cucumber field were evaluated in this study. An analytical method for determining the residues of fosthiazate in cucumber was developed. Mean recoveries and relative standard deviations in all samples ranged 85.3 ~ 95.0% and 5.7 ~ 13.3%. The half-lives of fosthiazate in cucumber root, leaf and fruit were 4.71 ~ 5.50 days, 3.52 ~ 4.78 days and 3.32 ~ 3.96 days. The residues in cucumber fruits were below the maximum residue limit (MRL) in China, based on the application dose of 900 g a.i./ha and the pre-harvest interval of 14 days. The transfer rates of fosthiazate from cucumber root to leaf were 17.48 ~ 46.03%, which were significantly higher than those of root to fruit (8.81 ~ 26.52%). These results indicated that fosthiazate was mainly distributed in cucumber root, and it was difficult to be absorbed by the fruit compared to the leaf. The long-term dietary intake risk assessment results showed that the risk quotient (RQ) ranged 20.04 ~ 36.25% and were less than 100%, which indicated that fosthiazate has a low risk for long-term dietary intake of cucumbers. Overall, our results would be considered as important references for safe and reasonable use of fosthiazate, monitoring and assessing the food safety, and protecting consumer health.

Terminal residue and dietary intake risk assessment of prothioconazole-desthio and fluoxastrobin in wheat field ecosystem.

Wheat is one of the most important cereal crops worldwide, and use of fungicides is an essential part of wheat production. Both prothioconazole and fluoxastrobin give excellent control of important seed and soilborne pathogens. The combination of these two fungicides shows a complementary mode of action and has a wide usage around the world. But the residue levels of these fungicides in the wheat matrix are still unknown. In the current study, a simple, low-cost and highly sensitive method using modified QuECHERS procedure combined with high-performance liquid chromatography-tandem mass spectrometry was developed to simultaneously quantify E- and Z-fluoxastrobin and the main metabolite prothioconazole-desthio of prothioconazole in the wheat matrix. The recoveries of prothioconazole-desthio, E-fluoxastrobin and Z-fluoxastrobin ranged from 84% to 101%, with relative standard deviation of less than 13.2%. The terminal residues of prothioconazole-desthio and E- and Z-fluoxastrobin were studied in wheat grain and straw under field conditions. The results showed that the terminal residue of the target compounds ranged from <0.01 to 0.029 mg kg-1 and <0.05 to 7.6mg kg-1 in wheat grain and straw (expressed as dry weight), respectively. The risk quotients of prothioconazole-desthio and fluoxastrobin were 0.2% and 3.2%. The residue levels of the target analytes in wheat grain were lower than the maximum residue limits recommended by the Chinese Ministry of Agriculture. And the calculated risk quotient values were far below 100%, indicating a low dietary intake health risk to consumers. © 2021 Society of Chemical Industry.

Residual behavior and dietary intake risk assessment of flonicamid, dinotefuran and its metabolites on peach trees.

Flonicamid and dinotefuran are widely applied to control pests and diseases in various economic crops arousing much public concerns about the potential risk to human health. In this study, the multi-determination and residual behavior of flonicamid-dinotefuran mixture on peach trees were investigated. The chronic risk of long-term dietary intake for Chinese consumers was evaluated. An optimized QuEChERS method combined with ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis for simultaneous determination of flonicamid, dinotefuran and its metabolites was established to analyze the residual dissipation and terminal residues in peach matrices. The results demonstrated that (i) a satisfactory linearity relationship with the detector response and the correlation coefficient R2 > 0.999, the average recoveries of these four analytes ranged from 94 to 108%, the relative standard deviation was between 1.0% and 8.8%, and the limit of the quantitation was 0.02 mg kg-1 ; (ii) the dissipation behaviors of flonicamid and dinotefuran followed with the first-order dynamic kinetics model, and the half-lives were 6.9-12.4 days and 8.1-15.1 days, respectively; (iii) the recommended preharvest interval (PHI) was 21 days, the risk quotient (RQ) values of flonicamid and dinotefuran were 16.6 and 20.7%, respectively, which were significantly less than 100%. The established analytical method met the detection requirement in terms of sensitivity, accuracy, and precision. Additionally, the results indicated that the potential dietary intake risk of the flonicamid-dinotefuran mixture on peach trees was negligible. This work can be utilized in the safe and responsible use of flonicamid-dinotefuran mixture and provide guidance for establishing its maximum residue limit (MRL) in China. © 2021 Society of Chemical Industry.

Determination and dietary intake risk assessment of 14 pesticide residues in apples of China

The presence of pesticide residues in apples raises serious health concerns. In this study, a novel, sensitive, high-performance method was developed to simultaneously analyze the residues of 14 pesticides in apples using modified QuEChERS sample pretreatment coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The optimized purification procedure demonstrated satisfactory recovery and precision for all the tested pesticides. The limits of detection (LOD) and quantification (LOQ) values of 14 pesticides in the apple matrix ranged from 0.03 μg/kg to 0.3 μg/kg and 0.1 μg/kg to 1.0 μg/kg, respectively. The proposed method detected six pesticides in the apple samples collected from 20 counties in China's major apple-producing regions. Furthermore, the risk quotient (RQ, %) of the detected pesticides was evaluated by the national estimated acceptable daily intake. The RQs of six pesticides in Chinese people of different age groups were less than 100%.

Residue dissipation and dietary intake risk assessment of thiophanate-methyl and its metabolite carbendazim in watercress under Chinese field conditions

ABSTRACT In this study,the QuEChERSand high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS)was applied to determine thiophanate-methyl and its metabolite carbendazim residue in watercress. The average recoveries of both analytes in watercress ranged from 96.2% to 102.9% with relative standard deviation (RSD) less than 8.2%. The limit of quantification (LOQ)of method for both analytes was 0.01 mg/kg. The field trials were carried out in 2018 to monitor the residues of thiophanate-methyl and its metabolite in six main cultivation areas inwatercressof China. Thiophanate-methylrapidly dissipated and transformed to carbendazim under watercress field conditions with half-lives less than 2.12 d.Carbendazim also rapidly dissipated with half-lives of 2.76 and 3.77d at two experiment sites. The terminal residue of thiophanate-methyl,carbendazim and total thiophanate-methyl were lower than 14.5 mg/kg, 5.26 mg/kg and 13.3 mg/kg, respectively. In order to ensure the safety, the acute and chronic dietary intake risks were evaluated. The ADI%of thiophanate-methyl, carbendazim and total thiophanate-methyl ranged from 21.1% to 84.9% and their%ARfDranged from 2.1% to 19.2%, which suggested that thiophanate-methyl and carbendazim has a low risk for Chinese populations caused by application of thiophanate-methyl.