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1.
The supervised field trials were conducted in a commercial apple orchard in 2016. The trials were an attempt to determine a model for dissipation and toxicological evaluation of fluopyram, tebuconazole, captan, tetrahydrophthalimide (THPI), pirimicarb, spirodiclofen, and boscalid residues detected in fruit of Red Jonaprince, Lobo, and Gala varieties immediately before harvest. The analysis also covered amounts of pesticides still present in remnants of calyx in Lobo and Gala varieties immediately before harvest. Laboratory samples of ripe apples were collected within 14 days of the treatment. Levels of pesticide residues detected in the samples changed at a constant exponential rate, and the residue levels found in ripe apples of Red Jonaprince, Gala, and Lobo varieties immediately before harvest were below maximum residue levels (MRL). Overall, captan residues in remnants of calyx were at a level of 22.3% for the Gala variety and 9.3% for the Lobo variety. Likewise, the long-term daily intake of the detected substances by a Polish adult consumer was low, ranging from 0.02% ADI for pirimicarb to 0.72% ADI for captan.  相似文献   

2.
Pesticides are considered as the most polluting substances. The residue of pesticides in agricultural crops, especially in greenhouse harvests, has been reported critical. Cucumber, considered as a vegetable, is an agricultural product which is commonly found in the Iranian food basket. The current study aims to assess the level of diazinon and oxydemeton-methyl existing in cucumbers sampled from Kerman greenhouses. The pesticide residue was extracted by acetone and dichloromethane. The extracts were cleaned up according to the solid-phase extraction method. The pesticide residues were then determined by capillary gas chromatography with nitrogen-phosphorus detection. The recoveries were 83 and 85 %, the limit of detection was 0.028 and 0.034 mg/kg, and the limits of qualification were 0.093 and 0.113 mg/kg for diazinon and oxydemeton-methyl in cucumber samples, respectively. The median of diazinon residue was detected 0.582 mg/kg, which was 11.64 times the national maximum residue limit (MRL) (0.05 mg/kg), and the median for oxydemeton-methyl was 1.910 mg/kg, being 1.91 times the MRL (1 mg/kg).  相似文献   

3.
Pesticide residues in vegetable samples from the Andaman Islands, India   总被引:2,自引:0,他引:2  
Vegetable samples of brinjal, okra, green chilli, crucifers, and cucurbits collected from farmers' field were tested for the presence of organochlorine (OC), organophosphorus (OP), and synthetic pyrethroid (SP) compounds using a gas chromatograph equipped with electron capture and flame thermionic detectors. Of the samples tested, 34.0 % were found to have pesticide residues. Among the OC compounds, α-endosulfan, β-endosulfan, and endosulfan sulfate were detected in 14.5 % of the samples with residues. These were taken from crucifer, okra, green chilli, and cucurbit samples. SP compound residues, such as α-cypermethrin, fenvalerate I, fluvalinate I, deltamethrin, and λ-cyhalothrin were detected in 32 % of the samples with residues. OP compound residues such as chlorpyrifos, profenofos, monocrotophos, triazophos, ethion, dimethoate, and acephate were found in 54 % of the samples with residues, which were taken from all vegetable samples. Of the positive samples, 15.3 % were found to contain residues exceeding the prescribed maximum residue limit. The average pesticide residue content across all the vegetable samples was 0.108 ppm, with values ranging from 0.008 to 2.099 ppm. Multiple residues of more than one compound were detected in 34.1 % of samples containing residues.  相似文献   

4.
In this study, 226 samples of seven types of domestic vegetables collected from several vegetable-growing regions in Hebei Province of China were tested for the presence of 38 different agricultural pesticides using a gas chromatograph equipped with electron capture and nitrogen phosphorus detectors. The aim of this study was to investigate the distribution of pesticides in main vegetables from Hebei Province. Results showed that, in 65.93 % of the samples, no residues were found, 31.42 % of the samples contained pesticide residues at or below the maximum residue levels (MRLs), and 2.65 % of the samples contained pesticide residues above MRL. The most frequently detected pesticides were acephate (31), followed by cyhalothrin (15), bifenthrin (8), omethoate (6), isazophos (6), dimethoate (5), chlorpyrifos (2), and malathion (1). Some (1.33 %) of the samples contained multiple residues. The results provide useful information on the current contamination status of a key agricultural area in North China, and points to the continuous monitoring and strict regulation of pesticide use on vegetables are necessary.  相似文献   

