Page:NIOSH Manual of Analytical Methods - 9205.pdf/2

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CAP TAN and T HIOP HAN ATE -MET HYL: M ETH OD 9205, Issue 1, dated 1 5 Ma rch 2003 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. 2. 3. 4. 5. 6.

7. 8. 9.

10.

11.

Isop ropa nol, H PLC pesticide grade .* Aceton itrile, HPL C grade .* Triethylam ine (T EA).* Ortho-phosphoric acid >85% by weight, ACS grad e or b etter.* Deionized water. Extraction solution: 40% isopropanol/60% acetonitrile w/2 mL TEA-PO 4 preservative for every liter of extraction solution prepared. Thiophanate-methyl * stock solution, 10 mg/m L. Prepare in acetonitrile. Ca ptan * (Ch em Service) stoc k solution, 5 mg/m L. Prepare in acetonitrile. TEA-PO 4 Preservative. Dissolve 1.4 mL of TEA in 90 mL of deionized water in a 100 mL volumetric flask. Add phosphoric acid to lower pH to 7.0(± 0.1) as indicated by a calibrated pH m eter. B ring vo lum e to 100 m L with w ater. Keep tightly capped and refrigerated. Solution stable for 12 months. Mobile phase A. Com bine 20 mL of npropanol and 2.8 m L T EA in a 1 L volum etric flask and bring to volume using deionized wate r. Adju st pH to 7.0 (+/- 0.1) with phosphoric acid using a pH m eter. Final concentrations: 2% n-propanol, 0.02 M TEAPO 4. Degas prior to use. Mo bile phase B. Ad d 20 m L of n -propan ol to acetonitrile in a 1 L volumetric flask and bring to volume. Degas prior to use.

1. Dermal Patch: Texwipe™ AlphaW ipe® polyes ter cleanro om wipe (4" x 4") in holder. The wipe is available com m ercially. 2. Patch Holder: W hite, 2-side chipboard, 0.08 SBS with a 7.6 cm diameter circle cut in one side (W ellman C ontainer Corp, Fairfield, Ohio). 3. High Performance Liquid Chromatograph (HPLC ). 4. Autosampler capable of 5 µL injections. 5. An alytic al colum n: P henom enex® Synergi™ 4µ Hydro-RP 80A (250 mm x 2.00 mm) or equ ivalent. 6. UV detector at 200 nm. 7. Vials, 2 mL, PTFE-lined caps. 8. Centrifuge tubes, polypropylene, 50 mL. 9. Syringes, 50-:L, 1-mL, and 5-mL. 10. Volumetric flasks, 5-mL, 100-mL, and 1-L. 11. PTFE syringe filter, 4-mm , 0.45-µm pore. 12. Large vial/tube rotator. 13. pH m eter. 14. Graduated cylinders, 50-mL. 15. Pipettes, glass, disposable, 2-mL. 16. Forceps. 17. Bagge d refrigera nt.

  • See SPECIAL PRECAUTIONS

SPECIAL PRECAUTIONS: Th iophana te-m ethyl: Avo id inhaling vap ors or du st; avo id sk in con tact. W ear glo ves and suitab le cloth ing when handling pure m ate rial. So lvents: Avoid sk in contac t and open flam e. Us e in a h ood . Pho sph oric acid: Avoid s kin c onta ct. Ca ptan : Use in ho od. A void c onta ct with sk in, eyes, and clothing an d inge stion o r inhalation. Eye protection sho uld be worn. SAMPLING: 1. Secure the patch m aterial in the pa tch holder with staples at two opposite corners. Attach the patch and holder to the appropriate location of the skin or clothing and sample for designated time period. 2. At the end of the sampling time, remove the patch from holder using clean forceps and trans fer to a 50-m L centrifuge tube. 3. Label and pack the tube securely for shipment. These are shipped cold with other samples. 4. Sam ples should be stored under refrigeration until needed for analysis.

SAMPLE PREPARATION: 5. Add 30 mL of extraction solvent to each centrifuge tube and recap. 6. Mix by rotating the tubes end-over-end fo r at least one hour. 7. Filter an extra ct aliquot into a 2-m L au tosa m pler vial throug h a 4-m m , 0.45 µm pore , PT FE filter.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition