2,4,5-T (5001)

by National Institute for Occupational Safety and Health

2,4,5-T
See 2,4-D (Method 5001) for Procedure

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OSHA:  

10 mg/m³ (2,4-D or 2,4,5-T)

NIOSH:  

10 mg/m³; Group I Pesticide

ACGIH:  

10 mg/m³

PROPERTIES:  

solid; MP 153 C (2,4,5-T); VP not significant

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SYNONYMS:  

2,4,5-T: (2,4,5-trichlorophenoxy)acetic acid; Esterone 245; Trioxone; Weedone

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SAMPLING

SAMPLER:  

FILTER
(glass fiber, binderless)

FLOW RATE:  

1 to 3 L/min

VOL-MIN:  

15 L @ 10 mg/m 3

-MAX:  

200 L

SHIPMENT:  

routine

SAMPLE STABILITY:  

at least 1 week @ 25 C

BLANKS:  

2 to 10 field blanks per set

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MEASUREMENT

TECHNIQUE:  

HPLC, UV DETECTION

ANALYTE:  

2,4,5-T anion

DESORPTION:  

15 mL CH3OH; stand 30 min

INJECTION VOLUME:  

50 μL

ELUENT:  

0.003 M NaClO ₄-0.001 M Na2B407

FLOW RATE:  

1.7 mL/min

DETECTOR:  

UV @ 289 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

ESTIMATED LOD:  

0.030 mg per filter [2]

PRECISION (Ŝ_r):  

0.025 [2]

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ACCURACY

RANGE STUDIED:  

5 to 20 mg/m³ [1,2]
(100-L samples)

BIAS:  

4.78%

OVERALL PRECISION (Ŝ_rT):  

0.053 (2,4,5-T) [2]

ACCURACY:  

± 14.2%

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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/m³ of either compound for a 100-L air sample.

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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.

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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.

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