Tuesday, August 30, 2011

Purification of Pesticide Remains on Vegetables and fruit

Preferably, RAC selections utilised in refinement studies ought to consist of field addressed quantifiable residues seeing that shut as they can for the MRL, to ensure measurable residues will be obtained, along with transfer elements for that different delt with goods is usually determined. A move component provides the percentage of the deposits attention from the processed commodity to that particular inside the RAC. For model should the deposit awareness will be 0.5 mg/kg in olives and 0.2 mg/kg around olive oil, the transfer issue is 0.2/0.5=0.4. A aspect just one (= concentration factor) suggests your attention influence associated with the digesting procedures. Enhancing your residues sometimes by improving the necessary paperwork rates, shortening this pre-harvest time period (PHI) or maybe spiking that RAC when using the lively compound and it has the metabolites inside vitro is not, as and rule, desirable. Spiking is just suitable if the RAC residues can certainl y be shown to consist only of area residues. However, some cases, specifically where residues within the RAC are near to the analytical restrict connected with determination, area treatment with exaggerated premiums or reduced PHIs will be a good idea to help receive sufficient deposit quantities for the canning studies.

The initial phase inside home or business food refinement is a preparing regarding meals implementing a variety of hardware processes, this kind of when deleting damaged or even soiled items or portions of crops, washing, peeling, trimming or even hulling. This usually ends up in important declines inside level of pesticide residues within the remaining edible a percentage (Petersen et al., 1996; Celik et al., 1995; Schattenberg et al., 1996).

WASHING

Household cleansing methods are usually accomplished using jogging or maybe standing waters at reasonable temperatures. Detergents, chlorine or ozone is usually included with your to help drinking water to boost the particular results on the cleaning system (Ong et al., 1996). If necessary, many washing guidelines might be conducted consequently.

The outcomes be based upon the physiochemical components on the pesticides, just like normal water solubility, hydrolytic quote constant, volatility and octanol-water partition coefficient (Pow), with the particular physical place on the residues; washing techniques produce decline of hydrophilic residues that happen to be found on the particular surface on the crops. In addition, your temps of the washing water as well as the kind of washing includes a good impact to the deposit level. As directed out by Holland et al. (1994), hot cleanup as well as the inclusion of detergents become more successful as compared with cool normal water washing. Washing in conjunction with delicate massaging by hand within faucet water intended for just one min dislodges pesticide residues a lot (Barooah and Yein, 1996). Systemic along with lipophilic pesticide residues are certainly not taken away drastically by washing.

Table (1) exhibits and also the the effects associated with laundry about the residue levels associated with diverse pesticides applied to fruits and also vegetables.

PEELING

The external finds associated with produce often consist of residues with pesticides used in the developing season. Therefore, peeling or lowering procedures lower the particular residues ranges throughout leafy vegetables. Peeling of root, tuber in addition to light fruit and vegetables having a dagger is actually prevalent family practice. Many good examples exhibit that most belonging to the residues concentration is located within and also on the peel. Peeling regarding the actual RACs may perhaps take out over 50% in the pesticide residues contained in your commodity. Thus, removal from the peel from the lemon achieves pretty much finished removing of residues, thus leaving little inside edible portions. This will be in particular necessary pertaining to profits which have been certainly not eaten making use of their peels, for example bananas or citrus fruits. Reynolds (1996) showed which peeling or maybe lowering of carrot decreased the residues with chlorfenvinphos, p rimiphos-methyl, quinalphos, triazophos resulting a new transfer aspect associated with 0.2. However, the actual peel from the lemon coming from commercial peeling systems work extremely well since animal supply or for your generation with vital oils (citrus) and also pectin (citrus, apple company company etc.). For this kind of conventional processes, it will be important to appreciate of which especially non-systemic surface residues can be centered from the peel. For systemic pesticides, peeling probably are not since effective while found by Sheikhorgan et al (1994). After program of thiometon about cucumbers, no decrease of residue levels may very well be recognized from the peeled cucumbers.

Under this Codex Alimentarius, as inside different global standards, MRLs relate to the whole fruits, that is certainly correct to get evaluating complying having GAP. These MRLs will be of constrained significance, however, throughout examining diet vulnerability that will pesticides from fresh fruits, which can be peeled (Holland et al.,1994).

