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 ARSENIC, organo-: METHOD 5022, Issue 2, dated 15 August 1994 - Page 4 of 6 12.

Identify the component peaks. Measure peak height or area.

CALCULATIONS: 13. 14.

From the calibration graphs, calculate the amount (µg) of arsenic for each species in the sample (W) and in the average media blank (B). Calculate the arsenic concentrations, C, (mg/m 3) in the air volume sampled, V (L):

EVALUATION OF METHOD: The measurement precision obtained under the conditions recommended in this procedure is presented in Table 1 [1]. The overall precision of the method was tested using filters loaded in a dynamic aerosol generation/sampling system with particulates of the three organoarsenical compounds. The concentration levels tested for each species were 5, 10, and 20 µg As/m 3 of air. Depending on the concentration and species, the relative standard deviation ranged from 14.4% at the lowest level to 4.7% at the highest level. The collection efficiency of the method for organoarsenicals in the range of 5 to 20 µg/m 3 using a 300-L sample was found to be >99%. The collection efficiency of the method for inorganic arsenic was not determined. The accuracy of the overall method was determined by analyzing additional aerosol samples from each set using Neutron Activation (NAA) and X-ray Fluorescence (XRF) analyses. Since NAA and XRF techniques provide only the total elemental arsenic, the total arsenic obtained from the IC-AAS analysis was used for comparison. The accuracy ranged from 90 to 120% of the values obtained by NAA and XRF.

REFERENCES: [1]

[2] [3]

Colovos, G., N. Hester, G. Ricci, and L. Shepard: "Development of a Method for the Determination of Organoarsenicals in Air," NIOSH Contract #210-77-0134, available through National Technical Information Service, Springfield, VA 22161 as Order No. PB83-180794. NIOSH Manual of Analytical Methods, 2nd. ed., V. 6, P&CAM 320, U.S. Department of Health and Human Services, Publ. (NIOSH) 80-125 (1980). The Merck Index, 11th ed., Merck & Co., Rahway, NJ (1989).

METHOD REVISED BY: Mary Ellen Cassinelli, NIOSH/DPSE; P&CAM 320 originally developed under NIOSH Contract 210-77-0134.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94