Maneb Hand Wash (3601)
MANEB Hand Wash C4H6N2S4Mn
MW:
265.2
METHOD: 3601, Issue 1
CAS: 124-38-2
3601
RTECS: OP07000
EVALUATION: PARTIAL
OSHA : not applicable NIOSH: not applicable ACGIH: not applicable
PROPERTIES:
Issue 1: 15 March 2003
powder, yellow, wettable; sparingly soluble in water and organic solvents; vp not significant
NAMES & SYNONYMS: manganous ethylenebis(dithiocarbamic acid), Manzate; Dithane M-22
SAMPLING
MEASUREMENT
SAMPLER:
PLASTIC BAG containing hand-wash solution,150 mL
SHIPMENT:
add 1 g L-cysteine, 3 g Na4 EDTACH2 O to each sample, ship in refrigerant packs, 4 °C, via overnight express
SAMPLE STABILITY:
at least 1 week at 4 °C
BLANKS:
2 to 10 field blanks per set
ACCURACY RANGE STUDIED: BIAS:
not determined not determined
OVERALL PRECISION ( Ö r T ): not determined ACCURACY:
TECHNIQUE:
HPLC, UV detection
ANALYTE:
ethylenebisdithiocarbamate anion
INJECTION VOLUME:
100 µL
MOBILE PHASE: 0.0675 M phosphate, 0.0525 M NaClO4 , pH 6.9, 1 g/L Na2 EDTA C2H2 O, 2 mL/min COLUMN:
Dionex AS7 anion exchange column, GS7 guard column or equivalent
DETECTOR:
UV, 285 nm (8 max) or 254 nm
CALIBRATION:
solutions of Maneb in 1% L-cysteine, 3% Na2 EDTA
RANGE:
0.03 to 15 mg/sample [1]
ESTIMATED LOD: 0.2 µg/mL or 0.03 mg/sample [1] PRECISION ( þ r ):
0.015 [1]
not determined
APPLICABILITY: This method determines Maneb washed from the hands of workers. It is applicable to the determination of Zineb, Mancozeb, and Nabam since these all convert to the same analyte when dissolved in EDTA solution.
INTERFERENCES: Not thoroughly investigated. No interferences have been found during method development.
OTHER METHODS: Maneb can also be determined by first methylating followed by HPLC analysis with a C18 column [2-5].
NIOSH Manual of Analytical Methods, Fourth Edition MA NEB , Hand W ash: ME TH OD 3601, Issue 1, dated 1 5 Ma rch 2003 - page 2 of 5 REAGENTS:
EQUIPMENT:
1. Maneb*, purity > 90% 2. W ater, deionized 3. Mobile Phase, 0.0675 M phosph ate buffer, 0.0525 M Na ClO 4, 1 g/L Na2EDTAC2H 2O: In a 1-L volumetric flask, dissolve 4.79 g dibasic sodium phosphate ; 4.5 9 g m onobasic potassium phosphate; 6.43 g sodium chlorate; 1 g ethylenediaminetetraacetic acid, disodium salt, dihydrate in 500 m L of deionized water. Bring to volume with deionized water. Adjust pH to 6.9. 4. L-cysteine, reagent grade. 5. Ethylenediaminetetraacetic acid, disodium salt, dihydrate (Na 2EDTAC2H 2O), reagent grade. 6. Sodium phosphate, dibasic, anhydrous (Na2HPO 4), reagent grade. 7. Potassium phosphate, monobasic, anhydrous (H 2PO 4), reagent grade. 8. So dium chlorate (NaC lO 3), reagent grade. 9. Ethylenediaminetetraacetic acid, tetrasodium salt, dihydrate (Na 4EDTAC2H 2O)*. 10. Triton-X-100 solution: 1 mL Triton-X-100 plus 50 m L water. 11. Diluting solution: 1% L-cysteine, 3% Na 4EDTA•2H 2O in water. Prepare as follows: Dissolve 10 g of L-cysteine and 30 g of Na 4EDTA•2H 2O in 50 m L of de ionized water in a 1-L volum etric flas k. D ilute to volum e with deionized water. (The pH will be app roximately 8.6*.) 12. Calibration stock solution*: Dissolve 10 mg of Maneb in 10 mL diluting solution.
1. Sam pler: Plastic bags, polyethylene, 2 quart size, freezer bag type, containing 150-m L hand wash solution. 2. High performance liquid chromatograph (HPLC) with UV detector, 254 nm (or 285 nm if a variable-wa velength UV detec tor is available). Set chromatograph to conditions on page 3601-1. 3. Ultrasonic water bath. 4. Graduated cylinder to measure water for hand wash 150 mL. 5. Bottles, glass, amber, wide-mouth, 75- to 125mL, with PTFE-lined screw caps.