5.
The dynamic and residues of florasulam and flumetsulam in corn field ecosystem were investigated using quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of quantification (LOQs) of the proposed method ranged from 0.005 to 0.01 mg/kg. Mean recoveries and relative standard deviations (RSDs) of the two compounds in all samples at three spiking levels ranged 94–110 % and 2.0–9.2 %, respectively. Florasulam and flumetsulam degradation followed first-order kinetics with half-lives 1.7–2.9 and 3.3–8.7 days in soil and 1.3–1.8 and 0.9–1.7 days in plant, respectively. The residues in all the samples were found to be less than the LOQs at preharvest intervals of 53 and 78 days. The results suggest that the combined use of florasulam and flumetsulam on corn is considered to be safe under the recommended conditions and can be utilized for establishing the maximum residue limit (MRL) of florasulam in corn in China.  相似文献   

6.
Prediction of residual concentrations of applied pesticides during the pre-harvest period may be required to ensure the safety of agricultural products. In this study, time-dependent dissipation trends of carbaryl (CB), kresoxim-methyl (KM), flubendiamide (FB), flufenoxuron (FN), bitertanol (BT), and chlorantraniliprole (CN) applied to apples at recommended and threefold greater doses were modeled to estimate pre-harvest residue limit concentrations (CPHRL) indicating permissible pesticide concentrations during the pre-harvest period. Double-exponential (DE) model results best fit the dissipation trends of all tested pesticides (correlation coefficients of 0.91–0.99) compared to zero-, first-, and second-order models. Among the pesticides examined, CB half-lives in apples of 2.9 and 6.6 days were the shortest, while those of FN (21.1–32.7 days) were the longest. The CPHRL values for each pesticide in apples were estimated with DE model parameter values and could be used to determine harvest dates for safe apples with pesticide concentrations below their maximum residue limits. Application of the DE model for CPHRL calculation provides more accurate information for farmers to produce agricultural products safe from pesticide residues.  相似文献   

7.
Animal products like milk and meat are often found to be contaminated with residues of persistent pesticides and other toxic substances. The major source of entry of these compounds to animal body is the contaminated feed and fodder. So, unless the residues are managed at this stage, it is very difficult to prevent contamination in milk and meat. Therefore, the status of residue level of most persistent organochlorinated pesticides (OCP) in feed and fodder should be monitored regularly. The frequency of occurrence and contamination levels of OCP residues in different kinds of animal concentrate feed and straw samples collected from Bundelkhand region of India were determined. Out of 533 total samples, 301 i.e. 56.47% samples were positive containing residues of different OCPs like hexachlorocyclohexane (HCH) isomers, dichlorodiphenyltrichloroethane (DDT) complex, endosulfan and dicofol. Among different HCH isomers, the mean concentration of ??-HCH was highest, and total HCH varied from 0.01 to 0.306 mg kg???1. In case of DDT complex, i.e. DDD, DDE and DDT, the concentration ranged between 0.016 and 0.118 mg kg???1 and the pp| isomers were more frequently encountered than their op| counterparts. Endosulfan was also found in some samples in concentration ranging from 0.009 to 0.237 mg/kg, but dicofol could be recorded in very few samples. Although feed samples were found to contain OC residues, after comparing their levels in positive samples with the limiting values of respective pesticides, only very few were found to exceed the threshold level. Otherwise, they were mostly within safe limits.  相似文献   

8.
The dissipation and residues of bispyribac-sodium in rice cropping system were studied. Bispyribac-sodium residues were extracted by a simple analytical method based on QuEChERs and detected by LC-MS/MS. The limit of detection for bispyribac-sodium of this method was 0.375?×?10?3 ng. The limit of quantification (LOQ) was 5.0 μg/kg for rice plant samples, 2.0 μg/kg for rice hull, 0.2 μg/kg for water, and 0.1 μg/kg for soil and husked rice samples. The average recoveries of bispyribac-sodium ranged from 74.7 to 108 %, with relative standard deviations less than 13 %. The half-lives of bispyribac-sodium in rice plant, water, and soil were in the range of 1.4–5.6 days. More than 90 % of bispyribac-sodium residue dissipated within 5 days. The final residues of bispyribac-sodium in rice were all below LOQ at harvest time.  相似文献   