COOKING

Cooking procedures at different temperatures, the particular time-span with the process, the amount of drinking water or maybe meal additives, as well as the form of technique (open and also closed) sometimes have a direct impact on your residue level. Normally, residues will be decreased over the food preparation method by volatilization in start programs or even by hydrolysis throughout sealed systems. In almost any case, introducing cooking fluid dilutes this residues. Several studies have been described for the dissipation with pesticides in sprouts while in cooking. In improvement towards reports summarized within kitchen table 1 the particular habits from the organophosphorus pesticides chlorfenvinphos, fenitrpothion, isoxathion, methidathion as well as prothiophos throughout cooking has been examined simply by Nagayama (1996) with natural tea leaves, spinach along with fruits. These pesticides diminished over the preparing food procedure related for the cooking time. A ccording to their waters solubility, many pesticides were translocated in the uncooked materials in to the cooking food water. On one other hand, the actual pesticide continued to be from the processed meals in accordance with their particular octanol-water partition coefficient, which can be a great indicator with hydrophilic and also lipophilic homes belonging to the compound. In exceptional cases, preparing food processes might cause pesticide degradation, yielding a outcome item involving toxicological significance. For e.g., daminozide can be degraded to UDMH (1, 1-dimethylhydrazine), that is certainly a lot more potent versus parent compound (Leparulo-Lofus et al.,1992). Another example will be formation of ETU (Ethylenethiourea) from EBDCs (Ethylene bisdithiocarbamate) fungicides for instance mancozeb, throughout warming up processes (Petersen et al., 1996).

Dipping throughout compound alternative

Sodium chloride option would be generally employed to decontaminate the actual pesticide residues from various vegatables and fruits .there tend to be several scientific studies to help prove this efficiency involving sodium normal water cleansing for you to dislodge that pesticides through crops. In this particular process, small sample with chopped fruits and vegetables can be set up a beaker containing 5% sodium chloride solution. After 15 minutes the grow crops samples tend to be slowly rubbed by hand inside salt answer plus alt water can be decanted. The and also the the consequence associated with sodium remedy treatment for the residue degrees of diverse pesticides given to vegetables happen to be found within table 1.

Kumar et al (2000) reported this dipping regarding natural chillies inside 2% sodium resolution regarding 10 moment then water wash provide effective, aiding the taking away regarding 32.56 and also 84.21% residues correspondingly with 0 and some days to weeks after apply involving triazophos (700g a.i./ha) insurance policy coverage acephate residues were taken off to a good scope of 78.95% at absolutely no day. Following exact technique Kumar et al (2000) witnessed your 90.56 and66.93% decline correspondingly with 0 plus some days soon after spraying involving cypermethrin around chillies.

Dip treatment of fruits in NaCl solution, HCl, acetic acid, NaOH solution, potassium permanganate taken out 50-60% involving surface residues of fabricated pyrethroids compared to 40-50% removing simply by hydrolytic degradation using NaOH (Awasthi, 1986b).

Water answer of NaOH, acetic acid potassium dichromate along with soap resolution employed when decontaminating agents for tom ����.

The therapy regarding some fruits using 2% tamarind alternative dip pertaining to five tiny then engage waters wash in addition to heavy steam preparing regarding eight min. had been discovered to get rid of the residues of monocrotophos, carbaryl as well as fenvalerate to be able to a great degree with 41.81, hundred plus 100% respectively. Treatment by using 2% sodium solution had been just as effective.

Dip treatments of the brinjal fresh fruit wioth water, salt chloride, HCl solution, acetic plaque created by sugar option and also potassium permanganate solution ended up most identified for you to get rid of 30-33% regarding the actual residues of fenvalerate, permethrin, cypermethrin in addition to deltamethrin; NaOH option 40-45% and Teepol (a detergent) solution 50-60%. The result of washing around decreasing the residues decreased progressively for the second as well as finally harvests.

Many studies were being carried out considering the three typical household products viz. cleanup along with water, salt mineral water laundry in addition to food preparation for you to asses his or her distant relative efficiencies around reducing your pesticide residues throughout different vegetables. The results are already summarized while in the subsequent table.



Table: Effect associated with washing, sodium drinking water washing machine in addition to cooking upon pesticide residue levels.

Crop Pesticide per cent connected with Residue dislodged * Result Reference

Washing with

water Salt normal water washing Cooking

Cauliflower Methamidophos 41-48 46-47 46.94

-53.54 Largest lowering was brought about by cooking. Jacob and Verma (1990)

Okra

Methamidophos

64-72

19-58

58-64 Washing together with water could possibly remove highest possible residues showing it has the greatest solubility in water even though many of the operations reduce down the TMRL values. Jacob and Verma (1990)

Cauliflower Alpha-cypermethrin

7-38 _

12-17 Washing appeared to be found for you to often be better when compared with preparing probably with the energy firmness of cypermethrin. Malik et al (1997)

Cabbage

Chlorpyriphos

Quinalphos

38

41

52.13

56.50

54.3

55 With that about three processes residues were reduced to some extent. They can not lower the deposit under this MRL. Thus a unveiled time period of an minimum of a single as well as two weeks, respectively, ended up being advised regardless of laundry food preparation for quinalphos and also chlorpyriphos about cabbage. Nagesh and also Verma (1997)

Cow pea

Metasystox

Carbalyl

84.3

87.5

86.4

88.7

83.4

80.8 Only boiling of the pod examples could decontaminate the residues existing with floor as well as included in the tissue for the scope involving safe limits through 10th evening involving treatment. Dikshit et al (1984)

Cauliflower

Malathion

60

70

80 Cooking seemed to be observed that they are best and lowered the particular TMRL price from 1 week to help totally free days. Jacob and Verma (1989)

Bhindi

Quinalphos

61.84-64.35

43-53

78-82

Both cleanup with water plus salt water cleaning brought decrease that residues underneath your MRL at zero days, baking also did this causing maximum lowering associated 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 magnitude of decontamination was better thanks to cooking in comparison to washing for all insecticides.

Bhatia and

Verma (1994)

Leaves along with curds with cauliflower heads connected with cabbage plus pods of 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 maximum residues.

Water rinse taken out highest DDT residues unlike cooking is effective to eliminate malathion plus carbaryl residues.

Dikshit et al (1986)

Elkins et al (1968)



From the particular on top of kitchen table it could be said which preparing food can be most effective to cut back the residues of different pesticides through various greens however in certain scenarios washing machine with water seemed to be discovered to be effective to lessen the original residues with pesticides plus it has been discovered that will using the growing older regarding residues or using the improve from the sampling days about remedies the result connected with cleaning decreases to remove the particular toxicant towards the same amount seeing that that of samples collected quickly right after spray where boiling as well as food preparation is actually discovered that they are effective. One of the possible basis for higher fraction regarding treatment connected with toxicant from promptly collected selections seeing that nearly all belonging to the residues usually are provide of the surface on the trials plus for that reason it is rather easy to remove s imply by basic washing seeing that witnessed through Dikshit et al (1984,86) Elkins et al (1968), Bhatia along with Verma (1994) as well as Malik et al (1998). With the occasion elapsed your residues are moved within the deeper flesh or highly hold fast on the rough exterior of a number of vegetables. Moreover, your washing is unable to reduce the residues towards the protected degree in comparison to be able to boiling.

There will be quite a few reports exactly where most this three culinary processes proved being inefficient get rid of the residues down below the particular MRL value. According to help Jacob and also Verma (1991) residues involving quinalphos within the treated cauliflower bounty would be lessened exclusively to some extent by way of various house digesting techniques like cleansing plus cooking. Nagesh in addition to Verma (1997) opined the fact that inefficiency on the home functions regarding decontaminating the dealt with cabbage may be from the powerful adsorption components of quinalphos plus chlorpyriphos.

Effect involving family preparing for decontamination regarding pesticide multiresidues inside fruit and veggies

Low quantities with pesticide residues were diagnosed around 97(40%) of mt 243 examples reviewed after using typical loved ones washing, peeling as well as cooking procedures. The number of biological materials that contain detectable residues slipped to 47(19%) following residence preparation. These outcome reveal that will remains stage with most goods are usually substantially lessened following family members preparation (Schattenberg et al., 1996)

Ramesh and also Balasubramanian (1999) executed a survey using vegetables and fruits obtained from Chennai community marketplaces along with fortified having recognised concentrations involving various pesticides as well as decontamination examine with different family members supplements like washing, preparing , peeling causing 65-95% decontamination associated with pesticide residues with diverse development connected with 512 natural current market samples analyzed, the actual organochlorine and organophosphorus pesticides contained in the twelve month period trials had been taken away producing residues very well listed below the actual toxicologically suitable limits.

