Page:NIOSH Manual of Analytical Methods - 5519.pdf/2

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ENDRIN: METHOD 5519, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3. 4. 5.

6.

EQUIPMENT:

Toluene, ACS reagent grade or better. Hexane, ACS reagent grade or better. Xylene, ACS reagent grade or better. Endrin.* Calibration stock solution, 3 mg/mL. Dissolve 30 mg endrin in 1 mL xylene and dilute to 10 mL with hexane. 95% Argon/5% methane mixture, purified.

See SPECIAL PRECAUTIONS.

1. Sampler: 37-mm, 0.8-µm pore size MCEF filter supported by a stainless steel screen in cassette filter holder followed by a 7 cm x 8-mm OD x 6-mm ID, glass tube, flame-sealed with plastic caps, containing 20/40 mesh Chromosorb 102 (front = 100 mg; back = 50 mg), separated by 3-mm silanized glass wool plug. Pressure drop across the tube at 1 L/min must not exceed 3.4 kPa. Tubes commercially available (SKC #226-49-20-102 or equivalent). 2. Personal sampling pump, 0.5 to 1 L/min, with flexible connecting tubing. 3. Gas chromatograph, electron capture detector, integrator and column (page 5519-1). 4. Vials, glass, scintillation, 20-mL, PTFE-lined caps. 5. Syringe, 10-µL, readable to 0.1-µL. 6. Volumetric flasks, 10-mL. 7. File, triangular. 8. Pipets, 5- and 10-mL. 9. Tweezers.

SPECIAL PRECAUTIONS: Endrin is absorbed through the skin. Gloves and safety glasses must be used to avoid direct contact with this compound. Handle all chemicals and organic solvents in the laboratory hood.

SAMPLING: 1. 2.

3. 4. 5.

6. 7.

Calibrate each personal sampling pump with a representative sampler in line. Break the ends of the tube immediately before sampling. Connect the Chromosorb tube to the cassette with a short piece of tubing. Connect the tube to the pump with backup section nearest the sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.5 and 1 L/min for a total sample size of 12 to 400 L. Remove the cassette from the sampling train, carefully remove the filter from the cassette with tweezers and place it in a clean vial. Reassemble the cassette and plug the inlet and outlet. Score the Chromosorb tube in front of the front section and break the tube at score line. Transfer the front (larger) section of sorbent and the glass wool plug to the scintillation vial containing the filter. Cap the ends of the sampling tube containing the backup section and ship along with the sample vial. In a separate package, ship bulk sample of the suspected material in a vial.

SAMPLE PREPARATION: 8. 9.

Transfer the backup sorbent section and associated glass wool plugs to a clean vial. Add 5.0 mL toluene to each vial (filter + front sorbent section in one vial and back sorbent section in another vial). Cap each vial. Allow to stand, with occasional swirling, for 15 min.

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