Document oMa9LR2DDKyY6dBrgOZyErQ0o

VOLUNTEERS for INTERNATIONAL TECHNICAL ASSISTANCE, Inc. COLLEGE CAMPUS, SCHENECTADY, NEW YORK 12308 Tel. (518) 372-5696 Reference #1974211S Lead Test c-- February 25, 1971 Lead Industries Association 292 Madison Avenue New York, NY 10017 Gentlemen: Do you have any simple non-laboratory (standard?) methods of checking paint from houses for the presence of lead? The enclosed method is being studied for opinions on its suitabil ity. Would it check lead for all types of lead paint (including lead chromate, or litharge) as well as white lead? Very truly yours. A. C. Titus Volunteer Coordinator enc:Memo w/enc LIA-76846 Here's a simple test I copied out of a journal that hasn't been publisized too much that I know of. I only left out' some general remarks in the introduction and under the "dis cussion" section, so it's pretty much verbatim. As with the dipstick method, this test is controversial, but you'll see that unlike the dipstick test, this method was compared to results from a spectrographic test. The latter is considered reliable enough to be used as a standard, so, theoretically, this test, if done as described, should be an excellent screening device. I would appreciate any information you might have to the contrary or in support. LIA-76847 N 1001.01 I I Spot test for Lead in Paint - J.W. Sayre, D, J. Wilson (Introduction "A semiquantitative method suggested by Kaplan and Shaull (Kaplan, E. and Shaull, R.S. - Determination of lead in paint scrapings. Amer. J. Public Health, 51:65, 1961* ) 'j : while easier, still has the limitation of requiring technical ability, equipment and dan gerous chemicals. The method of testing herein proposed is simple,' inexpensive, and specific, and can be performed in the patient's home. It involves the precipitation of lead as an "insoluble black sulfide through the following reaction: Pb + NA2S -- PbS Method A solution of sodium sulfide of about 5 to 8% is prepared. This solution must be kept tightly covered to prevent loss of potency through hydrolysis, which releases volatile * H2S. It Is conveniently dispensed in 5 nil polyethylene squeeze dropper bottles. Sodium sulfide does not attack the surface of these bottles. A label, "Poison: Harmful to Eyes or If Swallowed" Is affixed. In this concentration there: is no skin irritation, but the char acteristic odor of H2S may persist on one's hands for a half-hour. While the total amount of sodium sulfide in this small bottle (25O to 400 mg) is of low potential toxicity, it should nonetheless be kept out of the reach of young children. ; The paint can be tested either "in situ" or as a full-thickness chip of paint removed from the surface of the wood or plaster. If testing is done "in situ", it Is essential that all layers of paint be exposed down to the bare surface by making a diagonal cut with a sharp penknife. If the paint is tested as a chip, a similar diagonal cut is needed so that all layers of paint may be wetted by the sodium sulfide solution. This is essential since the deeper, older layers of paint and particularly the primer coat may be the only ones which I contain lead. Paint which has been more recently applied is less likely to contain hazardous ;i amounts of lead. All layers should be Inspected carefully for a color change (Fig. 1). 1, \ "i i !1 r LIA-76848 ^Adequate lighting is-most..important for proper interpretation of the test, particularly when evaluating dark colored or soiled paints. At times a hand magnifying lense is very useful. ' v c ; ; - I;-,:' ' ; Sensitivity This is a qualitative reaction and the intensity of the color change varies directly with the amount of lead present. Over the past two years in a lead paint screening program ! ni in Rochester, over 200 homes have been inspected. When the sodium sulfide testing method was introduced, chips were taken to the laboratory and examined with both sodium sulfide and spectroscopic methods. A black color developed in specimens proven to contain between 10 and 25$ lead. However, quantitative determinations on specimens of paint composed of. many layers may not yield an accurate comparison, since all layers of paint are not neces C, sarily lead-containing. For this reason, a specimen of exterior white primer paint of known composition was obtained from a local paint manufactures. By calculation from the formula used in production, the paint contained approximately 22$ lead in the wet state. A specimen ii. I.fi was then dried and its lead content measured quantitatively. This resulted in a yield of 18$ lead. Assuming the value to be approximately 20$, the paint was diluted with another sample of white paint known to contain less than 1$ lead. Paint of successive dilutions was then applied to wood surfaces,, dried, and tested with the sodium sulfide solution. Small wooden samples were pieced together and a comparator block made (fig.2). It can be seen that grad ations of light grey through dark grey to black are obtained and that at the lowest dilution of 0.8$ a faint grey color is present. Colors at the 15 to 20$ range are dark enough to make i it difficult to approximate lead concentrations over this amount. Specificity A host of other heavy metals can be found in paints. Those found in large quantity are zinc, titanium, and barium, none of which form black sulfides. Other metals are constituents of pigments and occur in amounts less than 1$: cadmium, chromium, cobalt, iron, manganese, magnesium, mercury, molybdenum, and nickel.5 of these, black sulfides are formed by iron, nickel, mercury, and molybdenum but the quantities present are small enough to cause no confusion. t i\* v *- LIA-76849 f ' ' - pper also, forms a black sulfide, but Its only use ` in paint, is for its anti-fouling pro*~ i rties. It would have no place in house hold paints. Black paint may be difficult to in- irpret, but' is not ordinarily made with leSd. 5 Care must be taken, however, in testing ;tal surfaces covered with paint such as pipes, or radiators since the iron or copper may 1 i precipitated. .; Discussion Surveys made in a number of U.S. cities have demonstrated the prevalence of lead painted ousehold interiors to be as high as 50 to 70 nis method, however, when used as described he^in, puts testing within the reach of many eople such as public health nurses, community aids, and volunteers. A comparator block uch as shown in (fig.2) is easily made and could be used as a standard If extensive testing as planned. There are a number of other advantages offered by the sodium sulfide spot test: 1) The ethod Is simple. Inexpensive and involves a minimum of chemicals and equipment. The small Iropper bottle with its tightfitting cap is easily carried in one's pocket or the glove compartment of a car. The bottles can be obtained from most pharmacies. 2) Little training s needed in the interpretation of the color change. Care must be taken to test all layers if paint down to and including bare wood or plaster. 3) The testing can and should be done In ;he home, particularly in areas accessible to children. Attention should be paid to areas here children have been observed to pick at walls or windowsills. Loose chips of paint on the floor or on the ground outside should also be tested. 4) Testing may be done at the time surfaces are scraped and refinished. In several Instances in Rochester the house painter was shown how to do this. 5) The simplicity of performance and ease of interpretation has proven this spot test an adjunct to screening campaigns to identify early cases of lead poisoning. James W. Sayre, M.D. Department of Pediatrics \1 .: David J. Wilson, Phd., Department of Chemistry University of Rochester School of Dentistry 260 Crittendon Boulevard Rochester, New York 14620 ;i LIA-76850 Spectroscopic lead -analysis were performed by Luville .Steadman, Phd, Radiation Biology and Biophysics at the University of Rochester Department ; j. :i References I ! j I Chisolm, J.J., and Harrison, H.Hi : Theexposure of children to lead. Pediatrics, 18: 943, 1956. Barltrop, D., and Killala, N. J. P.: Factors influencing exposure of children to lead, arch. Dis. Child., 44: 476, 1969. Kaplan and Shaull, (details in text) : Thienes, C. H., and Haley, T. J. : Clinical Toxicology. Philadelphia: Lea and Febiger, 1964. Brown, R. A. : Personal communication.