Page:NIOSH Manual of Analytical Methods - 2514.pdf/2

 ANISIDINE: METHOD 2514, Issue 2, dated 15 August 1994 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. 2. 3. 4. 5. 6. 7.

8.

p-Anisidine, reagent grade.* o-Anisidine, reagent grade.* Methanol, HPLC grade.* Acetonitrile, HPLC grade.* Water, distilled, deionized. Methylene chloride. Calibration stock solution, 15.0 mg/mL p-anisidine and 15.3 mg/mL o-anisidine. Dissolve 750 mg p-anisidine and 700 µL o-anisidine in methanol to make 50 mL solution. HPLC mobile phase: 35% acetonitrile/65% water. Filter (5-µm PTFE) and degas prior to use.
 * See SPECIAL PRECAUTIONS.

1.

2. 3.

4. 5. 6. 7.

Sampler: glass tube, 7 cm long, 8-mm OD, 6-mm ID, with plastic caps, containing two sections of 20/50 mesh XAD-2 (front = 150 mg; back = 75 mg) separated and held in place by plugs of silylated glass wool. Pressure drop across the tube must be <3.4 kPa (2.5 cm Hg) at 1 L/min airflow. Tubes are commercially available, (SKC Cat. No. 226-30-05, or equivalent). Personal sampling pump, 0.5 to 1 L/min, with flexible connecting tubing. HPLC with UV absorption detector at 254 nm, integrator and column (page 2514-1). Vials, 20-mL, scintillation. Pipet, 5-mL. Syringes, 10-µL, readable to 0.1 µL. Volumetric flasks, 5- and 50-mL.

SPECIAL PRECAUTIONS: Anisidine can irritate the skin. Methanol and anisidine can be absorbed through the skin. Avoid inhalation of vapors of these compounds and of acetonitrile [4].

SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with a representative sampler in line. Uncap the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.5 and 1.0 L/min for a total sample size of 24 to 320 L. Do not sample at less than 0.5 L/min. Cap the samplers. Pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Place the front and back sections of the sampler in separate vials. Discard the glass wool plugs. Add 5.0 mL methanol to each vial. Cap each vial and swirl vigorously. Allow to stand for 15 min. Analyze within one day.

CALIBRATION AND QUALITY CONTROL: 8.

9.

Calibrate daily with at least six working standards over the range 0.4 to 360 µg anisidine per sample for each isomer. a. Add a known volume of calibration stock solution, or a dilution thereof in methanol, to a 5-mL volumetric flask and dilute to the mark with methanol. b. Analyze together with samples and blanks (steps 11 and 12). c. Prepare calibration graph (peak area vs. µg analyte) for each isomer. Determine desorption efficiency (DE) at least once for each lot of XAD-2 used for sampling in the concentration range of interest. Prepare four tubes at each of five levels. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94