Page:NIOSH Manual of Analytical Methods - 500124-D.pdf/1

 2,4-D

C8H6Cl2O3

MW: 221.04

METHOD: 5001, Issue 2

CAS: 94-75-7

Issue 1: 15 February 1984 Issue 2: 15 August 1994

PROPERTIES: solid; MP 138 °C; VP not significant

(2,4-dichlorophenoxy)acetic acid; hedonal; Trinoxol

SAMPLING SAMPLER:

RTECS: AG6825000

EVALUATION: FULL

OSHA : 10 mg/m 3 NIOSH: 10 mg/m 3 ACGIH: 10 mg/m 3

SYNONYMS: 2,4-D:

5001

FILTER (glass fiber, binderless)

MEASUREMENT TECHNIQUE:

HPLC, UV DETECTION

ANALYTE:

2,4-D anion

DESORPTION:

15 mL CH 3OH; stand 30 min

INJECTION VOLUME:

50 µL

ELUENT:

0.001 M NaClO 4-0.001 M Na 2B40 7

FLOW RATE: 1 to 3 L/min VOL-MIN: -MAX:

15 L @ 10 mg/m 3 200 L

SHIPMENT:

routine

SAMPLE STABILITY:

at least 1 week @ 25 °C

FLOW RATE:

1.7 mL/min

BLANKS:

2 to 10 field blanks per set

DETECTOR:

UV @ 284 nm

COLUMN:

stainless steel, 50 cm x 2-mm ID, packed with Zipax SAX (DuPont) ambient temperature; 6900 kPa (1000 psi)

CALIBRATION:

solutions of analyte in methanol

RANGE:

0.15 to 2 mg per filter

ACCURACY RANGE STUDIED: BIAS:

5 to 20 mg/m 3 [1,2] (100-L samples) - 1.26%

ESTIMATED LOD: 0.015 mg per filter [1]

ˆ ): 0.051 (2,4-D) [1] OVERALL PRECISION (S rT ACCURACY:

± 10.21%

PRECISION (Sr):

0.01 [1]

APPLICABILITY: This method determines 2,4-D, 2,4,5-T, and their salts, but not their esters. The working range is 1.5 to 20 mg/m 3 of either compound for a 100-L air sample.

INTERFERENCES: High concentrations of esters of either compound do not interfere but require the use of a pre-column to prevent degradation of the HPLC column.

OTHER METHODS: This method combines and replaces Methods S279 [3] and S303 [3] which are the same except for eluent composition and UV detector wavelength.

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