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BROMOXYNIL and BROMOXYNIL OCTANOATE: METHOD 5010, Issue 2, dated 15 August 1994 - Page 3 of 3

MEASUREMENT: 7.

8.

9.

Set the liquid chromatograph to the conditions on page 5010-1 using the following mobile phase gradient: 50% CH 3CN/50% H 2O for 10 min; 10 min gradient to 100% CH 3N; hold 10 min; 2 min gradient to 50% CH 3CN/50% H 2O; hold 15 min. Inject 100 µL sample extract with a high-pressure syringe or a sampling loop. Record the volume injected to the nearest 0.5 µL. Under these conditions, the retention times are 3.6 min for Bromoxynil and 33 min for Bromoxynil octanoate. Measure peak area. NOTE: If the peak area exceeds the linear range of the system, dilute with acetonitrile and reanalyze. If the peak area measurement is hindered by the presence of interferences, other chromatographic conditions may be required.

CALCULATIONS: 10. 11.

Read the mass of analytes (including appropriate aliquot factors) in the sample extract, W (µg), and average media blank, B (µg), from the calibration graph. Determine the concentrations, C (mg/m 3), of each analyte in the air volume sampled, V (L):

EVALUATION OF METHOD: This method was developed with laboratory samples during the period June to September, 1983 [1]. PTFE-coated glass fiber filters were spiked with 50 µg Bromoxynil and 90 µg Bromoxynil octanoate, after which 90 L of clean air at 80% RH was drawn through the filters. Recoveries averaged 93% for Bromoxynil and 100% for Bromoxynil octanoate with relative standard deviations, Sr, of 0.046 and 0.020, respectively. Storage at ambient conditions for 14 days gave recoveries of 70 to 80% for both compounds, while storage under refrigeration for 25 days or at ambient conditions for two days followed by refrigeration for 23 days gave recoveries in the range 95 to 98%.

REFERENCES: [1] [2]

Arthur D. Little, Inc., Backup Data Report prepared under NIOSH Contract 200-82-2528 (unpublished, October 7, 1983). Thrun, K., J. Harris, and V. Grady. "Sampling and Analysis Procedures for Pesticide Manufacturing Wastes," Report, EPA Contract No. 68-02-3111 (1982).

METHOD WRITTEN BY: K. T. Menzies, K. J. Beltis, A. C. Roche, Arthur D. Little, Inc.; and B. R. Belinky, NIOSH/DPSE.

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