Page:NIOSH Manual of Analytical Methods - 5601.pdf/5

 ORGANONITROGEN PESTICIDES: METHOD 5601, Issue 1, dated 15 January 1998 - Page 5 of 21 UV or Mass Spectra. Confirmation may be achieved through comparison of unknown spectra with reference spectra where available. Relative response ratios (See Table 10 for ratio of absorbances at 225 nm/200 nm for selected analytes) will give a moderate level of confirmation. Some analytes (O-aryl carbamates especially) can be confirmed by GC/MS using highly deactivated injection ports and analytical GC columns, or by HPLC/MS.

EVALUATION OF METHOD: This method was evaluated over the ranges specified in Table 2 at 25 °C with 240-L air samples. Samplers were tested at 15 and 80% relative humidity and 10 and 30 °C. In these experiments, test atmospheres were not generated; instead, analytes were fortified on the face of the sampler filters. The conditioned air was pulled through the samplers at 1 L/min for four hours. No significant difference in sampler performance was noted at any of these temperature/humidity combinations. Evaluation of sampler precision and stability was conducted at ambient conditions of temperature and relative humidity. Overall sampling and measurement precision, bias, accuracy, and average percent recovery after long-term storage are presented in Table 2. No breakthrough was detected with samplers fortified with 480 µg per analyte per tube after sampling eight hours at 1 L/min. For the estimation of LOD/LOQ, a series of media-spiked standards were prepared in triplicate, analyzed, and responses fitted to a quadratic curve. The Limit of Detection (LOD) and Limit of Quantitation (LOQ), given in Table 2, were estimated according to NIOSH SOP 018 [1, 17]. Criteria established by NIOSH were met [1]. REFERENCES: [1] Back-up Data Report [1995, unpublished] Carbamate, urea, and sulfenimide pesticides, prepared under NIOSH Contract 200-88-2618. [2] NIOSH [1977]. NIOSH Manual of Analytical Methods (NMAM), 2nd ed., v. 3, s273, U.S. Dept. Health, Education, and Welfare, National Institute for Occupational Safety and Health (NIOSH) Publ. 77-157-C. [3] NIOSH [1994]. Method 5006. In: Cassinelli ME, Ed. NIOSH Manual of Analytical Methods(NMAM),4th ed. Cincinnati, OH: National Institute for Occupational Safety and Health, DHHS (NIOSH) Publ. 94-113. [4] OSHA Methods 63 and 74, OSHA Analytical Methods Manual, Carcinogen and Pesticide Branch, OSHA Analytical Laboratory, Salt Lake City, UT. [5] OSHA Stopgap Methods for individual pesticides (Refer to by compound name), Carcinogen and Pesticide Branch, OSHA Analytical Laboratory, Salt Lake City, UT. [6] EPA [1986]. EPA Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air, US EPA, Publ. EPA/600/4-87/006. [7] Hill RH Jr., Arnold JE [1979]. A personal air sampler for pesticides. Arch Environ Contam Toxicol 8:621-628. [8] Dolan JW [1993]. LC troubleshooting. LC-GC11(7):500. [9] EPA [1988]. EPA Method 531.1, Rev. 3.0, Methods for the determination of organic compounds in drinking water, US EPA. Publ. EPA 600 4-88 039. [10] Chibia, Mikio, Doornbos F [1974]. Instability of benomyl in various conditions. Bulletin of Environ Contami Toxicol 11(3):273-274. [11] Calmon, Jean-Pierre, Sayag DR [1976]. Kinetics and mechanism of conversion of methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate (benomyl) to methyl 2-benzimidazolecarbamate (MBC). J Agric Food Chem 24(2):311-314. [12] C a l m o n , Jean-Pierre, Sayag DR [1993]. Instability of methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate (benomyl) in various solvents, Ibid. 426-428. [13] Dolan JW [1993]. LC troubleshooting. LC-GC11(12):858-860. [14] Dolan JW [1993]. LC troubleshooting. LC-GC11(6):412-314. [15] Dolan JW [1993]. LC troubleshooting. LC-GC12(4):298. [16] Gere DR [1993]. Column watch. LC-GC11(10):710-712. [17] Kennedy ER, Fischbach TJ, Song R, Eller PM, Schulman SA [1995]. Guidelines for air sampling and analytical method development and evaluation. Cincinnati, OH: National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 95-117:65-67. [18] NIOSH [1987]. In: Sweet, DV Ed.. Registry of Toxic Effects of Chemical Substances. National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 87-114. NIOSH Manual of Analytical Methods, Fourth Edition