Page:NIOSH Manual of Analytical Methods - 5034.pdf/2

 OTHER METHODS: This revises Method S208 [2]. Analytical methods for tributyl phosphate (TBP) have been reviewed [3]. Another packed-column GC procedure has been described recently [4]. TBP has been determined in air by capillary-column GC/NPD preceded by sampling on a glass fiber filter or XAD-7 resin [5]. GC/MS [6], LC/MS [7], and LC/TID (thermionic det ection) [8] have all been shown to be useful methods for the analysis of TBP in environmental samples. Finally, a continuous pho sphorus gas analyzer has been used to monitor TBP in air [9].

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

EQUIPMENT:

Diethyl ether *, anhydrous, reagent grade. Tributyl phosphate *, reagent grade. Hydrogen, purified Compressed air, prefiltered Nitrogen, purified Calibration stock solution, tributyl phosphate in diethyl ether



See Special Precautions

1. Sampler: 37-mm mixed cellulose ester membrane filter (0.8-µm pore size) supported by cellulose backup pad in three-piece filter holder. NOTE: Backup filter unit is needed when sampling at temperatures above 23 °C. 2. Personal sampling pump, 1 to 3 L/min, with flexible polyethylene or PTFE tubing. 3. Gas chromatograph equipped with a flame photometric detector, phosphorus filter, and column (p. 5034-1). 4. Electronic integrator or some other suitable method for measuring peak areas. 5. Tweezers. 6. Jars: 2 oz ointment jars for sample extraction, squat form with aluminum-lined screw caps. 7. Syringes, 10-µL and other convenient sizes. 8. Volumetric flasks, 10-mL and other convenient sizes. 9. Pipets, 10-mL and other convenient sizes.

SPECIAL PRECAUTIONS: Store diethyl ether away from heat, light, and sources of ignition in a wellventilated area. Do not leave container open. Diethyl ether can oxidize in air to form explosive peroxides, a reaction accelerated by light. Distillation and evaporation can concentrate unstable peroxides in the residue, a potentially explosive condition [10]. Avoid inhalation of tributyl phosphate vapors and contact with eyes, skin, and clothing [11,12]. Handle only in a hood.

SAMPLING: 1. 2.

3. 4.

Calibrate each personal sampling pump with the representative filter cassettes in line. Remove cassette plugs and connect cassette filter to the personal sampling pump with flexible tubing. NOTE: If ambient temperature is above 23 °C, use two filter cassettes connected in series with a short piece of flexible tubing for sample collection. Some tributyl phosphate may exist as vapor above 23 °C. Sample at an accurately known flow rate of 1 to 3 L/min for a total sample size of 2 to 100 L. Separate front and backup filter cassettes (if two cassettes were used). Firmly seal collected sample cassettes with plugs, and pack securely for shipment.

SAMPLE PREPARATION: 5.

Transfer the filter and backup pad to an ointment jar using tweezers. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94