- See SPECIAL PRECAUTIONS
SPECIAL PRECAUTIONS: Maneb has degradation products which are known to be carcinogenic, m utagenic, and teratogenic [6-9]. Avoid contact with Mane b by wearing appropriate protective equipment. Na 4EDTA is very alkaline; avoid contact with skin or eyes of either the dry powder or aqueous solutions.
SAMPLING: NOTE: The sam pling procedure has not been thoroughly inve stig ate d; th is is a prototyp e m eth od only. 1. Pour 150 mL of water into a plastic bag. Record the total volume of water in the bag. 2. Add 5 drops of Triton-X-100 solution to the water in the bag. 3. Ask the worker to insert his hand into the water and, w hile holding the bag closed around his arm, shake his hand in the water for approximately 30 seconds. 4. After removing the hand from the bag, add 1 g L-cysteine and 3 g Na4EDTA•2H 2O to the bag. NOT E 1: The ED TA here m ust be the tetras od ium for m , no t the dis odium form. See SPECIAL PRECAUTIONS. NIOSH Manual of Analytical Methods, Fourth Edition MA NEB , Hand W ash: ME TH OD 3601, Issue 1, dated 1 5 Ma rch 2003 - page 3 of 5
5. 6. 7. 8.
NOT E 2: Preweighing the L-cysteine and the EDTA into small vials is a convenient way of dispensing these chemicals in the field. NOTE 3: The addition of EDTA and L-cysteine to the hand-wash solution before washing the hand is not recomm ended, becaus e these che m icals will mak e the hand-w as h s olu tion very alkaline, slippery, and have a n unpleasan t odor (from the L-cysteine). Shake the bag until all the L-cysteine and EDTA dissolve. Pour the hand-wash solution from the bag into a 75- to 125-m L am ber wide-m outh bottle to overflowing and cap with no headspace. Prepare a blank sample by following all steps above, except step 3. Pack securely for shipment in refrigerant packs to keep at approximately 4 / C, and ship via overnight express.
SAMPLE PREPARATION: 9. On arrival at the laboratory, store the samples at 4 / C. 10. Put capped sam ple bo ttles in the ultrasonic bath for 5 to 10 m inutes . 11. Transfer 1 to 2 mL of each hand-wash solution, standard, and blank to an autosampler vial for analysis. An alyze with in 24 hours. No fu rther sam ple pre paration is necessary.
CALIBRATION AND QUALITY CONTRO L: 12. Calibrate daily with at least six working standards over the range of 0.1 to 100 µg/mL. a. Pipet aliquots of c alibration stoc k solution into 10 -m L volum etric flas ks, and bring to volum e with diluting solution. b. Include a calibration blank of unspiked diluting solution. c. Analyze together with field sam ples, field blanks, and laboratory control samples (steps 14 through 16). d. Prepare a calibration graph (pe ak area vs. concentration, µg/m L). 13. Prepare Lab orato ry Control Sam ples (LC S), in du plicate, with ea ch s am ple se t. a. Ind ependently prepare quality control Maneb L CS s olu tions in aqueous 1% L-cysteine, 3% Na 4EDTA•2H 2O at concentrations within the analytical range. b. Analyze along with the field sam ples, blanks, and liquid standards (steps 14 through 16).
MEASUREMENT: 14. Set liquid chrom atograph to m anufacturer’s recom m endations and the param eters given on page 3601-1. 15. Inject sample aliquots (100 µL) manually or with an autosampler. Rinse and dry syringe after each injection. 16. Mea sure peak areas. If sample peak area exceeds the linear calibration range, dilute with an aqueous 1% L-cysteine, 3% Na 4EDTA•2H 2O solution, reanalyze, and apply the appropriate dilution fa cto r in calculations.
CALCULATIONS: 17. From the calibration graph, read the concentration, C (µg/mL), of Maneb found in the sample. 18. Calculate the m ass of M aneb, M (µg), in the hand wash s am ple volume , V (mL ).
NIOSH Manual of Analytical Methods, Fourth Edition MA NEB , Hand W ash: ME TH OD 3601, Issue 1, dated 1 5 Ma rch 2003 - page 4 of 5 CONFIRMATION: No confirm ation me thod has be en tested. The re are several poss ible alternatives , such as ion-pairing chrom atog raph y with a C -18 c olum n [5], or ana lysis of m ethylated de rivatives on a C-1 8 co lum n [3,4].
