Page:NIOSH Manual of Analytical Methods - 5039.pdf/2

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CHLORINATED CAMPHENE: METHOD 5039, Issue 1, dated 15 August 1994 - Page 2 of 3

REAGENTS:

1. Chlorinated camphene* (toxaphene). 2. Petroleum ether*, 30 to 60 °C, suitable for pesticide residue analysis. 3. Nitrogen, purified. 4. Calibration stock solution, 0.1 mg/mL. Dissolve 5 mg of chlorinated camphene in 50 mL petroleum ether.

  • See SPECIAL PRECAUTIONS.

EQUIPMENT:

1. Sampler: 37-mm cellulose ester membrane filter (0.8-µm pore size) supported by a cellulose backup pad in a three-piece filter holder. Do not use tenite filter holders. 2. Personal sampling pump, 0.2 to 1 L/min, with flexible connecting tubing. 3. Gas chromatograph, 63Ni ECD, integrator, and column (page 5039-1). 4. Vials, 20-mL with PTFE-lined screw caps for shipping filters and pads. 5. Syringes, 10-µL and larger sizes for preparation of standard solutions. 6. Pipet, 10-mL. 7. Volumetric flasks, 10-mL. 8. Tweezers, stainless steel.

</LINE/> SPECIAL PRECAUTIONS: Petroleum ether is highly flammable. Prepare samples and standards in well-ventilated hood. Overexposure to chlorinated camphene may cause nausea, mental confusion, and unconsciousness; contact with chlorinated camphene solutions may cause skin irritation [4].

SAMPLING:

1. Calibrate each personal sampling pump with a representative sampler in line. 2. Sample at an accurately known flow rate between 0.2 and 1 L/min for a sample size of 2 to 30 L. 3. Carefully transfer the filter and backup pad to a screw cap vial by means of tweezers.

SAMPLE PREPARATION:

4. Pipet 10 mL petroleum ether into each vial and seal. 5. Gently swirl the vial to wet the filter and backup pad. Allow to stand 30 min.

CALIBRATION AND QUALITY CONTROL: 6.

7.

8.

Calibrate daily with at least six working standards. a. Add known amounts of calibration stock solution to petroleum ether in 10-mL volumetric flasks and dilute to the mark to obtain concentrations in the range 0.14 to 14 µg chlorinated camphene/10 mL. b. Analyze with samples and blanks (steps 9 and 10). c. Prepare calibration graph (sum of peak areas in the retention time band vs. µg chlorinated camphene). Determine recovery (R) at least once for each batch of filters used for sampling in the working range. Prepare three filters at each of five levels plus three media blanks. a. Deposit a known amount of calibration stock solution onto the filter. Allow filters to air dry. b. Store samples overnight in vials. c. Prepare (steps 4 and 5) and analyze with samples (steps 8 and 9). d. Prepare a graph of R vs. µg chlorinated camphene recovered. Analyze three quality control blind spikes and three analyst spikes to ensure that the calibration graph and R graph are in control. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94