9.
Two multiresidue methods were developed to determine pesticides in air collected in California. Pesticides were trapped using XAD-4 resin and extracted with ethyl acetate. Based on an analytical method from the University of California Davis Trace Analytical Laboratory, pesticides were detected by analyzing the extract by gas chromatography–mass spectrometry (GC-MS) to determine chlorothalonil, chlorthal-dimethyl, cycloate, dicloran, dicofol, EPTC, ethalfluralin, iprodione, mefenoxam, metolachlor, PCNB, permethrin, pronamide, simazine, trifluralin, and vinclozolin. A GC with a flame photometric detector was used to determine chlorpyrifos, chlorpyrifos oxon, diazinon, diazinon oxon, dimethoate, dimethoate oxon, fonophos, fonophos oxon, malathion, malathion oxon, naled, and oxydemeton. Trapping efficiencies ranged from 78 to 92 % for low level (0.5 μg) and 37–104 % for high level (50 and 100 μg) recoveries. Little to no degradation of compounds occurred over 31 days; recoveries ranged from 78 to 113 %. In the California Department of Food and Agriculture (CDFA) method, pesticides were detected by analyzing the extract by GC-MS to determine chlorothalonil, chlorpyrifos, cypermethrin, dichlorvos, dicofol, endosulfan 1, endosulfan sulfate, oxyfluorfen, permethrin, propargite, and trifluralin. A liquid chromatograph coupled to a MS was used to determine azinphos-methyl, chloropyrifos oxon, DEF, diazinon, diazinon oxon, dimethoate, dimethoate oxon, diuron, EPTC, malathion, malathion oxon, metolachlor, molinate, norflurazon, oryzalin, phosmet, propanil, simazine and thiobencarb. Trapping efficiencies for compounds determined by the CDFA method ranged from 10 to 113, 22 to 114, and 56 to 132 % for 10, 5, and 2 μg spikes, respectively. Storage tests yielded 70–170 % recovery for up to 28 days. These multiresidue methods represent flexible, sensitive, accurate, and cost-effective ways to determine residues of various pesticides in ambient air.  相似文献   

10.
A modified LC-MS method for the analysis of mepiquat residue in wheat, potato, and soil was developed and validated. A hydrophilic interaction liquid chromatographic column has been successfully used to retain and separate the mepiquat. Mepiquat residue dynamics and final residues in supervised field trials at Good Agricultural Practice (GAP) conditions in wheat, potato, and soil were studied. The limits of quantification for mepiquat in all samples were all 0.007 mg kg?1, which were lower than their maximum residue limits. At fortification levels of 0.04, 0.2, and 2 mg kg?1 in all samples, recoveries ranged from 77.5 to 116.4 % with relative standard deviations of 0.4–7.9 % (n?=?5). The dissipation half-lives (T 1/2) of mepiquat in soil (wheat), wheat plants, soil (potato), and potato plants were 4.5–6.3, 3.0–5.6, 2.2–4.6, and 2.4–3.2 days, respectively. The final residues of mepiquat were below 0.153 mg kg?1 in soil (wheat), 0.052–1.900 mg kg?1 in wheat, below 0.072 mg kg?1 in soil (potato), and below 1.173 mg kg?1 in potato at harvest time. Moreover, pesticide risk assessment for all the detected residues was conducted. A maximum 0.0012 % of acceptable daily intake (150 mg kg?1) for national estimated daily intake indicated low dietary risk of these products.  相似文献   