EVALUATION OF METHOD: This method has been evaluated in the laboratory only. No field samples have been analyzed to date. LOD/LOQ A series of liquid standards from 0.1 to 100 µg/mL was prepared in duplicate, analyzed , and fitted with a linear curve. The Limit of Detection (LOD), 0.2 µg/mL, and L im i t o f Q uantitation (LOQ), 0.66 µg/mL, were es timated with the NIO SH SO P 01 8 m etho d [10]. PRECISION AND ACCURACY Twenty-four liquid standards were prepared, six at each of four levels: 3xLOQ, 10xLOQ, 30xLOQ, and 100xLOQ. The relative standard deviation of the 100xLOQ level was considerably lower than that of the other three levels and, there fore, was not used to com pute the pooled relative standa rd de viation. The pooled rela tive sta ndard deviation fo r the first th ree levels was 0.015 . Since all samples w ere spike d liquid standards, accuracy and bias were not determined. Since no samples were generated, overall precision was not calculated. STABILITY Stab ility studies were performed on solutions at 6.6 µg/mL Maneb concentration. It was determined that it is necessary to store the samples at 4 / C in a solution of 1% L-cysteine, 3% Na 4EDTA•2H 2O. Samples stored at 4 / C were stable to 30 days with greater than 90% recovery with or without headspace. At 24 / C, however, samples with headspace deteriorated more rapidly. Therefore, as a precaution against the pos sibility of elevated temperatures during shipping, samples should be stored and shipped with no headspace.
COM MEN TS: Most ethylene-bis-dithioc arba m ates (EB DC ) con taining divalen t (or higher) m etals, (e.g., Maneb, Mancozeb, and Zineb) dissolve with difficulty in alm ost every so lvent. If the m etal ion is rem oved by co m plexation w ith EDTA (at high pH), the EBDC will dissolve but will begin to deg rade rapidly, presu m ably by ox idation, to disulfides or other products. Adding an an tioxidant such as L-cysteine greatly inhibits this oxidative degradation. Excluding headspace air has bee n sh own to assist in reduc ing ox idation; how ever, coo ling to 4 / C is one of the most important factors in sample preservation.
REFERENCES: [1] [2]
[3] [4] [5]
[6] [7]
DataChem Laboratories [1995]. Backup Data Report for Maneb, dermal patch and hand wash. Unpublished report, DataChem Laboratories, Salt Lake City, UT. Bardarov V,. Zaikov Chr, Mitewa M [1989]. Application of High-Performanc e Liquid Chromatography with Spectrophotom etric and Electrochem ical De tec tion to th e Analysis of A lkyle nebis(dithiocarbamates) and their M etab olites. Journ al of C hrom atog raph y, 479: 97. Gustafsson KH, Thompson R A [1981]. High-Pressure Liquid Chrom ato grap hic Determination of Fungicidal Dithiocarbam ates . J. Agric. Fo od C hem . 29: 729. Gustafsson, KH , Fah lgren CH [1983]. Determination of Dithiocarbamate Fungicides in Vegeta ble Foods tuffs by High -Perform anc e Liqu id Ch rom atog raph y. J. Agric. Foo d Chem . 31: 461. Irth H, De Jong GJ, Frei RW , Brinkm an UATh [1990]. Determination of Dithiocarbamates in Residues by Liquid Chromatography with Selective Precolumn or Reaction-Detection Systems. Intern J Environ Anal Ch em . 39: 129. Seiler J.F [1 974 ]. Mutat. Re s. 26: 189. Vogeler K, D reze P , Rapp A , Steffan S H, U llem eyer H [1977]. Pflanzen sch utz-N ach r, 30: 72.
NIOSH Manual of Analytical Methods, Fourth Edition MA NEB , Hand W ash: ME TH OD 3601, Issue 1, dated 1 5 Ma rch 2003 - page 5 of 5 [8] [9] [10]
Innes JR M, Va lerio M, Ulland B, Pallotta AJ, Petruccelli L, Batres R R, Fa lk H L, G art JJ , Kle in M, Mitchel I, Peters J [1969]. J. N atl. Cance r Inst. 42: 1101. Kh era, K S [1 973]. T etrato logy 7: 243. NIOSH [1994]. NIOSH SO P 018, NIOSH/DPSE Quality Assurance Manual (December 1983). issued Jan. 24, 1984, Revised July 18.
METHOD WRITTEN BY: Paul C. Gillespie and John M. Reynolds, DataChem Laboratories, Salt Lake City, UT.
NIOSH Manual of Analytical Methods, Fourth Edition