A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were deve...A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were developed.The samples were extracted with acetonitrile/acetic acid(99:1,V/V),and clean-up by SinChERS-Nano(single-step,cheap,effective,rugged,safe,nano)column,determined by UPLC-Q-TOF/MS.The accurate mass database and MS/MS database which contains 420 pesticides were established,the automatic retrieval of detection results was carried on according to the accurate mass,retention time,isotope ratio,ion fragment information,and so on.Method verification was performed on leeks samples.The results showed that 420 pesticides had good linearity in the range of 0.1-100μg/L,and the correlation coeffificients(R2)was greater than 0.990.The limits of detections(LODs)and limits of quantifications(LOQs)of 420 pesticides were in range of 0.05-2.0 and 0.1-5.0μg/L,respectively.The average spike recoveries at 3 levels were 70.1%to 119.7%,and the relative standard deviations(RSD)were lower than 20%(n=6).With this method,a survey of pesticide residues was conducted for 110 samples of 10 different fruits and vegetables,which provided scientific data for ensuring pesticide residue safety of the fruits and vegetables consumed daily by the public.This method was simple,sensitive and accurate,and could be used for rapid screening of 420 pesticide residues in fruits and vegetables.展开更多
[Objectives]This study was conducted to understand the status of pesticide residues and dietary intake risk of Chinese chives in Tangshan area. [Methods] Sixty eight kinds of pesticide residues in 415 Chinese chive sa...[Objectives]This study was conducted to understand the status of pesticide residues and dietary intake risk of Chinese chives in Tangshan area. [Methods] Sixty eight kinds of pesticide residues in 415 Chinese chive samples collected from Tangshan area were qualitatively and quantitatively determined by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) and gas chromatography(GC) in 2020. [Results] The results showed that 41 kinds of pesticide residues were detected in the 415 Chinese chive samples, and the detection rate was 69.4%(288/415), and there was a combination of pesticides in many samples. According to the National Food Safety Standard―Maximum Residue Limits of Pesticides in Food(GB 2763-2019), the residues of 12 pesticides exceeded the maximum residue limits(MRLs), and the unqualified rate was 38.07%(158/415). The highest detection rate of clothianidin was 41.20%(171/415), but there was no MRL in GB 2763-2019. The next was procymidone, the detection rate of which was 35.42%(147/415), and the over-standard rate was 30.12%(125/415). Forbidden and restricted pesticides were detected in some samples. According to the dietary exposure risk assessment, the NEDI/ADI values were all less than 1 and the intake risk was within acceptable range. In Tangshan area, the types of pesticides used in Chinese chive production are complex, and there are risks of multi-residue pollution and use of banned and restricted pesticides and unregistered pesticides. It is suggested that routine monitoring of pesticide residues and management of pesticide use should be strengthened to ensure the quality and safety of agricultural products. [Conclusions] This study provides a theoretical basis for the safe production of Chinese chive and the standardized and rational use of pesticides.展开更多
Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus,However,rarely studies focus on the rapid determination of these residues.Here,a total of 30 kinds of...Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus,However,rarely studies focus on the rapid determination of these residues.Here,a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry(UPLC-MS/MS)in five different process ways.Pretreatment methods,chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly.Among the five different pretreatment methods,the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds(both lower than 60%).Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method(QuEChERS)was lower than 60%,which did not meet the requirements of trace determination.The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges,with correlation coefficients over 0.99.The average recoveries of straightforward ranged from 78.13%to 110.9%,while RSD ranged from 1.3%to 16.9%,albeit poor purification was observed.The recovery yield from solid phase extraction was between 67.75%and 103.08%with RSD value from 0.8%to 14.0%,which met the requirements of trace determination,this method has good precision and stability.These results could be employed to other Traditional Chinese Medicines(TCMs)in detecting prohibited pesticide residues.展开更多
[Objectives]This study was conducted to investigate the pesticide residue status of bananas in Tangshan area and the dietary intake risk of consumers.[Methods]High-performance liquid chromatography-tandem mass spectro...[Objectives]This study was conducted to investigate the pesticide residue status of bananas in Tangshan area and the dietary intake risk of consumers.[Methods]High-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was applied to detect 70 pesticide residues in 191 batches of banana samples extracted from Tangshan area,and chronic and acute risk assessments were conducted.[Results]Among the 191 batches of bananas,172 batches of samples were detected to contain agrochemicals,with a detection rate of 90.05%.Seventeen agrochemicals were detected,accounting for 24.29%of the total agrochemicals tested.There was a phenomenon of multiple pesticide residues in a single sample,and high detection rates were found in carbendazim(49.21%),prochloraz(41.88%),pyraclostrobin(34.03%)and imidacloprid(30.37%).According to GB 2763-2021 National Food Safety Standards—Maximum Residue Limits for Pesticides in Food,the over-standard rate of imidacloprid was 17.8%;and the chronic and acute dietary risks of the 17 pesticide residues were all less than 100%.[Conclusions]The pesticide residues in bananas consumed by consumers on a daily basis do not pose unacceptable dietary risks.展开更多
[Objectives]The paper was to establish a rapid screening method of pesticide residues in strawberry based on HPLC-QTOF/MS SWATH acquisition mode.[Methods]The strawberry sample was extracted with acetonitrile,purified ...[Objectives]The paper was to establish a rapid screening method of pesticide residues in strawberry based on HPLC-QTOF/MS SWATH acquisition mode.[Methods]The strawberry sample was extracted with acetonitrile,purified with anhydrous magnesium sulfate,sodium chloride and primary secondary amine(PSA)powder,and then loaded on the machine.The full information spectrum was collected by positive ion mode and screened by comparing with the spectrum library,and 20 kinds of pesticide residues were quantitatively analyzed.[Results]The detection limits of 20 pesticide residues were 0.0002-0.0100 mg/kg,and they showed good linearity in the range of 0.0005-0.1000μg/mL(R 2≥0.995).The recoveries ranged from 62.8%to 106.3%.[Conclusions]This method is rapid,simple,sensitive and non-targeted,and can be used for rapid screening of multiple pesticide residues in strawberry.展开更多
To ensure the safety of the commercially available chenpi,a convenient and fast analytical method was developed for the determination of 133 pesticide residues in chenpi using gas chromatography-tandem mass spectromet...To ensure the safety of the commercially available chenpi,a convenient and fast analytical method was developed for the determination of 133 pesticide residues in chenpi using gas chromatography-tandem mass spectrometry(GC-MS/MS).In this study,different extraction solvents,redissolution solvents and adsorbents were tested according to the recovery and purification effect to obtain a modified QuEChERS method.The samples were extracted with acetonitrile.During the clean-up step,octadecyl-modified silica(C18)and graphitized carbon black(GCB)were selected,and aminopropyl(NH2)was used instead of primary secondary amine(PSA)because of its weaker ion exchange capacity which had little effect on the recovery of ditalimfos.Samples were quantified by matrix-matched calibration with internal standards.All pesticides showed good linearity in the respective range,both with values of r2>0.99.The average recoveries of the pesticides spiked samples ranged from 70.0% to 112.2% with the RSDs of 0.2%–14.4%.The modified QuEChERS method was validated and applied to twenty real samples.Five pesticides were found in eight batches,but no pesticide exceeded the maximum residue limits(MRL,MRL reference to European commission).展开更多
This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 b...This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 batches of market samples in China.The samples were extracted with acetonitrile,cleaned up with primary secondary amine(PSA)and octadecylsilane(C18)and determined by GC-MS/MS in multiple reaction monitoring(MRM)mode.Matrix-matched calibration was recommended to combat the matrix effect.A good linearity was observed in the range of 10−500 ng/mL with correlation coefficients≥0.9950.The mean recoveries for most of the pesticides were in the range of 70%−120%with RSD<20%.The limits of detection ranged 0.28–2.00μg/kg,while the limits of quantification were 0.94–6.65μg/kg.Following the application of“top-down”approach,the expanded measurement uncertainty for all the analytes was<30%.The proposed method was successfully applied to determine pesticide residues in 20 market samples in China,where 9 pesticides were detected and quintozene exceeded the criteria domestically and abroad.展开更多
In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purificatio...In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.展开更多
[ Objectives] This study was conducted to establish a QuEChERS-gas chromatography method for determination of eight kinds of organophosphorus pesticide residues in pepper. [Methods] The samples were extracted by aceto...[ Objectives] This study was conducted to establish a QuEChERS-gas chromatography method for determination of eight kinds of organophosphorus pesticide residues in pepper. [Methods] The samples were extracted by acetonitrile, and anhydrous magnesium sulfate was used for salting out. The extracts were then purified by dispersive solid phase extraction combining with GCB, C18 and PSA. Samples were analyzed by FPD detector. External standard was used as quantitive method. [ Results] The detection limits were in the range of 0. 001 -0. 008 mg/kg, the average recoveries ranged from 83.5% to 101.2% , and the relative standard deviation (RSD) of the eight organophosphorus pesticide residues were below 5%. [ Conclusions] The method is simple, quick, easy and effective for the determination of pepper.展开更多
In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of ...In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of pesticide residues in vegetables was explored, and the variability factor was calculated. The level of pesticide residue was studied by statistical method. The variability factor was calculated using the Harrell-Davis method in accordance with principles recommended by the JMPR. In addition, the procedure of evaluation was validated according to the principles laid down by the JMPR (Joint Meeting on Pesticide Residues). The detection rate of pesticide residues in all marketplace samples was less than 20% in Jinan City. The unqualified rate of vegetables was low (0.6%). The chlorothalonil was found as the pesticide with the highest rate of detection. The vegetables with the highest rate of pesticide residues detected were leafy vegetables. The relationship between variability factor and mean value of concentrations of contaminations was expressed by the formula, v=4.9×Cmean. The pesticide residues in vegetables from Jinan City is low. The evaluated variability factor is larger than that the value recommended by the JMPR, however, less than the default value used for acute intake assessment of pesticide residues in UK in most cases.展开更多
As pesticide residues in bayberry has raised serious concern from the public in China, a monitoring survey was carried out during 2013–2014 and 157 samples were analyzed in total. Twenty-three pesticides were detecte...As pesticide residues in bayberry has raised serious concern from the public in China, a monitoring survey was carried out during 2013–2014 and 157 samples were analyzed in total. Twenty-three pesticides were detected among the 44 pesticides analyzed and at least one pesticide was detected in 63% of 99 samples. Whereas 45.6% of samples were found with two or more pesticide residues, and 23.6% of samples with four or more pesticide residues. Probabilistic risk assessments indicated that estimated daily intake(EDI) of cyhalothrin at the P97.5th percentile level is 1.11 times larger than the acceptable daily intake(ADI) for children, the estimated short-term intake(ESTI) at the P97.5th percentile level is 1.9 and 1.78 times larger than the acute reference dose(ARf D) for adult and children, respectively, indicating the potential risk concern from pyrethroids. EDI of the pesticides with anti-androgenic effects ranged from 0.15–2.46 of ADI, the probability of exposure exceeding the ADI was 7.1 and 31.1% for adults and children, respectively, the probability of exposure of pyrethroids exceeding the ADI was 3.8% for children. Exposures for other pesticides and groups were below 1.0. Because the co-occurrence of frequency of cyhalothrin and cypermethrin was 9.55%, the combinations of pesticides detected with anti-androgenic effects has not been found in the present monitoring, the results indicate that the pesticide residues in bayberry will not constitute serious public health risk, however, they are significant for the management of pesticide use on bayberry and dietary health risk in China.展开更多
This paper covers the monitoring activities of organochlorine (OCS) pesticide residues in the GEMS/Food program, which China took part in for the first time in 1992. The levels of HCH and DDT were determined in 355 sa...This paper covers the monitoring activities of organochlorine (OCS) pesticide residues in the GEMS/Food program, which China took part in for the first time in 1992. The levels of HCH and DDT were determined in 355 samples of eight main varieties of food , taken from five provinces and cities. The results show that the positive rate of HCH is 69%, of which 99. 44 % is in accord with the National Standards of Food Hygiene of China. As to DDT, the two rates are 42 % and 100 % respectively. The daily intakes of HCH and DDT are 0. 22 mg/ kg.bw and 0. 54 mg/kg. bw respectively, which are far below their corresponding ADIs.Compared with those in 1970s, the OCS residues have decreased significantly. Therefore the monitored varieties of food are safe to people's health展开更多
[Objectives] To establish Qu ECh ERS based extraction method for determining multiple pesticide residues in okra combined with programmed temperature vaporizer-gas chromatography-triple quadrupole mass spectrometry( P...[Objectives] To establish Qu ECh ERS based extraction method for determining multiple pesticide residues in okra combined with programmed temperature vaporizer-gas chromatography-triple quadrupole mass spectrometry( PTV-GC-MS/MS) and ultra high performance liquid chromatography-mass spectrometry( UPLC-MS/MS). [Methods] In this experiment,124 pesticide residues in okra were determined by an optimized Qu ECh ERS method combined with PTV-GC-MS/MS and UPLC-MS/MS. The pesticides in okra were extracted and purified by the optimized Qu ECh ERS pretreatment method and determined by PTV-GC-MS/MS and UPLC-MS/MS. [Results] In this experiment,124 kinds of pesticides had a good linearity with a limit of detection( LOD) of 0. 000 5-0. 008 0 mg/kg; the average recovery rate at three levels was 65. 5%-128. 1% with relative standard deviation of 2. 2%-9. 7%. [Conclusions] This method is simple,rapid,accurate and sensitive,and can provide reliable and valid data support for the determination of multiple pesticide residues in okra by GC-MS/MS and UPLC-MS/MS.展开更多
The increasing application of pesticides for agricultural purposes involves serious risk to the environment and human health due to either exposure or through residues in food and drinking water. Since food safety is ...The increasing application of pesticides for agricultural purposes involves serious risk to the environment and human health due to either exposure or through residues in food and drinking water. Since food safety is of mandatory importance there is a growing interest on the development of selective, simple, rapid, cost-effective and reliable analytical methodologies in order to ensure that pesticides residues should not be found at levels above the established maximum pesticide residue limits (MRLs). In recent years, a new methodology based on the development of molecularly imprinting polymers (MIPs) allows not only pre-concentration and cleaning of the sample but also selective extraction of the target analyte, which is crucial, particularly when the sample is complex and impurities can interfere with quantification. The scope of this review is to provide a general overview on MIPs field, with emphasis on MIP preparation and its use as sorbents for solid-phase extraction. This paper will be focused on the review of the current state of the art in the use of MIPs as selective materials in molecularly imprinted solid-phase extraction (MISPE) for the analysis of pesticide residues from food matrices. A review of preparation and application of MIPs in food matrices, will also be discussed.展开更多
Pesticide residues are either natural or synthetic and are found in most edible products such as fresh fruits, vegetables, meat and other processed products. Excess of these pesticides’ residues is unsafe for consump...Pesticide residues are either natural or synthetic and are found in most edible products such as fresh fruits, vegetables, meat and other processed products. Excess of these pesticides’ residues is unsafe for consumption due to regulatory measures. Thus, it is beneficial to assess the level of residues of pesticides in the food diet in order to improve the standard of living of the population. This study intends to assess the pesticide usage and residue levels of selected pesticides in fresh tomatoes in the supply chain of Rwanda. The results of the study confirm that there are around 10 brands of pesticides used in Rwanda. 58.97% of the surveyed people around the country are males and 71.79% of farmers apply rockets as the main pesticide. More than 22% of surveyed farmers affirmed to consume the raw or/and unwashed tomatoes. This study revealed that the residues of the active ingredients contained in the pesticides are accumulated in unwashed tomatoes and the quantity of such residues is shown in this study. Deltamethrin was 0.64 ± 0. 009 mg·kg<sup>?</sup><sup>1</sup> in tomatoes collected in Rusizi district, cypermethrin 1.1435 ± 0. 0375 mg·kg<sup>?1</sup> in tomatoes collected from Gisagara District, mancozeb residues was 0.620 ± 0.000 mg·kg<sup>?1</sup> in tomatoes collected from Rusizi district. The results of the study also show that pesticide residues are not found in the washed tomatoes. Therefore, the detection of pesticide residues in unwashed tomatoes in some samples indicates the malpractice of residues among farmers in Rwanda. Also, consumers eating the unwashed fresh tomatoes are recommended to wash the tomatoes before use.展开更多
[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues...[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.展开更多
Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs...Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of Côte d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding.展开更多
Based on the chemical properties of dithiocarbamate pesticides,a device for rapid detection was developed in the paper,and the experimental conditions were optimized. Dithiocarbamate residues in fruits were successful...Based on the chemical properties of dithiocarbamate pesticides,a device for rapid detection was developed in the paper,and the experimental conditions were optimized. Dithiocarbamate residues in fruits were successfully detected using molecular absorption spectro-photometry,and the recovery rate was over 80%.The rapid detection method was simple to operate with low cost,and was conducive to application in basic level and enterprise laboratories.展开更多
The presence of pesticide residues in pears is a serious health concern. This study presents the results from a 2-year investigation (2013-2014) that used gas chromatography, GS/MS and UPLC/MS-MS to measure the leve...The presence of pesticide residues in pears is a serious health concern. This study presents the results from a 2-year investigation (2013-2014) that used gas chromatography, GS/MS and UPLC/MS-MS to measure the levels of 104 pesti- cides in 310 pear samples. In 93.2% of the samples, 43 pesticides were detected, of which the maximum residue levels (MRLs) were exceeded in 2.6% of the samples. Multiple residues (two to eight compounds) were present in 69.7% of the samples; one sample contained nine pesticides and one sample contained 10. Only 6.8% of the samples did not contain residues. To assess the health risks, the pesticide residue data have been combined with daily pear consumption data for children and adult populations. A deterministic model was used to assess the chronic and acute exposures based on the Joint Meeting on Pesticide Residues (JMPR) method. A potential acute risk was demonstrated for children in the case of bifenthrin, which was found to be present at 105.36% of the acute reference dose (ARfD) value. The long- term exposure of the Chinese consumer to pesticide residues through the consumption of raw pears was far below the acceptable daily intake (ADI) criterion. Additionally, the matrix ranking scheme was used to classify risk subgroups of pesticides and pear samples. In general, 95.5% of samples were deemed to be safe and nine pesticides were classified as being of a relatively high risk. The findings indicated that the occurrence of pesticide residues in pears should not be considered a serious public health problem. Nevertheless, a more detailed study is required for vulnerable consumer groups, especially children. Continuous monitoring of pesticides in pears and tighter regulation of pesticide residue standards are recommended.展开更多
Plant pesticide residues, such as chinaberry (Melia toosendan) residue and sand cypress (Sabina vulgaris) residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with or...Plant pesticide residues, such as chinaberry (Melia toosendan) residue and sand cypress (Sabina vulgaris) residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with organic solvents. The only option for botanical pesticide residue utilization has been as landfill. Chinaberry residue (CBR) and sand cypress residue (SCR) were collected and composted in Yangling, Shaanxi Province, China. We studied the effects of chinaberry residue compost (CBRC), CBRC incorporated with Trichoderma viride (CBRCT), sand cypress residue compost (SCRC), and SCRC incorporated with T. viride (SCRCv) on the root-knot nematode, Meloidogyne incognita, infesting the balloonflower (Platycodon grandiflorum). Bioassay results indicated that stock solutions of the CBRCT and SCRCT extracts significantly inhibited egg hatching and caused high larval mortality, followed in degree by the CBRC and SCRC extracts. The CBR and SCR extracts caused very low inhibition of eggs and larvae. Supplementing potting mixtures with these four composts reduced the severity of root galling and increased the proportion of marketable roots. The severity of root galling decreased and the average weight of the marketable roots increased with an increase in all the composts when supplemented at rates from 5 to 30%. CBR- and SCR-supplemented pot soils also inhibited the nematodes, but CBR and SCR applied to the soil had a phytotoxic effect and inhibited balloonflower growth. Supplementing field soil with the composts reduced the severity of root galling and the populations of southern root-knot nematodes in the soil. CBRCT and SCRCT clearly enhanced the average weight of the marketable roots by 30.45 and 26.64%, respectively. Continuous supplementation with CBRCT or SCRCT in the same field significantly enhanced the control of the root-knot nematode, and the populations of nematodes continued to decrease with second inoculations. The populations of total Trichoderma spp. were distinctly enhanced and were maintained at high levels for a long time in the supplemented soils.展开更多
基金supported by National Key Research and Development Program of China(2018YFC1603400)Special Technical Support Project of State Administration for Market Regulation(2019YJ009).
