Document 6bR4g2NQ84nOzd21rn8RVRe83

TEST FOR SCREENING ASBESTOS Walter S. Kim James W, Carter, II Richard E, Kupel- U.'S. DEPARTMENT OF HEALTH, EDUCATION, AMD WELFARE-' Public Health Service . Center for Disease Control National Institute for Occupational Safety and Health Division of Physical Sciences and Engineering Cincinnati, Ohio ^5226 October 1979 A 0001461 TEST FOR SCREENING ASBESTOS I. SCOPE AND APH,I CATION This colorimetric test is applicable to the detection of magnesium (II). and iron (II). from asbestos in bulk samples. These samples include sprayed on asbestos as well as ceiling tiles. The test is. simple and can be readily used in the field to screen for the presence or absence of asbestos. The amount.of the sample needed for the test is only about the size of a large pea. II. PRINCIPLE . The te^ is based upon the formation of jf.glor complexes with Mg and Fe released from asbestos.- The Mg +2^rom chrysotile is conplexed with p-n'i.trophenylazo-a-naphthol. The Fe' from crocldolite and ainosite is complexed with 1, 10-phenanthrolirie.^A positive+est is indicated by the formation of colored complex for Mg and/or Fe , and it indicates possible presence of asbestos. III. INTERFERENCES The test is a colorimetric spot teat for Mg+2.. and Fe-1-2 , and is not specific for asbestos. ' * A bulk sample may contain Mg and Fe compounds other than asbestos. Without treating the sample as in the Procedure, a few drops of color forming reagents, are added directly-to the sample. If either color forms, an interferring substance is present and the sample must be cleaned before the test is conducted to eliminate the interference. In this cleaning process, plaster, mineral wool, fiberglass, and soluble Mg and Fe compounds are removed before the screening test, preventing their interference. \ IV. SENSITIVITY, PRECISION, AND ACCURACY . A sample containing more than 1% asbestos gives a positive color reaction. . ... : \ .... A total of -198 various field samples were tested before the Acid Wash steps were added to the Iron Test procedure. Results arc listed be low: Results of the screening test without the Acid Wash. No. of Samples 7. of Total True Positive 79 0 False Positive 50 AO n. True Negative 69 35 False Negat: 0 0 A 0001462 Kith the Acid Hash, the following results'were obtained from 13 samples. Results of the screening test with the Acid Wash. No. of Samples X of Total True Positive 5 APPAUATUS u oo ! Foisc Positive 0 0 True Negative 8 . 62 False Negative 0 0 ;- 1. Teflon dish or white plastic plate . . 2. Plastic or glass rod 3. Dropping plastic pipet 4. 15 mL disposable plastic beaker 5. 25 am size 0.8 jmi mixed cellulose ester filter 6. 25 nun size polyvinyl chloride filter 7. 25 tarn Swinnex filter holder and gasket 8. 10 ml. disposable plastic syringe , KKAGF.NTS (Reagent Grade) 1. Phosphoric acid, concentrated. 2. 10 N sodium hydroxide - Dissolve 40 g of NaOH in 100 mb of water. 3. Mg Reagent - Dissolve 1 mg of p-nitrophenylazo-a-naphthol in 10Q mL of 2 N NaOH. Age at least a day. This reagent.is stable over a month. '4, Hydrofluoric acid - Dilute 20 ml. of HF with 20 mL of water. `Add 0..6 mL of concentrated IlCl. 5. Fe Reagent - Dissolve 2 g of 1,10-phenanthroline in 50 mL of ethanol. This reagent is stable over a month. 6. Giycerin, reagent grade. 7. Acetic acid, concentrated glacial. 8* Sulfuric acid, concentrated. 