Preferably, RAC selections utilised in processing reports must include domain handled quantifiable residues while shut as possible towards MRL, and so that measurable residues are usually obtained, and copy reasons for the numerous ready-made commodities is usually determined. A transfer factor provides the ratio involving the particular deposit attentiveness from the refined commodity compared to that from the RAC. For model when the residue content level is actually 0.5 mg/kg throughout olives plus 0.2 mg/kg around olive oil, this airport transfer factor can be 0.2/0.5=0.4. A issue just one (= attention factor) implies a attention effect with the digesting procedures. Enhancing the residues possibly by increasing the necessary paperwork rates, shortening the actual pre-harvest time (PHI) and also spiking the RAC when using the lively factor and also it is metabolites within vitro is usually not, since along with rule, desirable. Spiking should be acceptable in the event the RAC residues might be revealed to consist merely associated with exterior residues. However, using cases, especially where by residues from the RAC are towards the analytical restriction associated with determination, domain treatment with exaggerated premiums and also shortened PHIs will be wise for getting satisfactory residue levels to the processing studies.
The first move in home and also financial food digesting is definitely your preparation associated with meal utilizing many mechanised processes, for instance taking away damaged or soiled products or aspects of crops, washing, peeling, cutting down on or perhaps hulling. This often results in significant declines in the degree of pesticide residues in the remaining edible helpings (Petersen et al., 1996; Celik et al., 1995; Schattenberg et al., 1996).
WASHING
Household cleaning treatments are ordinarily accomplished with running or perhaps standing water at small temperatures. Detergents, chlorine or ozone could be included with the particular rinse mineral water to raise the particular success from the washing machine procedure (Ong et al., 1996). If necessary, many washing machine measures may be carried out consequently.
The effects count within the physiochemical components on the pesticides, this sort of seeing that water solubility, hydrolytic rate constant, volatility along with octanol-water partition coefficient (Pow), in tandem considering the actual actual physical location in the residues; laundry operations lead in order to diminishment associated with hydrophilic residues that can be found for the exterior in the crops. In addition, the actual temps involving the particular cleaning water along with the kind of washing possesses an influence for the remains level. As stated by way of Holland et al. (1994), scorching cleanup and also the add-on regarding detergents become more efficient compared to cold waters washing. Washing along with gentle rubbing by hand within tap into normal water for just one minutes dislodges pesticide residues considerably (Barooah as well as Yein, 1996). Systemic and lipophilic pesticide residues aren't eradicated a lot through washing.
Table (1) demonstrates types of the results of washing about the remains ranges associated with diverse pesticides placed on fruits plus vegetables.
PEELING
The surface results in involving vegetables and fruits generally comprise residues regarding pesticides put on through the growing season. Therefore, peeling or shaping surgeries cut down this residues levels inside leafy vegetables. Peeling with root, tuber along with bulb vegetables which has a chef's knife can be popular loved ones practice. Many items indicate that a lot of connected with the particular residues concentration will be located inside or upon the actual peel. Peeling connected with the actual RACs could clear away greater than 50% in the pesticide residues specific to this commodity. Thus, taking away in the remove achieves just about comprehensive treatment associated with residues, consequently giving bit of inside the edible portions. This can be especially crucial for many fruits that are possibly not eaten utilizing their peels, such as bananas or even citrus fruits. Reynolds (1996) confirmed that will peeling or perhaps dropping connected with carrot minimized that residues connected with chlorfenvinphos, primiphos-methyl, quinalphos, triazophos resulting a airport transfer component of 0.2. However, this peel from the lemon from industrial peeling processes might be applied while animal give food to or for your output associated with important oils (citrus) or even pectin (citrus, apple company company etc.). For such alternative processes, it's important to appreciate which specially non-systemic floor residues will often be focused in the peel. For systemic pesticides, peeling most likely are not when effective since revealed through Sheikhorgan et al (1994). After practical application associated with thiometon upon cucumbers, simply no decrease of deposits levels could end up being detected while in the peeled cucumbers.
Under the actual Codex Alimentarius, like for example other overseas standards, MRLs consider the whole fruits, which can be correct to get accessible choices compliance together with GAP. These MRLs are of restricted significance, however, with assessing eating subjection to pesticides from fresh new fruits, that are peeled (Holland et al.,1994).
COOKING
Cooking procedures at numerous temperatures, the period from the process, as much water as well as foodstuff additives, in addition to the sort of technique (open and also closed) might have result on the residue level. Normally, residues tend to be minimized while in the particular food preparation procedure through volatilization around available systems or by hydrolysis in closed systems. In every case, incorporating cooking the liquid dilutes the residues. Several experiments were being described to the dissipation regarding pesticides with herbs while in cooking. In addition for the studies made clear throughout stand 1 the actual behaviour with the organophosphorus pesticides chlorfenvinphos, fenitrpothion, isoxathion, methidathion and prothiophos while in baking seemed to be discussed by simply Nagayama (1996) along with green tea herb leaves, spinach and also fruits. These pesticides dropped through the cooking food practice corresponding for the boiling time. According recommended to their water solubility, many pesticides were translocated with the raw materials to the baking water. On the other hand, the actual pesticide always been throughout the ready-made nutrition relating recommended to their octanol-water partition coefficient, that is a great indication associated with hydrophilic or maybe lipophilic homes from the compound. In exceptional cases, cooking food operations will cause pesticide degradation, yielding a reaction supplement associated with toxicological significance. For e.g., daminozide is degraded that will UDMH (1, 1-dimethylhydrazine), that is certainly far more efficient versus dad or mum compound (Leparulo-Lofus et al.,1992). Another example will be formation of ETU (Ethylenethiourea) through EBDCs (Ethylene bisdithiocarbamate) fungicides including mancozeb, through heating operations (Petersen et al., 1996).
Dipping within substance remedy
Sodium chloride solution is usually typically used to decontaminate the actual pesticide residues out of different fruit and veggies .there are usually many scientific tests that will demonstrate your efficaciousness regarding sodium water washing to dislodge your pesticides through crops. In this kind of process, taste associated with chopped vegetables and fruits is definitely set up your beaker made up of 5% sodium chloride solution. After 15 minutes the seed samples usually are lightly applied simply by palm with salt resolution in addition to alt mineral water can be decanted. The plus the the result with sodium solution cure to the remains concentrations of diverse pesticides utilized by vegetables have indicated throughout dining room table 1.
Kumar et al (2000) announced which dipping involving environmentally friendly chillies in 2% salt solution pertaining to 10 small as well as water to help provide effective, facilitating your removing with 32.56 in addition to 84.21% residues correspondingly at 0 plus 5 times immediately after spray associated with triazophos (700g a.i./ha) while the acephate residues were removed for you to an amount involving 78.95% at absolutely no day. Following very same approach Kumar et al (2000) observed the 90.56 and66.93% diminishment correspondingly on 0 as well as 5 times once spraying with cypermethrin inside chillies.
Dip treatment involving fruits inside NaCl solution, HCl, acetic acid, NaOH solution, potassium permanganate removed 50-60% regarding area residues connected with synthetic pyrethroids when compared to 40-50% taking away simply by hydrolytic degradation having NaOH (Awasthi, 1986b).
Water option connected with NaOH, acetic acid solution potassium dichromate and soap remedy applied as decontaminating brokers for tom ����.
The healing associated with some fruits having 2% tamarind answer dip for 5 small as well as tap water wash and also water cooking for eight min. was found to take out this residues regarding monocrotophos, carbaryl as well as fenvalerate to an level of 41.81, 100 along with 100% respectively. Treatment by using 2% salt remedy appeared to be equally effective.
Dip therapies with the brinjal fruit wioth water, sodium chloride, HCl solution, acetic acid alternative or potassium permanganate alternative ended up many located to get rid of 30-33% belonging to the residues regarding fenvalerate, permethrin, cypermethrin along with deltamethrin; NaOH resolution 40-45% in addition to Teepol (a detergent) solution 50-60%. The effect connected with washing machine within lowering the residues diminished gradually for the minute and lastly harvests.
Many studies were accomplished with all the three frequent family formulations viz. cleaning using water, salt water cleaning in addition to food preparation to help asses their particular general efficiencies with reducing the particular pesticide residues in diverse vegetables. The results happen to be made clear while in the subsequent table.
Table: Effect regarding washing, sodium drinking water cleansing in addition to preparing about pesticide residue levels.
Crop Pesticide percent associated with Residue dislodged * Result Reference
Washing with
water Salt drinking water washing Cooking
Cauliflower Methamidophos 41-48 46-47 46.94
-53.54 Largest reduction appeared to be brought about by cooking. Jacob along with Verma (1990)
Okra
Methamidophos
64-72
19-58
58-64 Washing by using drinking water could take away highest residues implying it's utmost solubility in normal water though many of the functions reduce straight down that TMRL values. Jacob in addition to Verma (1990)
Cauliflower Alpha-cypermethrin
7-38 _
12-17 Washing ended up being found to get more efficient as compared to cooking probably as a result of the actual thermal balance regarding cypermethrin. Malik et al (1997)
Cabbage
Chlorpyriphos
Quinalphos
38
41
52.13
56.50
54.3
55 With this three systems residues were reduced for some extent. They are unable to cut down that residue listed below the particular MRL. Thus your unveiled interval of the minimum of one as well as two weeks, respectively, seemed to be indicated inspite of washing preparing intended for quinalphos and also chlorpyriphos on cabbage. Nagesh along with Verma (1997)
Cow pea
Metasystox
Carbalyl
84.3
87.5
86.4
88.7
83.4
80.8 Only boiling belonging to the pod trials could detoxify your residues existing regarding outside as well as included in the structure towards the scope of safe and sound restricts by way of tenth time with treatment. Dikshit et al (1984)
Cauliflower
Malathion
60
70
80 Cooking seemed to be observed being most effective as well as lowered the TMRL value coming from 1 week to be able to zero days. Jacob along with Verma (1989)
Bhindi
Quinalphos
61.84-64.35
43-53
78-82
Both washing using water and salt waters cleaning introduced lower the actual residues below this MRL with zero days, cooking additionally does the following resulting highest reduction connected with residues.
Jacob and
Verma (1985)
Cabbage
Malathion
Carbaryl
Pyrethroids
64.60
75.40
22.06 (av.)
-
-
-
83.97
89.62
56.72 (av.)
The scope of decontamination was larger thanks to help baking as compared to cleansing for many insecticides.
Bhatia and
Verma (1994)
Leaves along with curds of cauliflower scalps involving cabbage and pods with Indian colza
Green beans
Methamidophos
DDT
Malathion
Carbaryl
65.71-77.67
71
96
52
-
-
-
-
80-88.88
52(cooked)
66 (pressure cooked)
99(cooked)
99(p.cooked)
77cooked
69(p.cooked)
Cooking dislodges greatest residues.
Water to help removed maximum DDT residues whilst preparing food works to eliminate malathion along with carbaryl residues.
Dikshit et al (1986)
Elkins et al (1968)
From the previously mentioned desk it may be stated that preparing food is actually effective to cut back your residues associated with different pesticides through various veggies although now and again laundry along with normal water had been identified to work to reduce the particular initial residues of pesticides plus it has happen to be located that while using aging with residues as well as when using the improve from the sample times around treatments your effect involving cleansing lessens to clear out that toxicant towards very same amount as that will of selections amassed immediately following bottle of spray where by cooking or cooking can be determined to be effective. One involving the possible reason for large percentage connected with removing associated with toxicant from immediately obtained biological samples since almost all of the residues are present in the floor belonging to the samples as well as for that reason it is rather effortless to take out by simply very simple cleaning while seen by means of Dikshit et al (1984,86) Elkins et al (1968), Bhatia along with Verma (1994) as well as Malik et al (1998). With time elapsed the particular residues are usually transfered into the deeper tissues or maybe strongly conform within the rough area of some vegetables. Moreover, the particular washing can not lower the particular residues towards the protected stage compared to boiling.
There are usually many scientific tests wherever many of the a few cooking systems turned out to be to be inefficient to reduce your residues listed below that MRL value. According for you to Jacob as well as Verma (1991) residues associated with quinalphos inside cared for cauliflower plants will be diminished merely for some magnitude simply by various household refinement methods like washing machine and also cooking. Nagesh plus Verma (1997) opined that the inefficiency of the home procedures pertaining to decontaminating this addressed cabbage might be due to formidable adsorption houses connected with quinalphos plus chlorpyriphos.
Effect of loved ones preparation intended for decontamination with pesticide multiresidues in profits and vegetables
Low quantities with pesticide residues had been diagnosed inside 97(40%) associated with mt 243 trials considered immediately after using normal residence washing, peeling along with cooking procedures. The number of samples containing detectable residues fallen to 47(19%) right after family members preparation. These final results specify in which remains level in most goods are considerably diminished right after household arrangement (Schattenberg et al., 1996)
Ramesh along with Balasubramanian (1999) conducted a report using vegetables and fruits compiled from Chennai neighborhood market segments and prepared by using recognised concentrations of different pesticides with decontamination examine with diverse household products like washing, baking , peeling ensuing 65-95% decontamination of pesticide residues at diverse development connected with 512 nutrition market trials analyzed, your organochlorine plus organophosphorus pesticides provide within the 12 samples were removed creating residues nicely under the actual toxicologically appropriate limits.
A brief rinse inside tap into water lowers pesticide residues about many different kinds with generate (Krol et al., 2000). Rinsing taken off residues to get nine from the twelve pesticides studied. Among captan, chlorothalonil, iprodione, vinclozolin, endosulfan, permethrin, methoxichlor, malathion, diazinon, chlorpyriphos, bifenthrin plus DDE; residues involving vinclozolin, bifenthrin plus chlorpyriphos were not removed. This analysis realises how the drinking water solubility connected with pesticides will not enjoy an important part inside the detected decrease. The majority of pesticide residues may actually are living about the surface of produce in which it's removed by the particular physical steps associated with rinsing.
Earlier experiments in the effects connected with financial and also residence getting ready with pesticide remains inside vegetables and fruit were made clear by way of Zabik (1987). The early studies exhibited deposit reduction to become substantial, having number decrease involving chlorinated hydrocarbons ranking from 50 to 99+ % for professional preparation as well as out of age 14 that will 99+ nought per cent regarding dwelling preparation with all the exception associated with parathion within spinach and also broccoli, commercvial and also residence prewparation considerably reduced organophosphate residues, when using the lessening generally finding myself that high eighty or 90% range. Carbamate residues were reduced simply by 58 to be able to 99+ % if the greens have been retail processed but only through 11 that will 92% in household preparation.
A recently available examine within Korea helps these kind of earlier experiments (Lee plus Lee, 1997). These experts discovered this 45% on the organophosphate residues have been eliminated as soon as the meals were washed with water, 56% together with detergent washing, 91% using peeling, as well as 51% having blanching or perhaps boiling.
Methods associated with multiresidue research of pesticides with fruits and vegetables
Analysis through fuel chromatography
Nakamura et al (1994) made one way for multiresidue research connected with twenty four pesticides (20 organophosphorus, 7 organochlorine, age 14 organonitrogen plus seven pyrethroid pesticides ) permitted in Japan for the groundwork regarding capillary GC following extracting the actual pesticides along with nacetone from vegetable and berries trials or with acetonitrile out of lipid that contain plants then reextraction straight into ethyl acetate (test solution). Organophosphorus pesticides were specifically based on GC-FPD. Organonitrogen pesticides were based on GC-FTD (GC-NPD) adhering to correct by simply silica carbamide peroxide gel chromatography. Organochlorine and pyrethroid pesticides ended up tested by simply GC-ECD after pick-up by florisil column chromatography. Recoveries for some vegetation at fortification concentrations involving 0.05-0.25 ppm were 42.5-128.5%. the particular recognition limits have been 0.001 ppm pertaining to organophosphorus as well as organochlorine pesticides and 0.01 ppm to get organonitrogen along with pyrethroid pesticides.
A multiresidue method was employed by Dejonckheere et al (1996) regarding willpower with organochlorine, organophosphorus plus organonitrogen pesticides throughout vegetables and fruits which were extracted with acetone followed by liquid-liquid partitioning along with water:apolar pesticides within petroleum ether phase, polar pesticides extracted from aqueous stratum having dichloromethane and also assessed simply by energy chromatography having electron capture (GC-ECD), flame photometric (GC-FPD) as well as thermoionic precise (GC-TSD) detection.
The method utilized to get multiresidue resolve connected with 52 pesticides including organophosphorus, organochlorine, organonitrogen, specific pyrethroids and dithiocarbamate pesticides in veggies as well as fruits was referred to by way of Dogheim et al (1999) employing propane chromatography. Samples were extracted with acetone taken by way of partitioning along with hexane along with dichloromethane in addition to estimated by way of GC-ECD along with GC-NPD. Dithiocarbamates were digested throughout blend of concentrated HCl, SnCl2 and mineral water for development regarding CS2 that is certainly amassed inside a good ethanolic answer connected with office assistant acetate plus diethanolamine to form a orange complex. The absorbance with yellow item has been driven spectrophotometrically with 435 nm. The typical recoveries and CVs with the 52 pesticides were 72-118 and 1-20%, respectively for the spiking degrees of 0.01-1 ppm. A similar form regarding method was likewise described simply by Kole et al (1998).
Krol et al (2000) made use of your multiresidue procedure for determination connected with 12 pesticides in vegetables and fruits when trials were taken with 2 propanol as well as petroleum ether accompanied by way of washing by using distilled drinking water three or more times. Final analysis in the examples appeared to be completed by way of GC-ECD, FPD, XSD and/or ELCD.
Ramesah and also Balasubramanian (1999) detailed a method to determine organochlorine, organonitrogen and organophosphorus pesticides throughout vegetables and fruit adhering to removal with 2-propanol and petroleum ether by hardware shaker followed by partitioning having distilled water and column washing about florisil to get OC and OP pesticides. For organonitrogen pesticides the particular extraction ended up being performed using acetone followed by partitioning with 10%NaCl and ethyl acetate and column pick up more than silica gel. organochlorine, organophosphorus in addition to organonitrogen substances ended up analyzed by simply GC-ECD,GC-FPD plus GC-NPD, respectively.
Using GC-ECD, that efficiencies connected with acetonitrile and also acetone to be able to extract the 8 pyrethroids out of a few many fruits and also vegetable selections had been as opposed by Pang et al (1997). The extraction efficacy regarding acetone has been cut-throat along with that associated with acetonitrile for any half a dozen crops as well as vegetable samples. The ruggedness tests demonstrated even more how the suggested procedure is simple, exact using beneficial precision and suitable for multiresidue evaluation of pyrethroid in several agricultural products.
Organophosphorus and also organochlorine pesticide residues from fruit and veg by way of capillary GC together with electron capture detector (ECD), nitrogen phosphorus detector (NPD), flame photometric detector (FPD) inside sulfur in addition to phosphorus modes, and also mass fast spectrometry detector (MSD) with selected ion overseeing (SIM) mode have been determined through Torres et al (1995) following extraction by Matrix Solid Phase Dispersion (MSPD) producing recoveries associated with 41-108% with general SD associated with 2-14% while in the conc. collection 0.5-10 g/liter throughout oranges, lemons, grapefruit, pears, plums, lettuces and also tomatoes.
A multiresidue technique seeing that described by way of Sannino et al (1995) intended for quantitative dedication with 39 organophosphorus chemical substances (parent pesticides as well as their particular major metabolites) with several fatty refined foods according to automatic carbamide peroxide gel permeation chromatography which has a Biobeads SX3 column plus a new methylene chloride-cyclohexane (15 + 85) eluant after extraction along with methylene chloride. Organophosphorus materials usually are quantitated simply by GC-FPD using OV-1701 in addition to DB-5 columns. Average recoveries out of trials fortified at 0.025-1 mg/kg ranged out of 50.6% for dichlorvos to help 185% pertaining to malaoxon. Determination limits were among 0.005 in addition to 0.040 mug/mL. Results were tested through gas chromatography/mass spectrometry with selected-ion monitoring.
Gas chromatographic conditions to get separation and recognition with the molecules had been selected implementing two capillary tips involving numerous polarities plus a pair of detectors, ECD plus NPD regarding multiresidue quantitative resolve regarding 37 pesticides in fruit and vegetables and also to study the proficiency of gel-permeation chromatography clean-up immediately after ethyl acetate removal (Balinova,1999).
Trova et al (1999) performed the liquid chromatographic perseverance regarding pesticide residues (including azinphos-ethyl, azinphos-methyl, carbaryl, diflubenzuron, dinocap in addition to teflubenzuron) in vegetables following extraction utilizing an ethyl acetate/n-hexane solvent program rather than the extensively employed methylene chloride. Recoveries because recommended through 'Guidelines for residues supervising inside European Union' were observed; the newest solvent process may perhaps be proved to be an alternate to halogenated compounds, dangerous for their toxicity in addition to harmful regarding their own environmental behaviors, around extraction with HPLC-determinable productive compounds.