文摘A new method for screening and identification 420 pesticide residues in fruits and vegetables by ultra-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS)were developed.The samples were extracted with acetonitrile/acetic acid(99:1,V/V),and clean-up by SinChERS-Nano(single-step,cheap,effective,rugged,safe,nano)column,determined by UPLC-Q-TOF/MS.The accurate mass database and MS/MS database which contains 420 pesticides were established,the automatic retrieval of detection results was carried on according to the accurate mass,retention time,isotope ratio,ion fragment information,and so on.Method verification was performed on leeks samples.The results showed that 420 pesticides had good linearity in the range of 0.1-100μg/L,and the correlation coeffificients(R2)was greater than 0.990.The limits of detections(LODs)and limits of quantifications(LOQs)of 420 pesticides were in range of 0.05-2.0 and 0.1-5.0μg/L,respectively.The average spike recoveries at 3 levels were 70.1%to 119.7%,and the relative standard deviations(RSD)were lower than 20%(n=6).With this method,a survey of pesticide residues was conducted for 110 samples of 10 different fruits and vegetables,which provided scientific data for ensuring pesticide residue safety of the fruits and vegetables consumed daily by the public.This method was simple,sensitive and accurate,and could be used for rapid screening of 420 pesticide residues in fruits and vegetables.
基金Supported by The Fourth Batch of High-end Talent Project in Hebei ProvinceTangshan Science and Technology Entrepreneurship and Innovation Leading Talent ProjectFund for the Central Government to Guide Local Scientific and Technological Development (226Z5504G)。
文摘[Objectives]This study was conducted to understand the status of pesticide residues and dietary intake risk of Chinese chives in Tangshan area. [Methods] Sixty eight kinds of pesticide residues in 415 Chinese chive samples collected from Tangshan area were qualitatively and quantitatively determined by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) and gas chromatography(GC) in 2020. [Results] The results showed that 41 kinds of pesticide residues were detected in the 415 Chinese chive samples, and the detection rate was 69.4%(288/415), and there was a combination of pesticides in many samples. According to the National Food Safety Standard―Maximum Residue Limits of Pesticides in Food(GB 2763-2019), the residues of 12 pesticides exceeded the maximum residue limits(MRLs), and the unqualified rate was 38.07%(158/415). The highest detection rate of clothianidin was 41.20%(171/415), but there was no MRL in GB 2763-2019. The next was procymidone, the detection rate of which was 35.42%(147/415), and the over-standard rate was 30.12%(125/415). Forbidden and restricted pesticides were detected in some samples. According to the dietary exposure risk assessment, the NEDI/ADI values were all less than 1 and the intake risk was within acceptable range. In Tangshan area, the types of pesticides used in Chinese chive production are complex, and there are risks of multi-residue pollution and use of banned and restricted pesticides and unregistered pesticides. It is suggested that routine monitoring of pesticide residues and management of pesticide use should be strengthened to ensure the quality and safety of agricultural products. [Conclusions] This study provides a theoretical basis for the safe production of Chinese chive and the standardized and rational use of pesticides.
文摘Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus,However,rarely studies focus on the rapid determination of these residues.Here,a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry(UPLC-MS/MS)in five different process ways.Pretreatment methods,chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly.Among the five different pretreatment methods,the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds(both lower than 60%).Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method(QuEChERS)was lower than 60%,which did not meet the requirements of trace determination.The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges,with correlation coefficients over 0.99.The average recoveries of straightforward ranged from 78.13%to 110.9%,while RSD ranged from 1.3%to 16.9%,albeit poor purification was observed.The recovery yield from solid phase extraction was between 67.75%and 103.08%with RSD value from 0.8%to 14.0%,which met the requirements of trace determination,this method has good precision and stability.These results could be employed to other Traditional Chinese Medicines(TCMs)in detecting prohibited pesticide residues.
基金Supported by The Fourth Batch of High-end Talent Project in Hebei ProvinceHebei Provincial Science and Technology Innovation Leading Talents(21130243A).
文摘[Objectives]This study was conducted to investigate the pesticide residue status of bananas in Tangshan area and the dietary intake risk of consumers.[Methods]High-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was applied to detect 70 pesticide residues in 191 batches of banana samples extracted from Tangshan area,and chronic and acute risk assessments were conducted.[Results]Among the 191 batches of bananas,172 batches of samples were detected to contain agrochemicals,with a detection rate of 90.05%.Seventeen agrochemicals were detected,accounting for 24.29%of the total agrochemicals tested.There was a phenomenon of multiple pesticide residues in a single sample,and high detection rates were found in carbendazim(49.21%),prochloraz(41.88%),pyraclostrobin(34.03%)and imidacloprid(30.37%).According to GB 2763-2021 National Food Safety Standards—Maximum Residue Limits for Pesticides in Food,the over-standard rate of imidacloprid was 17.8%;and the chronic and acute dietary risks of the 17 pesticide residues were all less than 100%.[Conclusions]The pesticide residues in bananas consumed by consumers on a daily basis do not pose unacceptable dietary risks.
基金Supported by Scientific Research Project of General Administration of Customs (2021DK16).
