Page:NIOSH Manual of Analytical Methods - 5504.pdf/2

 Organotin Compounds (as Sn): Method 5504, Issue 2 dated 15 August 1994 - Page 2 of 6 REAGENTS:

EQUIPMENT:

1. 2. 3. 4. 5. 6. 7. 8. 9.

1. Sampler: glass fiber filter, 37-mm (Gelman Type AE or equivalent) in cassette filter holder followed by XAD-2 sorbent tube, 80 mg front section/40 mg back section separated and retained by silanized glass wool (SKC, Inc., Eighty-Four, PA 15330, Cat. No. 22630). 2. Personal sampling pump, 1 to 1.5 L/min, with flexible connecting tubing. 3. Shipping container, refrigerated, with dry ice. 4. High performance liquid chromatograph (HPLC), interfaced with autoinjection system (Fig. 1), with binary solvent capability, solvent gradient capability and columns: a. non-tetraorganotin species: cation exchange column (Whatman, Inc., Partisil-10 Strong Cation Exchange Column and Solvecon Pre-Column Kit). b. tetraorganotin compounds: C18 column, (Whatman, Inc., Lichrosorb). 5. Atomic absorption spectrophotometer (AAS) having recorder output proportional to absorbance units, graphite furnace accessory (pyrolytic with Zr coating, coated L'vov platform may be required; see APPENDIX), sample autoinjection system with moving sample tube rack or carrousel (Fig. 1), automatic micropipettor for accurately injecting 20-µL sample aliquots into graphite furnace, background correction (e.g., D2 or H2 lamp) capability, and tin electrodeless discharge lamp or hollow cathode lamp. 6. Bath, ultrasonic. 7. Volumetric flasks, 10-mL. 8. Syringe, 20-µL, readable to 0.5 µL. 9. Beakers, Phillips, 125-mL. 10. Pipets, 5- and 10-mL; 10- and 100-µL. 11. Oven or muffle furnace, 200 EC. 12. Plastic film.

Zirconium acetate oxide, reagent grade. Ammonium acetate, reagent grade. Diammonium citrate, reagent grade. Acetonitrile, chromatographic grade. Deionized water. Acetic acid, glacial, reagent grade. Methanol, chromatographic grade. Acetic acid, 0.1% (v/v) in acetonitrile. Acetate buffer solution (v/v) 70% methanol, 27% deionized water, 3% aqueous 1 M ammonium acetate. 10. Citrate buffer solution (v/v) 70% methanol, 26.8% deionized water, 3% aqueous 1 M diammonium citrate in 0.2% (v/v) glacial acetic acid. 11. Organotin standard solutions, 1000 µg/mL (as Sn), prepared from pure organotin compounds in 0.1% (v/v) acetic acid in acetonitrile. 12. Calibration stock solution, 10 µg/mL (as Sn). Prepare a standard mixture of the organotin compounds of interest. Pipet 0.1 mL of each organotin standard solution into a 10-mL volumetric flask. Dilute to the mark with 0.1% (v/v) acetic acid in acetonitrile. Prepare fresh daily.

SPECIAL PRECAUTIONS: None. SAMPLING: 1. Calibrate each personal sampling pump with a representative sampler in line. 2. Break the ends of the sorbent tube immediately before sampling and connect to the filter with a short piece of tubing. Attach sampler to personal sampling pump with flexible tubing. 3. Sample at an accurately known flow rate between 1 and 1.5 L/min for a total sample size of 50 to 500 L. 4. Cap the samplers. Pack securely for shipment in dry ice. NOTE: The cassette and sorbent tube should remain connected for storage. Store samples at less than 0 EC. Analyze within seven days after collection. SAMPLE PREPARATION: NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94