A short rinse in tap into waters lowers pesticide residues upon many different kinds of produce (Krol et al., 2000). Rinsing removed residues for nine with the twelve pesticides studied. Among captan, chlorothalonil, iprodione, vinclozolin, endosulfan, permethrin, methoxichlor, malathion, diazinon, chlorpyriphos, bifenthrin and also DDE; residues connected with vinclozolin, bifenthrin and chlorpyriphos were not removed. This study confirms that will the water solubility of pesticides won't play a vital function in the actual noticed decrease. The tastes pesticide residues could dwell within the outside involving create exactly where it can be taken off by the clockwork measures connected with rinsing.

Earlier studies from the consequences involving commercial along with house arrangement upon pesticide deposit in vegetables and fruit ended up summarized simply by Zabik (1987). The beginning scientific tests demonstrated remains lowering for being substantial, together with number decrease of chlorinated hydrocarbons position out of 50 to 99+ percentage pertaining to business prep plus out of 14 to 99+ nought per cent pertaining to household prep with the exception involving parathion inside spinach plus broccoli, commercvial plus home prewparation substantially lowered organophosphate residues, when using the decrease in general when i was in the large 80 or perhaps 90% range. Carbamate residues have been lessened by simply 58 that will 99+ per-cent once the vegetables were retail ready-made nevertheless simply by eleven that will 92% inside household preparation.

A the latest review inside Korea sustains these kinds of previously studies (Lee and Lee, 1997). These authors identified in which 45% with the organophosphate residues were eliminated should the meals were cleansed throughout water, 56% using detergent washing, 91% having peeling, as well as 51% by using blanching or perhaps boiling.







Methods connected with multiresidue analysis associated with pesticides within many fruits and fruit and vegetables

Analysis by simply energy chromatography

Nakamura et al (1994) formulated a system pertaining to multiresidue analysis of 48 pesticides (20 organophosphorus, seven organochlorine, 14 organonitrogen and 7 pyrethroid pesticides ) allowed around Japan about the basis of capillary GC once taking out the particular pesticides along with nacetone from vegetable and crops trials as well as using acetonitrile coming from lipid that contains bounty followed by reextraction in to ethyl acetate (test solution). Organophosphorus pesticides were right dependant upon GC-FPD. Organonitrogen pesticides were contingent on GC-FTD (GC-NPD) following clean up by silica serum chromatography. Organochlorine and pyrethroid pesticides had been measured by GC-ECD immediately after cleanse simply by florisil column chromatography. Recoveries regarding twenty herbs at fortification levels connected with 0.05-0.25 ppm have been 42.5-128.5%. the actual recognition boundaries were 0.001 ppm pertaining to organophosphorus along with organochlor ine pesticides and 0.01 ppm pertaining to organonitrogen and also pyrethroid pesticides.

A multiresidue system was employed by Dejonckheere et al (1996) pertaining to determination connected with organochlorine, organophosphorus in addition to organonitrogen pesticides with vegatables and fruits which were extracted with acetone used by simply liquid-liquid dividing along with water:apolar pesticides inside petroleum ether phase, polar pesticides removed from aqueous part with dichloromethane and considered simply by propane chromatography together with electron capture (GC-ECD), fire photometric (GC-FPD) and thermoionic precise (GC-TSD) detection.

The approach utilised intended for multiresidue perseverance of fifty two pesticides including organophosphorus, organochlorine, organonitrogen, specific pyrethroids as well as dithiocarbamate pesticides around fruits and vegetables appeared to be referred to by way of Dogheim et al (1999) utilizing energy chromatography. Samples have been taken by using acetone as well as dividing together with hexane in addition to dichloromethane plus expected by way of GC-ECD along with GC-NPD. Dithiocarbamates were broken down in combination of targeted HCl, SnCl2 in addition to water regarding advancement associated with CS2 that's collected around a good ethanolic answer connected with truck driver acetate and also diethanolamine to form a orange complex. The absorbance associated with orange product appeared to be decided spectrophotometrically with 435 nm. The regular recoveries plus CVs belonging to the 52 pesticides ended up 72-118 and 1-20%, respectively on the spiking levels con nected with 0.01-1 ppm. A similar sorts of technique was as well detailed by way of Kole et al (1998).

Krol et al (2000) used your multiresidue surgery to get determination of 12 pesticides around vegetables where samples have been extracted with 2 propanol in addition to petroleum ether taken through washing together with distilled normal water three times. Final analysis from the samples was performed through GC-ECD, FPD, XSD and/or ELCD.

Ramesah in addition to Balasubramanian (1999) described a solution to figure out organochlorine, organonitrogen plus organophosphorus pesticides throughout fruits and vegetables pursuing extraction with 2-propanol along with petroleum ether by simply mechanised shaker followed by partitioning having distilled water in addition to column cleanup about florisil for OC in addition to OP pesticides. For organonitrogen pesticides this extraction ended up being performed along with acetone followed by partitioning with 10%NaCl and ethyl acetate and column clean up through silica gel. organochlorine, organophosphorus and organonitrogen ingredients were being examined simply by GC-ECD,GC-FPD plus GC-NPD, respectively.

Using GC-ECD, the particular efficiencies with acetonitrile and acetone to herb the particular 8-10 pyrethroids from a few fruit and also plant biological samples had been compared by simply Pang et al (1997). The removal effectiveness of acetone seemed to be ambitious with which associated with acetonitrile with the 6 berry as well as plant samples. The ruggedness medical tests demonstrated further more which the suggested procedure is simple, appropriate by using good accuracy and suitable for multiresidue analysis of pyrethroid in different farming products.

Organophosphorus in addition to organochlorine pesticide residues from fruit and veg by simply capillary GC with electron capture detector (ECD), nitrogen phosphorus detector (NPD), flame photometric detector (FPD) within the sulfur and also phosphorus modes, as well as bulk spectrometry detector (MSD) within selected ion checking (SIM) manner were contingent on Torres et al (1995) next extraction by way of Matrix Solid Phase Dispersion (MSPD) resulting recoveries regarding 41-108% by using general SD connected with 2-14% from the conc. range 0.5-10 g/liter throughout oranges, lemons, grapefruit, pears, plums, lettuces plus tomatoes.

A multiresidue approach as described by Sannino et al (1995) pertaining to quantitative resolve regarding 39 organophosphorus compounds (parent pesticides and their major metabolites) within 7 fatty delt with meals depending on currency trading carbamide peroxide gel permeation chromatography using a Biobeads SX3 column plus a methylene chloride-cyclohexane (15 + 85) eluant after extraction using methylene chloride. Organophosphorus ingredients are quantitated by way of GC-FPD employing OV-1701 plus DB-5 columns. Average recoveries through trials fortified at 0.025-1 mg/kg ranged from 50.6% to get dichlorvos to help 185% for malaoxon. Determination restricts ended up among 0.005 in addition to 0.040 mug/mL. Results were being confirmed by simply fuel chromatography/mass spectrometry by using selected-ion monitoring.

Gas chromatographic circumstances regarding separation plus identification in the compounds were selected utilizing not one but two capillary posts with different polarities and two detectors, ECD as well as NPD intended for multiresidue quantitative willpower with 37 pesticides within vegetables and fruit in addition to in order to study this efficacy of gel-permeation chromatography clean-up right after ethyl acetate removal (Balinova,1999).

Trova et al (1999) performed fresh chromatographic dedication regarding pesticide residues (including azinphos-ethyl, azinphos-methyl, carbaryl, diflubenzuron, dinocap in addition to teflubenzuron) throughout vegetables soon after extraction employing an ethyl acetate/n-hexane solvent system rather than the broadly applied methylene chloride. Recoveries when expected by 'Guidelines pertaining to residues monitoring inside European Union' were observed; that fresh solvent process may be regarded as an alternative to help halogenated compounds, harmful for his or her toxicity and dangerous pertaining to their enviromentally friendly behaviors, in removal connected with HPLC-determinable energetic compounds.