11.
A field dissipation study was conducted to evaluate the pre-harvest interval (PHI) and processing factor (PF) for kresoxim methyl (Ergon 44.3 SC) residues in grapes and during raisin making process at recommended dose (RD) and double the recommended dose (DRD). Kresoxim methyl residues dissipated following 1st-order kinetics with a half-life of 10 and 18 days at RD and DRD, respectively. The PHIs with respect to the European Union maximum residue limit (EU-MRL) of 1 mg kg?1 for grapes were 13 and 30 days at RD and DRD, respectively. The degradation data during grape to raisin making process were best fitted to nonlinear 1st?+?1st-order kinetics with a half-life ranging between 4 and 8 days for both shade drying and with raisin dryer at different doses. The PFs were 1.19 and 1.24 with shade drying and 1.09 and 1.10 with raisin dryer, respectively, which indicates concentration of the residues during raisin making process. The dietary exposure of kresoxim methyl on each sampling day was less than the respective maximum permissible intake both at RD and DRD. The residues of kresoxim methyl in market samples of grapes and raisins were well below the EU-MRL and were also devoid of any risk of acute toxicity related to dietary exposure.  相似文献   

12.
Dissipation behavior, final residue, and risk assessment of butralin in soybean, green soybean, plant, and soil were investigated. Butralin residues were extracted with acetonitrile and then soybean samples were detected with gas chromatography-mass spectrometer (GC-MS) and soil samples were determined with GC with nitrogen phosphorous detector (GC-NPD). The limit of quantification (LOQ) of the method was 0.01 mg/kg for soybean, green soybean, plant, and soil. Average recoveries ranged from 90.4 ~ 98.2% for green soybean, 86.2 ~ 86.6% for soybean, 86.0 ~ 98.8% for plant, and 85.0 ~ 106.8% for soil. The relative standard deviations (RSDs) were 2.0 ~ 7.2% for green soybean, 2.0 ~ 3.0% for soybean, 3.1 ~ 8.1% for plant, and 1.8 ~ 6.6% for soil. Half-lives of butralin in soil samples varied in the range of 11–22 days. At harvest time, final residues of butralin in soybean and green soybean were lower than LOQ. Risk assessment demonstrated that, at recommended dosage and frequency, butralin would not induce significant harm on humans. The study could be used as a quantitative basis for application of butralin on soybean.  相似文献   

13.
Persistence behavior of insecticides chlorpyriphos, profenofos, triazophos, cypermethrin, and deltamethrin following the use of three combination formulations Action 505 (chlorpyriphos?+?cypermethrin), Roket 44EC (profenofos?+?cypermethrin), and Anaconda Plus (triazophos?+?deltamethrin) was studied in cabbage following the spray application at the recommended and double doses. Bio-efficacy of these formulations was also evaluated against mustard aphids (Lipaphis erysimi Kaltenbach) and diamondback moth (Plutella xylostella L.). The residues of different insecticides persisted for 5–8 days at low dose and 8–12 days at high dose. The residues dissipated with time and 87–100 % dissipation was recorded on the 8th day. The half-life values varied from 0.4 to 1.6 days. Based on the acceptable daily intake (ADI) values, a safe waiting period of 1 day has been suggested for the formulations Action 505 and Roket 44EC and 3 days for Anaconda Plus at the recommended dose of application. Action (1.6 L/ha) treatment was found to be the best as it significantly reduced the diamondback moth (DBM) (~60 %) and aphid population (~70 %) besides giving the highest yield (170 % increase over control).  相似文献   

14.
Agricultural pesticides are widely used in Suriname, an upper middle-income Caribbean country located in South America. Suriname imported 1.8 million kg of agricultural pesticides in 2015. So far, however, national monitoring of pesticides in crops is absent. Reports from the Netherlands on imported Surinamese produce from 2010 to 2015 consistently showed that samples exceeded plant-specific pesticide maximum residue limits (MRLs) of the European Union (EU). Consumption of produce containing unsafe levels of pesticide residues can cause neurological disorders, and particularly, pregnant women and children may be vulnerable. This pilot study assessed the presence of pesticide residues in commonly consumed produce items cultivated in Suriname. Thirty-two insecticides (organophosphates, organochlorines, carbamates, and pyrethroids) and 12 fungicides were evaluated for their levels in nine types of produce. Pesticide residue levels exceeding MRLs in this study regarded cypermethrin (0.32 μg/g) in tomatoes (USA MRL 0.20 μg/g), lambda-cyhalothrin (1.08 μg/g) in Chinese cabbage (USA MRL 0.40 μg/g), endosulfan (0.07 μg/g) in tannia (EU MRL 0.05 μg/g), and lindane (0.02 and 0.03 μg/g, respectively) in tannia (EU MRL 0.01 μg/g). While only a few pesticide residues were detected in this small pilot study, these residues included two widely banned pesticides (endosulfan and lindane). There is a need to address environmental policy gaps. A more comprehensive sampling and analysis of produce from Suriname is warranted to better understand the scope of the problem. Preliminary assessments, using intake rate, hazard quotient, and level of concern showed that it is unlikely that daily consumption of tannia leads to adverse health effects.  相似文献   