A wide selection screening method was offered simply by Gelsomino et al (1997) for multiresidue evaluation involving 77 pesticides (12 organohalogens, 45 organonitrogens, 11 organophosphorus plus 9 pyrethroids) inside agricultural merchandise utilizing gasoline chromatography pre-loaded with long, narrow-bore fused-silica open-tubular copy along with electron-capture detector (ECD). Residues have been taken by using acetone then dichloromethane partitioning and teeth whitening gel permeation chromatographic clean up. Recoveries on the major pesticides through spiked examples of carrot, melon in addition to tomato at fortification quantities of 0.04-0.10 mg/kg had been 70-108%. Limits of recognition had been below 0.01 mg/kg to get ECD.
Beena et al (2002, 2003) accomplished supervising of vegetable biological samples using a multiresidue analytical process making use of GC-ECD and also GC-NPD programs having capillary columns.
Ueno et al (2003) analyzed a strong efficient and also trusted multiresidue way for figuring out 52 nitrogen- and/or phosphorus- containing pesticide residues within a large numbers of veggie selections by which selections ended up extracted with acetonitrile, plus the divided acetonitrile coating had been pure simply by gel permeation chromatography that torn the pesticide eluate into only two fractoions, the pesticide fractions were respectively pure by some sort of 2-step minicolumn cleanup, the other fraction through silica gel minicolumn; primary little bit by way of that tandem minicolumn (florisil minicolumn, injected with silica gel minicolumn) which often was eluted along with acetone-petroleum ether (3+7). The put together eluate seemed to be suffering from combined column petrol chromatography having nitrogen-phosphorus and relationship photometric detection. Recoveries connected with 52 pesticides from prepared biological samples ranged from seventy two to help 108% using family member typical deviations involving 2-17%, except the recoveries of methamidophos along with chorothalonil. The recognition limits in the pesticides were being satisfactory (0.001-0.009 mg/kg) to get monitoring of pesticide residues within vegetables.
Menkissoglu et al (2004) conducted a study from the matrix induced consequence pertaining to 16 common pesticides, normally within monitoring reports with tomato pepper along with cucumber, by using a very simple multiresidue method along with GC-ECD or NPD, without a preceding cleaning step. Anomalously large GC responses along with consequently quite high recoveries for a lot of pesticides in the extracts ended up purchased by the regular calibration together with pesticide option in ethyl acetate.
A faster, a smaller amount effective, environmentally less dangerous supercritical smooth removal (SFE) process appeared to be considered by Garcia et al (1996) above regular sonvent extraction methods that extraction involving imidacloprid, methiocarb, chlorpyrifos, chlorothalonil, endosulfan-1, endosulfan-2 along with endosulfan sulfate, out of pepper along with tomato applying vegetable sample: anhydrous magnesium sulfate (5:7) mixtures for you to carryout this extraction with supercritical CO2 along with HPLC/DAD,GC/ECD as well as GC/FPD intended for analysis. The chosen SFE circumstances have been three hundred atm, 500C, 200?l associated with methanol static modifier, 1 instant static time, in addition to dynamic removal having 15 ml involving CO2 plus collection with a few ml of ethyl acetate. Except pertaining to imidacloprid, that was not recovered within any kind of from the applied conditions, pesticide recoveries were higher than 80%.
A simplified approach will be described simply by Chaput (1987) when slow phase fruit juice chromatography seemed to be utilised by using post column derivatisation and also fluorescence detector to find out seven N-methyl carbamates (aldicarb, carbaryl, carbofuran, methiocarb, methomyl, oxamyl and propoxur) in addition to three or more related metabolites inside vegetables and fruits right after extraction in the sample with methanol as well as carbamide peroxide gel permeation chromatography (GPC) or perhaps GPC with on-line Nuclear-celite correct intended for crops having excessive chlorophyll and/or carotene content (e.g. cabbage and broccoli). Recovery information were obtained by means of fortifying your five numerous sprouts (apples, broccoli, cabbage, cauliflower in addition to potatoes) at 0.05 along with 0.5 ppm. Recoveries averaged 93% at equally fortification levels. The coefficient of variance with the process at both equally levels can be 
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