文摘[Objectives]The paper was to establish a rapid screening method of pesticide residues in strawberry based on HPLC-QTOF/MS SWATH acquisition mode.[Methods]The strawberry sample was extracted with acetonitrile,purified with anhydrous magnesium sulfate,sodium chloride and primary secondary amine(PSA)powder,and then loaded on the machine.The full information spectrum was collected by positive ion mode and screened by comparing with the spectrum library,and 20 kinds of pesticide residues were quantitatively analyzed.[Results]The detection limits of 20 pesticide residues were 0.0002-0.0100 mg/kg,and they showed good linearity in the range of 0.0005-0.1000μg/mL(R 2≥0.995).The recoveries ranged from 62.8%to 106.3%.[Conclusions]This method is rapid,simple,sensitive and non-targeted,and can be used for rapid screening of multiple pesticide residues in strawberry.
文摘To ensure the safety of the commercially available chenpi,a convenient and fast analytical method was developed for the determination of 133 pesticide residues in chenpi using gas chromatography-tandem mass spectrometry(GC-MS/MS).In this study,different extraction solvents,redissolution solvents and adsorbents were tested according to the recovery and purification effect to obtain a modified QuEChERS method.The samples were extracted with acetonitrile.During the clean-up step,octadecyl-modified silica(C18)and graphitized carbon black(GCB)were selected,and aminopropyl(NH2)was used instead of primary secondary amine(PSA)because of its weaker ion exchange capacity which had little effect on the recovery of ditalimfos.Samples were quantified by matrix-matched calibration with internal standards.All pesticides showed good linearity in the respective range,both with values of r2>0.99.The average recoveries of the pesticides spiked samples ranged from 70.0% to 112.2% with the RSDs of 0.2%–14.4%.The modified QuEChERS method was validated and applied to twenty real samples.Five pesticides were found in eight batches,but no pesticide exceeded the maximum residue limits(MRL,MRL reference to European commission).
基金the National Key Research and Development Plan of China(2017YFC1702500).
文摘This study established a method for the simultaneous determination of 74 pesticide residues in Panax notoginseng by QuEChERS pretreatment method coupled with GC-MS/MS,and carried out pesticide residue analysis on 20 batches of market samples in China.The samples were extracted with acetonitrile,cleaned up with primary secondary amine(PSA)and octadecylsilane(C18)and determined by GC-MS/MS in multiple reaction monitoring(MRM)mode.Matrix-matched calibration was recommended to combat the matrix effect.A good linearity was observed in the range of 10−500 ng/mL with correlation coefficients≥0.9950.The mean recoveries for most of the pesticides were in the range of 70%−120%with RSD<20%.The limits of detection ranged 0.28–2.00μg/kg,while the limits of quantification were 0.94–6.65μg/kg.Following the application of“top-down”approach,the expanded measurement uncertainty for all the analytes was<30%.The proposed method was successfully applied to determine pesticide residues in 20 market samples in China,where 9 pesticides were detected and quintozene exceeded the criteria domestically and abroad.
基金National Key Research and Development Program of China(Project No.2018YFC1603400)Science and Technology Program of Hebei Province(Project No.19225503D)Technical Support Project of State Administration for Market Regulation(Project No.2019YJ009).
文摘In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.
基金Supported by Post-doctoral Scientific Fund of China(No.2017M611382)Autonomy Program of Economy,Trade and Information Commission of Shenzhen Municipality(No.20170427160059840)
文摘[ Objectives] This study was conducted to establish a QuEChERS-gas chromatography method for determination of eight kinds of organophosphorus pesticide residues in pepper. [Methods] The samples were extracted by acetonitrile, and anhydrous magnesium sulfate was used for salting out. The extracts were then purified by dispersive solid phase extraction combining with GCB, C18 and PSA. Samples were analyzed by FPD detector. External standard was used as quantitive method. [ Results] The detection limits were in the range of 0. 001 -0. 008 mg/kg, the average recoveries ranged from 83.5% to 101.2% , and the relative standard deviation (RSD) of the eight organophosphorus pesticide residues were below 5%. [ Conclusions] The method is simple, quick, easy and effective for the determination of pepper.
基金supports received from the National Key Technology R&D Program in the 11th Five-Year Plan of China (2006BAK02A04-06)Technological Innovation Fund of the Shandong Academy of Agricultural Sciences (2006ycx034)
文摘In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of pesticide residues in vegetables was explored, and the variability factor was calculated. The level of pesticide residue was studied by statistical method. The variability factor was calculated using the Harrell-Davis method in accordance with principles recommended by the JMPR. In addition, the procedure of evaluation was validated according to the principles laid down by the JMPR (Joint Meeting on Pesticide Residues). The detection rate of pesticide residues in all marketplace samples was less than 20% in Jinan City. The unqualified rate of vegetables was low (0.6%). The chlorothalonil was found as the pesticide with the highest rate of detection. The vegetables with the highest rate of pesticide residues detected were leafy vegetables. The relationship between variability factor and mean value of concentrations of contaminations was expressed by the formula, v=4.9×Cmean. The pesticide residues in vegetables from Jinan City is low. The evaluated variability factor is larger than that the value recommended by the JMPR, however, less than the default value used for acute intake assessment of pesticide residues in UK in most cases.