15.
Assessment of levels of pesticide residues in vegetables was carried out in some villages in the Western Usambara and Uluguru Mountains of Tanzania where varieties of vegetables are grown. Tomatoes and cabbages were the most popular enterprise grown all year round and therefore were selected as the model crops for this study. Analysis of the cleaned sample extracts on a gas chromatography with electron capture detector (GC-ECD) and confirmation on the Gas chromatography–mass spectrometry (GC-MS) revealed dominance of organochlorine pesticides. Organophosphorous pesticides (parathion and marathion) were only detected in some samples, however, in most cases with higher concentrations compared to organochlorine pesticides. Levels of pesticide residues detected in vegetables were up to: parathion 5.07 μg/Kg, marathion 3.73 μg/Kg, α-endosulfan 0.32 μg/Kg, β-endosulfan 0.53 μg/Kg, dieldrin 1.36 μg/Kg, γ-HCH 0.25 μg/Kg, α-HCH 0.09 μg/Kg, and p, p′-DDT 0.64 μg/Kg. These results clearly show that vegetables are contaminated with different pesticide residues. However, the total levels of pesticide residues in both tomatoes and cabbages are lower than their respective codex alimentarius maximum residue levels (MRLs). This means that the vegetables produced in the area are suitable for human consumption.  相似文献   

16.
Quizalofop ethyl, a phenoxy propionate herbicide, is used for postemergence control of annual and perennial grass weeds in broad-leaved crops in India. The experiments were designed to study the dissipation kinetics of quizalofop ethyl on onion for two seasons. A simple, rapid, and sensitive method for estimation of quizalofop ethyl residues in onion and soil was developed and validated. The recoveries of quizalofop ethyl residues from onion and soil at different spiking level range from 84.81 to 92.68 %. The limit of quantification of this method was found to be 0.01 μg g?1. The risk assessment through consumption of the onion in comparison to its acceptable daily intake which is an important parameter for the safety of the consumer was also evaluated. Standardized methodology supported by recovery studies was adopted to estimate residues of quizalofop ethyl on onion and soil. The average initial deposits of quizalofop ethyl on onion were observed to be 0.25 and 0.33 mg kg?1, following single application of the herbicide at 50 g active ingredient (a.i.) ha?1 during 2009 and 2010, respectively. The half-life values (T 1/2) of quizalofop ethyl on onion crop were worked out to be 0.85 and 0.79 days, respectively, during 2009 and 2010. At harvest time, the residues of quizalofop ethyl on onion and soil were found to be below the determination limit of 0.01 mg kg?1 following single application of the herbicide at 50 and 100 g a.i. ha?1 for both the periods.  相似文献   

17.
Ozonated water dip technique was evaluated for the detoxification of six pesticides, i.e., chlorpyrifos, cypermethrin, azoxystrobin, hexaconazole, methyl parathion, and chlorothalonil from apple fruits. Results revealed that ozonation was better than washing alone. Ozonation for 15 min decreased residues of the test pesticides in the range of from 26.91 to 73.58%, while ozonation for 30 min could remove the pesticide residues by 39.39–95.14 % compared to 19.05–72.80 % by washing. Cypermethrin was the least removed pesticide by washing as well as by ozonation. Chlorothalonil, chlorpyrifos, and azoxystrobin were removed up to 71.45–95.14 % in a 30-min ozonation period. In case of methyl parathion removal, no extra advantage could be obtained by ozonation. The HPLC analysis indicated that ozonation also affected adversely the ascorbic acid and cyanidin-3-glucoside content of apples. However, 11 polyphenols studied showed a mixed trend. Gallic acid, 3,4-dihydroxybenzoic acid, catechin, epicatechin, p-coumaric acid, quercetin-3-O-glucoside, quercetin, and kaempferol were found to decrease while syringic acid, rutin, and resveratrol were found to increase in 30-min ozonation.  相似文献   

