Page:NIOSH Manual of Analytical Methods - 5007.pdf/2

 ROTENONE: METHOD 5007, Issue 2, dated 15 August 1994 - Page 2 of 3 REAGENTS: 1. 2. 3. 4. 5.

6.

EQUIPMENT:

Acetonitrile, HPLC grade.* Methanol, HPLC grade. Rotenone, 97% purity. Water, distilled, HPLC grade. Calibration stock solution, 3 mg/mL. Dissolve 0.075 g Rotenone in 25 mL acetonitrile. Prepare fresh daily in duplicate. Recovery stock solution, 50 mg/mL. Dissolve 0.500 g Rotenone in acetone. Dilute to 10 mL. Prepare fresh daily.


 * See SPECIAL PRECAUTIONS.

1. Sampler: 37-mm, two-piece cassette containing 1-µm PTFE membrane filter with backup pad. NOTE: Use an opaque cassette or otherwise shield the filter from light to minimize photodecomposition of Rotenone during and after sampling. 2. Personal sampling pump, 1 to 4 L/min, with flexible connecting tubing. 3. HPLC, UV detector, integrator and column (page 5007-1). 4. Jars, ointment, 60-mL, with PTFE-lined caps. 5. Vials, 4-mL, with PTFE-lined caps. 6. Syringes, 5-mL. 7. Filtration device, Swinney 13-mm with 1-µm PTFE filters, or PTFE syringe filters. 8. Volumetrics, 10- and 25-mL. 9. Syringes, microliter, for sample injection and standard preparation. 10. Pipet, 4-mL, with pipet bulb.

SPECIAL PRECAUTIONS: Avoid breathing acetonitrile vapors; may cause skin irritation.

SAMPLING: 1. 2. 3.

Calibrate each personal sampling pump with a representative sampler in line. Sample at an accurately known flow rate between 1 and 4 L/min for a total sample size of 8 to 400 L. Do not exceed 2 mg total dust loading on the filter. Collect a bulk sample (1 g) in a glass vial with PTFE-lined cap; ship separately from filters.

SAMPLE PREPARATION: 4. Open filter cassette; transfer filter to ointment jar. 5. Add 4.0 mL acetonitrile; gently swirl for 30 min. 6. Filter each sample using a 5-mL syringe with PTFE syringe filter or Swinney filtration device. Deliver filtrate to a 4-mL vial. CALIBRATION AND QUALITY CONTROL: 7. Prepare at least six working standards daily in the range 0.01 to 1 mg Rotenone per sample. a. Add known amounts of calibration stock solution to acetonitrile in 10-mL volumetric flasks and dilute to the mark. b. Analyze together with samples and blanks (steps 9 and 10). c. Prepare calibration graph (peak area vs. mg Rotenone). 8. Check recovery (R) with at least three spiked media blanks per sample set in the calibration range (step 7). a. Add aliquots of recovery stock solution to blank filters with a microliter syringe. Air dry. b. Analyze together with working standards (steps 4 through 6, 9 and 10). c. Calculate recovery [(mg recovered - mg blank)/mg added]. d. Prepare recovery graph (R vs. mg Rotenone).

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94