Page:NIOSH Manual of Analytical Methods - 5002.pdf/1

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OSHA:	0.1 mg/m³
NIOSH:	0.1 mg/m³; Group I Pesticide
ACGIH:	0.1 mg/m³; STEL 0.3 mg/m³
PROPERTIES:	solid, MP 161 °C; VP not available

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SYNONYMS:

3-(α-acetonylbenzyl)-4-hydroxycoumarin.

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SAMPLING

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SAMPLER:	FILTER (1-µm PTFE membrane)
FLOW RATE:	1 to 4 L/min
VOL-MIN: VOL-MIN-MAX:	200 L @ 0.1 mg/m³ 1000 L
SHIPMENT:	routine
SAMPLE STABILITY:	93% recovery after 7 days @ 25 °C[1]
BLANKS:	2 to 10 field blanks per set
BULK SAMPLE:	desirable; 1 to 5 g

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ACCURACY

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RANGE STUDIED:	0.054 to 0.24 mg/m³[1] (408-L samples)
BIAS:	none identified[1]
OVERALL PRECISION (ŜrT):	0.056[1]
ACCURACY:	±11.0%

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MEASUREMENT

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TECHNIQUE:	HPLC, UV DETECTION
ANALYTE:	Warfarin
EXTRACTION:	5 mL methanol; swirl
INJECTION VOLUME:	20 µL
MOBILE PHASE:	30% of 0.0025 N phosphoric acid and 70% methanol, isocratic, 1.5 mL/min, ambient temperature
COLUMN:	C18 reverse phase, 10-µm packing, 25 to 30 cm
DETECTOR:	UV absorption @ 280 nm
CALIBRATION:	standard solutions of Warfarin in methanol
RANGE:	20 to 200 µg per sample
ESTIMATED LOD:	2.5 µg per sample
PRECISION (Sr):	0.016[1]

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APPLICABILITY: The working range is 0.05 to 0.5 mg/m³ for a 400-L air sample.

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INTERFERENCES: No interferences have been studied.

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OTHER METHODS: This is P&CAM 313^[2]⁠ in a new format. Analytical methods for Warfarin in some rodenticides^[3] and in drugs^[4] are available; these are spectrophotometric methods for bulk materials.

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

1. Backup Data Report, P&CAM 313, prepared under NIOSH Contract 210-76-0123 (unpublished, April, 1979).
2. NIOSH Manual of Analytical Methods, 2nd. ed., V. 6, P&CAM 313, U.S. Department of Health and Human Services, Publ. (NIOSH) 80-125 (1980).
3. Horwitz, W., Ed. Official Methods for Analysis of the AOAC, 13th ed., p. 85 (1980).
4. Ibid, 628.