Document X8ojLg3ZO5Lm30Ywog1NJe45K

ETHYL CORPORATION INTER-OFFICE To Donald E. Johnson Address From Robert F. Cope, Jr. Address Subject Screening Method for Presence of Asbestos Date in Insulation Material Nov. 6, 1979 Two NIOSH employees, Walter S. Kim and Richard E. Kupel, developed a quick and inexpensive test to detect the presence of asbestos in bulk samples of insulation material. A copy was obtained and is attached for possible use in our indus trial hygiene program. It will be published soon in the AIHA Journal. It was developed to test for the presence of magnesium and iron in asbestos of such materials as spray on insulation and. ceiling tiles. The reagents applied in the test will change color in the presence of magnesium or iron which are in asbestos and this will indicate a fairly strong possibility that the material contains asbestos. NIOSH has conducted tests with this method and the follow ing are the results; from a total of 70 field samples tested, 52 (74%) were positive and 18 samples gave a false/positive value. ` The test was 100 percent accurate in 22 samples of materials which did not contain asbestos (reagents did not change color). No false negatives occurred in 200 sample tests. RFC:sbb Attach. cc: J.A. Jacoby W.F. Jordan P.E. Kennedy T. Harbourt T.W. Maples M.M. Monrose A. Mulholland B.P. Pancamo J.T. Rucker P.J. Sanders R.L. Smith G.L. Ter Haar L. Simpson FilerOper.(BR-Asbestos) Robert F. Cope, Jr. Industrial Hvgienist TH 002376 K? Test for Screening Asbestos w.*. I*>^- S,COPE AND APPLICATION 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 K2 test is simple'and can be readily used in the field to screen for the `"presence or absence of asbestos. II. PRINCIPLE The K? test is based upon the formation of color complexes with Mg+^ *-! >"and Fe-^.released from asbestos. The Mg** from chrysotile is complexed ' ' with p-nitrobenzcneazo-o-naphthol. The Fe+Z from crocidolite and amositej.1 s' complexed with 1, 10-phenanthrol ine. A positive test.is v- ideated by the"formation of colored complex for Mg+2 a*nnAd,/notr' cFe" , and . it indicates possible presence of asbestos. ' The lr test'is'a colorimetric spot test for Mg , and Fe+S and is not specific'for" asbestos. * The, bull^ample^ay .contain _Fe compounds other, than, asbestos.^ Without !*^^^T"~trcai'ing"he1 sampler's' in"the Procedure,'the color forming reagent isv;!*" added directly, to the sample. If red color iorms, Fe is present as an v: interference'and these samples can be washed with water prior to the '~Xr~- test to^eliminate.the interference. In the Kz test; plaster (CaS04) interference*jis^rembved from the sample prior to the Mg test. IVJ SENSITIVITY,"PRECISION. AND ACCURACY !:T^'w"`*'J'lMth the'igTycerin'e treatment the detection limit is about ,2 mg of l;!j|5*s****pure chrysotile"per test; -w~ _ ............ ...... :^^ From the'total of 70 various field samples tested, 52 samples or 74* were correctly identified by the K2 test as to whether asbestos was present or absent. Only 18 samples or 26% gave false positive reactions. The K2 test was 100% accurate in identifying 22 samples that did not con tain asbestos. The test results were verified using the transmission electron microscope. APPARATUS 1. Teflon dish 2. Microspatula or glass rod 3. Dropping plastic pipet 4. 15 ml disposable plastic beaker 5. 25 mm' si2e 0.8 ym membrane filter 6. 25 mm Swinnex filter holder and gasket 7. 10 ml disposable plastic syringe -k . r ETH 002377 . REAGENTS (Reagent Grade) 1. Phosphoric acid, concentrated. 2. ION sodium hydroxide - Dissovle 40 g of NaOH in 100 ml of water. 3. Mg Reagent - Dissolve 1 mg of p-nitrobenzeneazo-a-naphthol in *100 mL of 2 N NaOH. Age at least a day. This reagent is stable over a month. 4. Hydrofluoric.acid - Dilute 20 ml of HP with 20 mL of water. - ' v Add 0.6 mL of concentrated HC1. 5.' Fe Reagent - Dissolve 2 g of 1,10-phenanthroline in 50 mL of rL::: ethanol. . This reagent is stable over a month. 6. Glycerine, reagent grade. A. ; Magnesium Test ` a. Place a small portion of sample in a plastic beaker. b. Add 5 drops of glycerine and mix well with a spatula . c. Rinse spatula with a small amount of water into the . % beaker. ' `^^^`^"d^ Filter the'sample through the filtration assembly consist ^V;.. - vTiSg^.ing of syringe attached to the Swinnex filter holder ` ~ ^ loaded with a membrane filter and a gasket. e. Filter with minimum of 5 washings or about 50 mL of water. .... :? f. ' Transfer filter to a Teflon dish. Magnesium Test : . * If plaster is known to be absent, take a portion of sample about the size of a large pea and begin with Step 2. ETH 002378 - < . ,* > p >V KV * v* 3 t 2. Add a drop of Hjpo^ and mix well by grinding the sample with a spatula. ....-'A 3.:. Add 2 drops of 10 N NaOH and mix well. t ,. irz'^'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.~J No" color change with Mg Reagent indicates the absence of................. *chrysotile. Even though amosite contains magnesium, this test does not produce the blue color. The iron test would produce a positive reaction indicating the presence of . asbestos:'" ' '' 8. Check for Mg interference as in Section III if positive :. --.t. result is obtained. n'*y B. - Iron Test 1 1. Place a small portion of sample on a Teflon dish. . 2. Add a drop of HF solution and mix well. 'j'iSC. . . ... t -*. -*c r. 3. 'Add 5 drops of Fe Reagent and observe the development of ..-^^ L-red color. - t '''if -' '4. The red color indicates that amosite or crocidolite may be . ; j.i- f .# .`.'t.spif'i' *5T '' '^*75.TCheck for iron interference as in Section III. ` :t;S7=:.: _.. .. ' ---V'*4"' C^WNotes'5^^f-*-V^V-V`"' ' - r.- ' .......:r - ,,> " J .. * . : } ' ; - '-v^ - -- r . *" ~ - If both tests give negative responses there is a low probability y * '** . that any asbestos is present. Once the presence of magnesium and/or "C --- iron is Indicated, further analysis if needed is done in the lab oratory to confirm, identify the type, and quantitate the percentage ` of asbestos. '."t / * w,, ...* .<; n .-* . #* " -- - * * ' ' ETH 002379 4 VUI. REFERENCE ,,i-<i ii i n r -rr ., . ^ 1. ^.y.-rrr*-' Caution: Asbestos Dust. A scriptographic booklet by Channing L. Bete Co#> inc>f Greenfield, Hass. Prepared in cooperation with U.S. DHEW,PHS, CDC, National Institute for Occupational Safety and Health, Cincinnati, Ohio (1973). 2. Fritz Feigl: Spot Tests - In Inorganic Analysis. Translated by rr- Ralptf E. Oesper. 5th Edition. Elsevier Publishing Company, Amsterdam. (1958) p. 225-227. 3. Halter S. Kim, Oames W. Carter,- II, and Richard E. Kupel: Quick Screening Test for Asbestos (K* Test). U.S. DHEW, PHS, CDC, NIOSH, Cincinanti, Ohio. To be publsihed in AIHAJ. . !.VW...y. . ' -** *s.. ..wy * -- ' Walters. Kim : \........ ._ . ' ,, Richard E. Kupel *-- ; S~t 1 -- C F*/ - */ ^ * / / , U.S.: Department of Health, Education, and Welfare puBi^c Health Service^;' ; Center!for; Disease,.Control Nat1oha1i|Institute?for Occupational Safety and Health Vrf-.V Division of Physical Sciences and Engineering Measurement'Support Branch ; - ; ' * Cincinnati, Ohio 45226 . /v - **( -: i'lvSn V April' 1979.:^;^'; ?u . Jr.................... f i AXi-'- k i* ETH 002380