9. Double de-ionized water. , , A 0001463 vn. procedure ^ A, Magnesium Test ' 1. Add a few drops of Mg Reagent directly to the sample. If , blue color appears, wash the sample with glycerin before the test. Any sample containing plaster is also washed with glycerin. Glycerin Wash a. Place a .small portion of sample', about the sissc of a. large pea, in a plastic beaker. b. Add 5 drops of glycerin and mix well with a plastic rod or spatula. c. Rinse the plastic rod with a small amount of water into the beaker. ... d. Kilter the sample through the filtration assembly consist ing of a syringe attached to the Swinnex filter holder loaded with a mixed cellulose ester filter' and n gasket. I // c. Kilter with a minimum of 5 .washings or about 50 -mb of water. . Transfer the filter to a Teflon dish for the Magnesium test. . 2. Add a drop of H^PO^ and mix well by grinding the sample with a plastic rod. 3. Add 2 drops of 10 N NaOH and mix well. 4. Add 5 drops of Mg Reagent and stir briefly. Note any color change. 5. Add 5 more drops of Mg Reagent and observe the final color. 6. A blue color indicates that chrysotile may be present. 7. Samples giving a positive test may be sent to a laboratory for confirmation. If the magnesium test is negative, the sample must be tested for iron. B. Iron Test * 3,. Add few drops of Fe Reagent directly to the sample. If a red color appears, v?ash the sample with the acetic--sulfuric acid mixture before the test.- Samples containing fiberglass ou mineral wool are also washed with the acid mixture. A 0001464 Acid Wash 1. Place a small portion of the sample, about the size of a large pea, in a plastic beaker. t 2. Add 5 drops of concentrated acetic acid. * 3. Add 5 drops of concentrated sulfuric acid. 4. Mix well and ultrasonicate if available for 5 minutes. 5. Filter the sample through a polyvinyl chloride filter with a minimum of 5 washings or about .50 inL of water. 6., Transfer the filter to a Teflon dish t.id proceed with the Iron Test. . 2. Add a drop of 1IF solution and mix well. 3. Add 5 drops of Fe Reagent and observe the development of red color. 4. The red color indicates' that amosite or crocidolite may be present. ... C. Notes :: ' It both parts of the test give negative responses, there is a low probability that any asbestos is present. Once the presence of mag-, nesium and/or'iron is. indicated, further analysis, if. needed, is done in the laboratory to confirm, identify the'type,'and quantitate the. percentage of asbestos, VIII. REFERENCE ' 1. Caution:___Asbestos Dust.. A scriptographic booklet by Channing L. Bete Co., Inc., Greenfield, Mass. Prepared in cooperation with U.S. 1)HEW, PlIS, CDC, National Institute for Occupational Safety and Health, Cincinnati, Ohio (1973). 2. Frit2 Feigl: Spot Tests - In Inorganic Analysis. Translated by Ralph E. Oesper. 5th Edition. Elsevier Publishing Company, Amsterdam. (1958) p. 225-227. 3. Walter S. Kim, James W.* Carter, II, and Richard E. Kupel: Quid; Screening Test for Asbestos. U.S. PHEW, PUS, CDC, NIOSH, Cincinnati, Ohio. To bo published in AI11AJ. A 0001465 'INTEROFFICE CORRESPONDENCE subject: ^UPDATED''ASBESTOS'QUIcFTES'i- V ".- 5` ,1 Kt, .>. SfA date: December 18, 1979 office: FROM: Radnor J. M. Haas TO: J. R. Blackerby F. J. Cebula K. E. Eaton R. FIgueroa R. E. llammitt B. Hatfield C. Milburn G. W. Reed Andy Becker Doyle Stegall Duncan Marcus Hook Tulsa Yabucoa Dallas Sarnia Corpus Christ1 Toledo Chester Dallas Tiie NIOSH procedure for asbestos determination has been take this copy to your assigned chemist and mark old cc Call with any questions. dated. Please "outdated." JMHldhs 2/6 Attachment cc: D. Camin - Marcus Hook suN-jvao.t: 1 .i * r A 0001460