Page:NIOSH Manual of Analytical Methods - 9205.pdf/1

 CAPTAN and THIOPHANATE-METHYL on Dermal Patch Thiophanate-Methyl: C12 H14 N4 O4 S2 Captan: C9 H8 Cl3 NO2 S METHOD: 9205, Issue 1 Captan OSHA: N/A NIOSH: N/A ACGIH: N/A

MW: 342.40 300.59

CAS: 23564-05-8 133-06-2

EVALUATION: PARTIAL Thiophanate-methyl N/A N/A N/A

9205

RTECS: BA3675000 GW5075000 Issue 1: 15 March 2003

PROPERTIES: Thiophanate-methyl: Colorless prisms, mp 181.5182.5°C, soluble in acetone, methanol, chloroform, acetonitrile, insoluble in water. Captan: Odorless crystals, mp 178°C, soluble in chloroform, practically insoluble in H2 O

NAMES & SYNONYMS: Thiophanate-Methyl: Topsin-M, [1,2-phenylenebis(iminocarbonothioyl)]bisdimethyl ester carbamic acid Captan: N-(trichloromethyl)thio-4-cyclohexene-1,2-dicarboximide, Captec SAMPLING SAMPLER:

PASSIVE EXPOSURE:

SHIPMENT:

MEASUREMENT TECHNIQUE:

HPLC, UV detector

ANALYTE:

Captan, Thiophanate-methyl

place patch in card holder with 7.6-cm diameter circle cut in one side. Affix to worker’s clothing or skin.

EXTRACTION:

30 mL 40% isopropanol:60% acetonitrile (V/V) w/ TEA-PO4 preservative.

transfer patch to 50-mL centrifuge tubes with caps. Ship cold.

INJECTION VOLUME:

DERMAL PATCH (Cleanroom wipe, 4" x 4")

SAMPLE STABILITY:

At least 28 days at 4°C.

BLANKS:

2 to 10 field blanks per set.

ACCURACY RANGE STUDIED:

Not determined

BIAS:

Not determined

5 µL

MOBILE PHASE:

A=2% n-propanol in water, 0.02 M TEAPO4, pH adjusted to 7.0 +/- 0.1 using phosphoric acid B=2% n-propanol in acetonitrile. Gradient from 20% B to 70% B (20 min.), decreasing to 20% B (2 min.), hold at 20% B (5 min.)

COLUMN:

reversed phase C-18, 4µm, 250 x 2.00 mm or equivalent.

DETECTOR:

UV @200 nm

CALIBRATION:

Solutions prepared in extract solvent

OVERALL PRECISION ( Ö r T ):

Not determined

RANGE:

Table 1

ACCURACY:

Not determined

ESTIMATED LOD:

Table 1

PRECISION ( þ r ):

Table 1

APPLICABILITY: This method was developed for the analysis of the two analytes listed above on a dermal patch sampler from orchard workers. (See Figure 1.) In addition, this method may be used to analyze other fungicides and pesticides that may be present as long as they are separated from the two analytes by the analytical conditions of the method. It may be necessary to make adjustments to the gradient conditions of the method to obtain the required separation. INTERFERENCES: The potential interferences include other organic compounds, in particular other pesticides or fungicides that have the same retention time on a C18 column. Positive identification may be confirmed by dual column chromatography using an appropriate alternative LC column. Possible interferences include: ziram, myclobutanil, mancozeb, imidacloprid, and phosmet. OTHER METHODS: This method was developed in conjunction with method NMAM 5606, Thiophanate-methyl in air, and NMAM 9202, Captan and Thiophanate-methyl in handrnise.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition