Page:NIOSH Manual of Analytical Methods - 5006.pdf/1

 CARBARYL

C10 H7OC(=O)NHCH3

MW: 201.22

METHOD: 5006, Issue 2

5006

CAS: 63-25-2

RTECS: FC5950000

EVALUATION: FULL

OSHA : 5 mg/m 3 NIOSH: 5 mg/m 3; Group II Pesticide ACGIH: 5 mg/m 3

PROPERTIES:

Issue 1: 15 May 1985 Issue 2: 15 August 1994

solid; crystal; d 1.230 g/mL @ 20 °C; BP decomposes; MP 142 °C; VP <0.005 Pa (<4 x 10-5 mm Hg; <0.4 mg/m 3) @ 20 °C

SYNONYMS: Sevin; 1-naphthalenol N-methylcarbamate; 1-Naphthyl-N-methylcarbamate

SAMPLING

MEASUREMENT

SAMPLER:

FILTER (glass fiber)

TECHNIQUE:

VISIBLE ABSORPTION SPECTROPHOTOMETRY

FLOW RATE:

1 to 3 L/min

ANALYTE:

p-nitrobenzenediazonium tetrafluoroborate complex

VOL-MIN: -MAX:

20 L @ 5 mg/m 3 400 L

SAMPLE WORKUP:

SHIPMENT:

ship filters in 25-mL scintillation vials

20 mL 0.1 M methanolic potassium hydroxide; to 2-mL aliquot, add 17 mL glacial acetic acid; add 1 mL p-nitrobenzenediazonium tetrafluorobate

WAVELENGTH:

475 nm

CALIBRATION:

Carbaryl in methylene chloride

RANGE:

0.1 to 1.0 mg per sample [2]

ESTIMATED LOD:

0.03 mg per sample [3,4]

PRECISION (Sr):

0.015 [1]

SAMPLE STABILITY: BLANKS:

at least 7 days @ 25 °C [1] 2 to 10 field blanks per set

ACCURACY RANGE STUDIED:

2 to 13 mg/m 3 [1] (90-L samples)

BIAS:

- 0.73%

ˆ rT): 0.057 [1] OVERALL PRECISION (S ACCURACY:

± 11.3%

APPLICABILITY: The working range is 0.5 to 20 mg/m 3 for a 200-L air sample.

INTERFERENCES: Phenols such as 1-naphthol will give a positive interference [2]. Interferences from other aromatic carbamates and phenoxyacetic acid pesticides may occur but have not been documented.

OTHER METHODS: This revises Method S273 [2].

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