基金supported by the National Natural Science Foundation of China(31301490)the Zhejiang Provincial Major Scientific and Technology Project for Agriculture,China(2015C02043)the Zhejiang Provincial Major Scientific and Research Project for Agriculture,China(ZJNY2017001)
文摘As pesticide residues in bayberry has raised serious concern from the public in China, a monitoring survey was carried out during 2013–2014 and 157 samples were analyzed in total. Twenty-three pesticides were detected among the 44 pesticides analyzed and at least one pesticide was detected in 63% of 99 samples. Whereas 45.6% of samples were found with two or more pesticide residues, and 23.6% of samples with four or more pesticide residues. Probabilistic risk assessments indicated that estimated daily intake(EDI) of cyhalothrin at the P97.5th percentile level is 1.11 times larger than the acceptable daily intake(ADI) for children, the estimated short-term intake(ESTI) at the P97.5th percentile level is 1.9 and 1.78 times larger than the acute reference dose(ARf D) for adult and children, respectively, indicating the potential risk concern from pyrethroids. EDI of the pesticides with anti-androgenic effects ranged from 0.15–2.46 of ADI, the probability of exposure exceeding the ADI was 7.1 and 31.1% for adults and children, respectively, the probability of exposure of pyrethroids exceeding the ADI was 3.8% for children. Exposures for other pesticides and groups were below 1.0. Because the co-occurrence of frequency of cyhalothrin and cypermethrin was 9.55%, the combinations of pesticides detected with anti-androgenic effects has not been found in the present monitoring, the results indicate that the pesticide residues in bayberry will not constitute serious public health risk, however, they are significant for the management of pesticide use on bayberry and dietary health risk in China.
文摘This paper covers the monitoring activities of organochlorine (OCS) pesticide residues in the GEMS/Food program, which China took part in for the first time in 1992. The levels of HCH and DDT were determined in 355 samples of eight main varieties of food , taken from five provinces and cities. The results show that the positive rate of HCH is 69%, of which 99. 44 % is in accord with the National Standards of Food Hygiene of China. As to DDT, the two rates are 42 % and 100 % respectively. The daily intakes of HCH and DDT are 0. 22 mg/ kg.bw and 0. 54 mg/kg. bw respectively, which are far below their corresponding ADIs.Compared with those in 1970s, the OCS residues have decreased significantly. Therefore the monitored varieties of food are safe to people's health
基金Supported by Science and Technology Planning Project of Guangdong Province(2014A040401008)
文摘[Objectives] To establish Qu ECh ERS based extraction method for determining multiple pesticide residues in okra combined with programmed temperature vaporizer-gas chromatography-triple quadrupole mass spectrometry( PTV-GC-MS/MS) and ultra high performance liquid chromatography-mass spectrometry( UPLC-MS/MS). [Methods] In this experiment,124 pesticide residues in okra were determined by an optimized Qu ECh ERS method combined with PTV-GC-MS/MS and UPLC-MS/MS. The pesticides in okra were extracted and purified by the optimized Qu ECh ERS pretreatment method and determined by PTV-GC-MS/MS and UPLC-MS/MS. [Results] In this experiment,124 kinds of pesticides had a good linearity with a limit of detection( LOD) of 0. 000 5-0. 008 0 mg/kg; the average recovery rate at three levels was 65. 5%-128. 1% with relative standard deviation of 2. 2%-9. 7%. [Conclusions] This method is simple,rapid,accurate and sensitive,and can provide reliable and valid data support for the determination of multiple pesticide residues in okra by GC-MS/MS and UPLC-MS/MS.
基金funding by Fundos FEDER through Programa Operacional Factores de Competitividade-COM-PETE and Fundos Nacionais through FCT-Fundacao para a Ciencia e a Tecnologia(Project PTDC/AGR-ALI/117544/2010).
文摘The increasing application of pesticides for agricultural purposes involves serious risk to the environment and human health due to either exposure or through residues in food and drinking water. Since food safety is of mandatory importance there is a growing interest on the development of selective, simple, rapid, cost-effective and reliable analytical methodologies in order to ensure that pesticides residues should not be found at levels above the established maximum pesticide residue limits (MRLs). In recent years, a new methodology based on the development of molecularly imprinting polymers (MIPs) allows not only pre-concentration and cleaning of the sample but also selective extraction of the target analyte, which is crucial, particularly when the sample is complex and impurities can interfere with quantification. The scope of this review is to provide a general overview on MIPs field, with emphasis on MIP preparation and its use as sorbents for solid-phase extraction. This paper will be focused on the review of the current state of the art in the use of MIPs as selective materials in molecularly imprinted solid-phase extraction (MISPE) for the analysis of pesticide residues from food matrices. A review of preparation and application of MIPs in food matrices, will also be discussed.
文摘Pesticide residues are either natural or synthetic and are found in most edible products such as fresh fruits, vegetables, meat and other processed products. Excess of these pesticides’ residues is unsafe for consumption due to regulatory measures. Thus, it is beneficial to assess the level of residues of pesticides in the food diet in order to improve the standard of living of the population. This study intends to assess the pesticide usage and residue levels of selected pesticides in fresh tomatoes in the supply chain of Rwanda. The results of the study confirm that there are around 10 brands of pesticides used in Rwanda. 58.97% of the surveyed people around the country are males and 71.79% of farmers apply rockets as the main pesticide. More than 22% of surveyed farmers affirmed to consume the raw or/and unwashed tomatoes. This study revealed that the residues of the active ingredients contained in the pesticides are accumulated in unwashed tomatoes and the quantity of such residues is shown in this study. Deltamethrin was 0.64 ± 0. 009 mg·kg<sup>?</sup><sup>1</sup> in tomatoes collected in Rusizi district, cypermethrin 1.1435 ± 0. 0375 mg·kg<sup>?1</sup> in tomatoes collected from Gisagara District, mancozeb residues was 0.620 ± 0.000 mg·kg<sup>?1</sup> in tomatoes collected from Rusizi district. The results of the study also show that pesticide residues are not found in the washed tomatoes. Therefore, the detection of pesticide residues in unwashed tomatoes in some samples indicates the malpractice of residues among farmers in Rwanda. Also, consumers eating the unwashed fresh tomatoes are recommended to wash the tomatoes before use.
