Page:NIOSH Manual of Analytical Methods - 5038.pdf/2

 TRIPHENYL PHOSPHATE: METHOD 5038, Issue 1, dated 15 August 1994 - Page 2 of 3 REAGENTS: 1. 2. 3. 4. 5. 6.

EQUIPMENT:

Diethyl ether, anhydrous, reagent grade. Triphenyl phosphate,* reagent grade. Hydrogen, purified. Compressed air, prefiltered. Nitrogen, purified. Calibration stock solution (10-600 µg triphenyl phosphate per 10 mL diethyl ether).



See Special Precautions

1. Sampler: 37-mm cellulose ester membrane filter (0.8-µm pore size) with cellulose backup pad held in a three-piece cassette filter holder supported by a cellulose backup pad. 2. Personal sampling pump @ 1 to 3 L/min, with flexible tubing. 3. Gas chromatograph equipped with a flame photometric detector, phosphorus filter, and column (p. 5038-1). 4. Electronic integrator or other suitable method for measuring peak areas. 5. Ointment jars, 2 oz., squat form with aluminum-lined screw caps. 6. Syringes, 10-µL and other convenient sizes for preparing standard solutions. 7. Pipets, 10-mL and other convenient sizes for preparing standard solutions.

SPECIAL PRECAUTIONS: Repeated exposure to triphenyl phosphate through inhalation or ingestion may cause minor changes in blood enzymes. Triphenyl phosphate also causes neurotoxic effects in animals; therefore, persons with pre-existing neuromuscular disorders may be at increased risk.[2] Handle only in a fume hood. Avoid skin contact.

SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with a representative filter cassette in line. Remove the cassette plugs and attach to the personal sampling pump with flexible tubing. Sample 10 to 400 L or more of air at an accurately known flow rate of 1 to 3 L/min. Seal the collected sample cassette firmly with plugs. Pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Transfer cellulose membrane filter and cellulose backup pad with tweezers to an ointment jar. Pipet 10.0 mL of ether into each jar. Seal the jar immediately to minimize evaporation. Allow samples to stand for at least 30 minutes with occasional agitation.

CALIBRATION AND QUALITY CONTROL: 8.

9.

Calibrate daily with at least six working standards over the range 10 to 900 µg TPP per sample. a. Add know amounts of calibration stock solution to cover the range of interest to 10.0-mL volumetric flasks and dilute to the mark with diethyl ether. b. Analyze working standards together with samples and blanks (steps 11 and 12). c. Prepare a calibration graph of peak area vs. µg of triphenyl phosphate per 10-mL sample. Determine recovery for each lot of filters used for sampling in the concentration range of interest. Prepare three filters at each of five levels plus three media blanks. a. Spike aliquot of calibration solution onto each filter. b. After air-drying, extract filters in 10 mL diethyl ether (steps 5 through 7). c. Analyze together with working standards. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94