18.
Pesticide residue analysis of soil,water, and grain of IPM basmati rice   总被引:1,自引:0,他引:1  
The main aim of the present investigations was to compare the pesticide load in integrated pest management (IPM) with non-IPM crops of rice fields. The harvest samples of Basmati rice grain, soil, and irrigation water, from IPM and non-IPM field trials, at villages in northern India, were analyzed using multi-pesticide residue method. The field experiments were conducted for three consecutive years (2008–2011) for the successful validation of the modules, synthesized for Basmati rice, at these locations. Residues of tricyclazole, propiconazole, hexconazole, lambda cyhalothrin, pretilachlor chlorpyrifos, DDVP, carbendazim, and imidacloprid were analyzed from two locations, Dudhli village of Dehradun, Uttrakhand and Saboli and Aterna village of Sonepat, Haryana. The pesticide residues were observed below detectable limit (BDL) (<0.001–0.05 μg/g) in all 24 samples of rice grains and soil under IPM and non-IPM trials. Residues were below detection level (<0.001–0.05 μg/L) in irrigation water samples (2008–09). Residues of tricyclazole and carbendazim, analyzed from same locations, revealed pesticide residues as BDL (<0.001–0.05 μg/g) in all 40 samples of Basmati rice grains and soil. It was also observed as BDL (<0.001–0.05 μg/L) for 12 water samples (2009–2010). The residues of tricyclazole, propioconazole, chlorpyrifos, hexaconazole, pretilachlor, and λ-cyhalothrin were also found as BDL (<0.001–0.05 μg/g) in 40 samples of Basmati rice grains and soil and 12 water samples (<0.001–0.05 μg/L) (2010–2011).  相似文献   

19.
The dissipation, residues, and risks of 2,4-dicholrophenoxyacetic acid (2,4-d) in citrus under field condition were investigated based on a simple ultra-performance LC (UPLC)-MS/MS method. The results indicated that the residue level of 2,4-d in citrus did not degrade gradually with sampling time under field condition. At pre-harvest intervals (PHI) of 20–40 days, 2,4-d residues were 0.021–0.269 mg/kg in citrus flesh, 0.028–0.337 mg/kg in whole citrus, and 0.028–0.376 mg/kg in citrus peel, all bellow the China maximum residue limit in citrus (1 mg/kg). Risks of 2,4-d were assessed by calculation of risk quotient, and the results revealed no significant health risks after consumption of citrus.  相似文献   

20.
Chlorantraniliprole, an anthranilic diamide insecticide with novel mode of action is found effective against several lepidopteran as well as coleopteran, dipteran, and hemipteran pests. The present studies were carried out to study the dissipation pattern of chlorantraniliprole on cauliflower and to suggest suitable waiting period for the safety of consumers. Quick, easy, cheap, effective, rugged, and safe method was used for the extraction and cleanup of samples and the residues of chlorantraniliprole were estimated using high-performance liquid chromatograph (HPLC) and confirmed by liquid chromatograph–mass spectrometer and high-performance thin layer chromatograph. Following three applications of chlorantraniliprole (Coragen 18.5 SC) at recommended dose (9.25 g a.i.?ha?1) and double the recommended dose (18.50 g a.i.?ha?1), the average initial deposits of chlorantraniliprole were observed to be 0.18 and 0.29 mg kg?1, respectively. These deposits were found to be less than the maximum residue limit of 2.0 mg kg?1 prescribed by the Codex Alimentarius Commission. These residues dissipated below the limit of quantification of 0.10 mg kg?1 after 3 and 5 days at recommended and double the recommended dosages, respectively. The half-life value (T 1/2) of chlorantraniliprole was worked out to be 1.36 days following its application at recommended dosages. Hence, the use of this pesticide at recommended dosages does not seem to pose any risk, and a waiting period of 1 day is suggested for safe consumption of cauliflower curds.  相似文献   

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