基金Development of Huotanmu Capsules,a New Zhuang Ethnic Medicine for the Treatment of Hepatitis B(20183046-1)Collaborative Innovation Center of Zhuang and Yao Ethnic Medicine(GJKY[2013]20)+2 种基金Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicines(GKJZ[2014]32)Guangxi Key Discipline:Zhuang Pharmacology(GJKY[2013]16)First-class Discipline in Guangxi of Traditional Chinese Pharmacology(Direction of Ethnic Medicine)(GJKY[2018]12).
文摘[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.
文摘Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of Côte d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding.
基金Supported by Class-A Projects of Fujian Department of Education(JA12465)Science and Technology Program of Xiamen City(3502Z20123046)
文摘Based on the chemical properties of dithiocarbamate pesticides,a device for rapid detection was developed in the paper,and the experimental conditions were optimized. Dithiocarbamate residues in fruits were successfully detected using molecular absorption spectro-photometry,and the recovery rate was over 80%.The rapid detection method was simple to operate with low cost,and was conducive to application in basic level and enterprise laboratories.
基金financially supported by the National Program for Quality and Safety Risk Assessment of Agricultural Products of China (GJFP2014002, GJFP2015002)the Core Research Budget of the Non-Profit Governmental Research Institution of China (0032014013)
文摘The presence of pesticide residues in pears is a serious health concern. This study presents the results from a 2-year investigation (2013-2014) that used gas chromatography, GS/MS and UPLC/MS-MS to measure the levels of 104 pesti- cides in 310 pear samples. In 93.2% of the samples, 43 pesticides were detected, of which the maximum residue levels (MRLs) were exceeded in 2.6% of the samples. Multiple residues (two to eight compounds) were present in 69.7% of the samples; one sample contained nine pesticides and one sample contained 10. Only 6.8% of the samples did not contain residues. To assess the health risks, the pesticide residue data have been combined with daily pear consumption data for children and adult populations. A deterministic model was used to assess the chronic and acute exposures based on the Joint Meeting on Pesticide Residues (JMPR) method. A potential acute risk was demonstrated for children in the case of bifenthrin, which was found to be present at 105.36% of the acute reference dose (ARfD) value. The long- term exposure of the Chinese consumer to pesticide residues through the consumption of raw pears was far below the acceptable daily intake (ADI) criterion. Additionally, the matrix ranking scheme was used to classify risk subgroups of pesticides and pear samples. In general, 95.5% of samples were deemed to be safe and nine pesticides were classified as being of a relatively high risk. The findings indicated that the occurrence of pesticide residues in pears should not be considered a serious public health problem. Nevertheless, a more detailed study is required for vulnerable consumer groups, especially children. Continuous monitoring of pesticides in pears and tighter regulation of pesticide residue standards are recommended.
基金supported by the Important Projec of China's Western Development (2004BA901A14)
文摘Plant pesticide residues, such as chinaberry (Melia toosendan) residue and sand cypress (Sabina vulgaris) residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with organic solvents. The only option for botanical pesticide residue utilization has been as landfill. Chinaberry residue (CBR) and sand cypress residue (SCR) were collected and composted in Yangling, Shaanxi Province, China. We studied the effects of chinaberry residue compost (CBRC), CBRC incorporated with Trichoderma viride (CBRCT), sand cypress residue compost (SCRC), and SCRC incorporated with T. viride (SCRCv) on the root-knot nematode, Meloidogyne incognita, infesting the balloonflower (Platycodon grandiflorum). Bioassay results indicated that stock solutions of the CBRCT and SCRCT extracts significantly inhibited egg hatching and caused high larval mortality, followed in degree by the CBRC and SCRC extracts. The CBR and SCR extracts caused very low inhibition of eggs and larvae. Supplementing potting mixtures with these four composts reduced the severity of root galling and increased the proportion of marketable roots. The severity of root galling decreased and the average weight of the marketable roots increased with an increase in all the composts when supplemented at rates from 5 to 30%. CBR- and SCR-supplemented pot soils also inhibited the nematodes, but CBR and SCR applied to the soil had a phytotoxic effect and inhibited balloonflower growth. Supplementing field soil with the composts reduced the severity of root galling and the populations of southern root-knot nematodes in the soil. CBRCT and SCRCT clearly enhanced the average weight of the marketable roots by 30.45 and 26.64%, respectively. Continuous supplementation with CBRCT or SCRCT in the same field significantly enhanced the control of the root-knot nematode, and the populations of nematodes continued to decrease with second inoculations. The populations of total Trichoderma spp. were distinctly enhanced and were maintained at high levels for a long time in the supplemented soils.