A wide range testing technique was proposed by way of Gelsomino et al (1997) for multiresidue investigation of 77 pesticides (12 organohalogens, 45 organonitrogens, 11 organophosphorus and 9 pyrethroids) in agricultural goods employing gasoline chromatography prepared by long, narrow-bore fused-silica open-tubular copy and electron-capture detector (ECD). Residues were taken along with acetone as well as dichloromethane partitioning and gel permeation chromatographic clean up. Recoveries of many pesticides out of spiked types of carrot, melon plus tomato at fortification ranges of 0.04-0.10 mg/kg ended up 70-108%. Limits associated with detection ended up a smaller amount than 0.01 mg/kg for ECD.

Beena et al (2002, 2003) accomplished supervising connected with veggie selections taking on a multiresidue analytical technique employing GC-ECD plus GC-NPD programs having capillary columns.

Ueno et al (2003) undertook studies an effective along with dependable multiresidue way of figuring out fifty two nitrogen- and/or phosphorus- comprising pesticide residues in a very many vegetable biological materials in which trials were being removed with acetonitrile, and the segregated acetonitrile core has been purified by way of carbamide peroxide gel permeation chromatography in which separated that pesticide eluate into 2 fractoions, that pesticide fractions were respectively purified by just a 2-step minicolumn cleanup, cost-free portion through silica carbamide peroxide gel minicolumn; very first tiny proportion through this tandem minicolumn (florisil minicolumn, inserted upon silica gel minicolumn) that's eluted along with acetone-petroleum ether (3+7). The mixed eluate had been afflicted by combined column gasoline chromatography by using nitrogen-phosphorus in addition to fire photometric detection. Recoveries regarding 52 pesticides through prepared samples ra nged from seventy two in order to 108% by using distant relative ordinary deviations of 2-17%, aside from your recoveries with methamidophos along with chorothalonil. The recognition rules of the actual pesticides had been satisfactory (0.001-0.009 mg/kg) regarding following involving pesticide residues in vegetables.

Menkissoglu et al (2004) carried out a work on the matrix activated effect for 16 common pesticides, most regularly found in monitoring scientific studies with tomato pepper and cucumber, employing a very simple multiresidue method with GC-ECD or maybe NPD, and not using a prior housecleaning step. Anomalously large GC replies plus eventually high recoveries for a number of pesticides inside concentrated amounts had been attained with a conventional calibration together with pesticide answer with ethyl acetate.

A faster, a lesser amount of effective, environmentally more secure supercritical fluid extraction (SFE) approach had been examined by Garcia et al (1996) through traditional sonvent extraction options for that removal associated with imidacloprid, methiocarb, chlorpyrifos, chlorothalonil, endosulfan-1, endosulfan-2 and endosulfan sulfate, through pepper plus tomato making use of veggie sample: anhydrous magnesium sulfate (5:7) recipes to carryout the actual removal with supercritical CO2 as well as HPLC/DAD,GC/ECD and GC/FPD for analysis. The chosen SFE ailments had been three hundred atm, 500C, 200?l involving methanol static modifier, one particular minute static time, along with dynamic extraction using fifteen ml regarding CO2 and also selection in several ml regarding ethyl acetate. Except for imidacloprid, that has been certainly not hauled underneath any belonging to the looked at conditions, pesticide recoveries have been in excess of 80%.

A simplified method is definitely described by simply Chaput (1987) where inverted phase fresh chromatography seemed to be employed along with publish column derivatisation as well as fluorescence detector to know 7 N-methyl carbamates (aldicarb, carbaryl, carbofuran, methiocarb, methomyl, oxamyl and propoxur) and also three similar metabolites throughout fiber rich foods right after removal on the sample together with methanol followed by carbamide peroxide gel permeation chromatography (GPC) or perhaps GPC with on-line Nuclear-celite cleanup to get herbs by using high chlorophyll and/or carotene content (e.g. cabbage as well as broccoli). Recovery information were being acquired by simply fortifying five various bounty (apples, broccoli, cabbage, cauliflower as well as potatoes) at 0.05 and also 0.5 ppm. Recoveries averaged 93% at the two fortification levels. The coefficient associated with alternative belonging to the approach at together levels is usually

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