Page:NIOSH Manual of Analytical Methods - 9201.pdf/1

 CHLORINATED AND ORGANONITROGEN HERBICIDES (PATCH)

ANALYTES: Figure 1 FORMULA: Table 1 METHOD: 9201, Issue 1

MW: Table 1

CAS: Table 1

EVALUATION: PARTIAL

OSHA: Table 1 NIOSH: Table 1 ACGIH: Table 1

PROPERTIES:

NAMES:

Alachlor Cyanazine

Atrazine Metolachlor

PASSIVE EXPOSURE:

SHIPMENT:

DERMAL PATCH (Polyurethane Foam [PUF] pads, 10 x 10-cm, 3 to 4 mm thick)

place pad in an aluminized card holder with 7.6-cm diameter circle cut in one side. Affix to worker’s clothing or skin. transfer pads to 120-mL wide-mouthed glass jars with PTFE-lined caps.

SAMPLE STABILITY:

at least 30 days at 4 °C [1]

BLANKS:

2 to 10 field blanks per set

RTECS: Table 1

Issue 1: 15 January 1998

Table 1

2,4-D acid 2,4-D, 2-ethylhexyl ester Simazine 2,4-D, 2-butoxyethyl ester

SAMPLING SAMPLER:

9201

MEASUREMENT TECHNIQUE:

GAS CHROMATOGRAPHY, ELECTRON CAPTURE DETECTOR, (GC/ECD)

ANALYTE:

Table 1

DESORPTION:

40 mL isopropanol diazomethane)

INJECTION VOLUME:

(containing

2 µL

TEMPERATURE-INJECTION: 270 C -DETECTOR: 300 C -COLUMN: 90 °C for 1 min; ramp to 160 °C at 35 °C/min; ramp to 200 °C at 5°C/min; ramp to 230 °C at 3 °C/min; hold 9 min. Total run time = 30 min. CARRIER GAS:

He, mL/min

COLUMN:

capillary, fused silica, 30 m X 0.25-mm ID, 0.25-µm film, 50% phenyl, 50% methyl silicone, DB-17 or equivalent. See Table 2

CALIBRATION:

standard solutions isopropanol

RANGE:

Table 3

ACCURACY

RANGE STUDIED:

not determined

BIAS:

not determined

OVERALL PRECISION ( ACCURACY:

rT

):

not determined not determined

of

herbicides

in

ESTIMATED LOD: Table 3 PRECISION ( r):

Table 3

APPLICABILITY:The working ranges are listed in Table 3. These cover from the LOQ to approximately 30X the LOQ [1]. This method may be applicable to the determination of many other thermally stable organonitrogen; aryl and alkyl acidic; and phenolic pesticides after evaluation for desorption efficiency, sample stability, and precision and accuracy. INTERFERENCES: Because of the great sensitivity of the ECD, there are many potential interferences. Among those observed are plasticizers (e.g., dibutyl phthalate), methylated fatty acids (give negative responses), phenols, and antioxidants and other additives (e.g., BHT), any volatile or semivolatile halogenated or nitrated organic, organophosphorous compounds, and other pesticides. Agricultural spray additives can presentserious interferences. Such additives include solvents, emulsifiers, wetting agents, breakdown products, and fertilizers (e.g., fatty acids and urea). Second-column confirmation is very desirable. Poorly precleaned pads and poor technique present significant interferences at low levels. These include phthalate plasticizers and PUF manufacturing additives and monomers. OTHER METHODS: Other patch methods allowing simultaneous analysis of organonitrogen and acid compounds and their esters are unknown.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition