Page:NIOSH Manual of Analytical Methods - 5606.pdf/1

 Rh

METHOD: 5606, Issue 1

OSHA: N/A

NIOSH: N/A

ACGIH: N/A

SYNONYMS: Topsin-M; [1,2-phenylenebis(iminocarbonothioyl)]bisdimethyl ester carbamic acid

SAMPLING

ACCURACY

MEASUREMENT

APPLICABILITY: This method was developed for the determination of thiophanate-methyl in air samples for a fungicide field study of orchard workers, and was meant to be used in conjunction with NMAM 5601 for the determination of carbendazim and captan as well. Recoveries of thiophanate-methyl may be lower when carbendazim, thiophanate-methyl, and captan are present in the same sample due to chemical interactions. The working range for this method is 0.025–5.67 ing/m³ based on a 100-L sample.

INTERFERENCES: Potential interferences to the analysis of thiophanate-methyl include other organic compounds, in particular other pesticides or fungicides that have the same retention time on a C-18 column. Positive identification may be confirmed by dual column chromatography using an appropriate alternative LC column. NOTE: It is possible to see a peak at the retention time for carbendazim, 9.8 minutes, since carbendazim is a decomposition product of thiophanate-methyl.

OTHER METHODS: This method is based in part on NMAM 5601 for the development work. As such, several of the compounds listed in NMAM 5601can also be analyzed in conjunction with thiophanate-methyl using this method.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition