Document JOYgYEjVO0d3X8reBEB1NGv

1 COMMERCIAL PRODUCTS HIGHWAY SIGN S ARCHITECTURAL PRODUCTS ADVERTISIN G IDEN TIFICATION SIGNS CALIFORNIA METAL ENAMELING COMPANY 6 9 0 4 EAST SLA U SO N A V EN U E LO S A N G EL ES 2 2, C A L I F O R N I A RA Y M O N D 3 - 6 3 5 1 January 25, 1963 Dr. Robert A. Kehoe University of Cincinnati The Kettering Laboratory College of Medicine - Eden Avenue Cincinnati 19, Ohio Dear Dr. Kehoe: V/e wish to thank you for your letter of January 23, 1963, regarding the ceramic glazefs to be used in aluminum cookware. Your thoughts on the matter are very much appreciated, as well as your carefully explained reasons for your answers to our questions. We are enclosing a copy of the California Test Method, which will explain their system for testing. We have checked the various colors proposed to be used in this program and find them to have a lead solubility of between two (2) and four (4) parts per million when tested with boiling acetic acid. Basically, the reason for the finish on the interior of the aluminum bowls is one of esthetics and saleability of the product. It is not in there for any engineering purpose per se. There are other porcelain finishes for aluminum which are lead free. It is our understanding, however, that the frits are generally composed of other types of heavy metals such as cadmium, and that these other metals might generally be as toxic as the lead used in the formulation proposed for the units in question. We have generally found that their resistance to acetic acid and citric acid are not as high as the lead bearing glazes proposed. We received a report from a Dr. Rutherford P. Johnstone, written by Mr. Edgar Littlefield. In this report, Mr. Littlefield suggested a test of *f8 hours of lemon juice and vinegar. In running this test the parts were carefully scrutinized to check the surface for any roughening or pitting, or any other change in texture or color. No such change was noted on a close examination of the parts. Mr. Littlefield stated that "If these full strength food acids do not affect the glaze, you can, in my opinion, consider the glaze to be safe.". Actually, these parts, being proposed, would not be used as a daily thing. This is a gift ware item, which would be used more for entertaining, generally speaking. K 0008345 N9689 / Dr. Robert A. Kehoe University of Cincinnati Page 2 January 25, 1963 We recognize the need for control of lead in products such as these, and do not wish to produce any article which would tend to be unsafe in use. These particular products, however, cannot achieve acceptance without the porcelain finish applied to the interior and if our glaze does not constitute a hazard, we would then propose to manufacture these parts under careful production controls. We would most certainly appreciate your comments relative to the above additional information. Very truly yours HVP:hb Enc. H. V. Penton President K 0008346 - **.it' RECEIVED TENTATIVE METHOD OF TEST FOB JAN 1 7 3ol SOLUBILITY OF LEAP F&UH > SAFETY DEPARTMENT SLA2E SUBFACES Scopa;: This method cf teat carers tha procedure for dotarsdjaing the lead extrac tion from glaze surfaces on exposure to organic acids, ore specifically acetic acid. Significance of Tost: Tins la a simple procedure .for plant control use. The test may give coo high values fr "lead" bec*.use other atetuls, such as copper, biav ch, cadmiu e , tin, nrssmic atifcijnony, ex- mercury winch tflay also he present, are precipitated, T/?.e "cithizoao rsethoti" ] / ms.? bs umd as a ore fty*aifit; le-st for lead. The present test though* lissigneci to isrulats co/tditiotts la service, ,..b::.'v. ba of run; for plant centre! d-rralopwiint work. Vif.rrauB .uinzi.-d shapes nay be used, a fruit, dishes, bowl*, cup, wfcr.-* For Eo.rif criticr.l comparison a similar sirap ehould be aaed so that the total b u t face contacted by the reegmne durins; the test is aaarly Ilia <,aae. A tandard size cap .is reoSBeded* Standard -Solutions; Ths standard aolui:oi;g shoyjl be * by ahriiny tno correct itfsounl.-r. of ohead. per* lead ait rate to a 11 ensile t?'.: eol^tioni/ t lx-, asruy o.&aiucs.iB, It will b* found to be mors convenient to use white ' :i is.;.: vaijegn:.- uhich cor loins about y>, acetic acid. Where tine is nose ths? shite hi Eft:;.lied vinegar shall on- used alec .1 prepaudu&g t&a atsiiurd no.lirtioB?'.. 1Sandercb- .dial \ ho prenu-re-i which coniair. 1/2, 1,. 2- , &n:l 8 parts of iod per llli.oii part c? retain:t.. To propers the st,idnrd#> dissolv c ,0.012b yr&xm .iff,. i-b PL/ICV}., 1 'ICO ec of i-eagwfcu and dilute to isK-r.* ly 1 lifiv-. 'bare aolhiioa. contain 8 v.,y*.s of Pu, %X> cc to' this nhti.li t b` u-.- i-.y e; - iCi:.<- hclUiiicr cf tlrji- concentre lion. 1T\* ra~ Ma.ih.ih.:; .S-00 cc ^oiuito;- shall be diluted to X liter which produces & concentre;;boo of '. ppm cf lend. The dilution process shall be costlasted in j r . t h e stniidurd solutions ccntBining 2, 1, ami 1/2 ppss Ft- in SCJ ut iCiC. !\vive.? ) # . gT 0008347 ^9689*^1 r The standard solutions shall be subjected to the H^S precipitation as described under procedure. The color of the precipitated standards fade in light so it is necessary to prepare freshly precipitated standards ' daily before each series of tests. The stability of these samples can be improved by the addition of l/k% gelatin to the standard solutions. If the reagent after the test contains higher amounts of lead, aliquot portions shall be used in the colorimetric comparisons. Higher concentra tions of lead make comparison difficult or impossible. Procedure : A. cc of the boiling reagent (5% acetic acid solution or white, distilled vinegar) shall be poured into the standard cup or other shape specimen and allowed to cool for 1/?. hours. The reagent shall then be placed in a Nessler tube. A brisk evolution of hydrogen sulfide gas shall be passed through the reagent for 3 minutes. Tne coloration of the reagent shall then be compared with the standard solution in Nessler tubes which have been subjected to the same hydrogen sulfide treatment. A suitable colorimetric or turbidi meter will greatly aid in making comparisons. The colorimetric comparisons shall be made as soon as possible after the precipitation of the test reagent and standard solutions. B. An alternate procedure involves the exposure of the test specimen to the test reagent introduced and maintained at room temperature for a period of 2^ hours. Henorts: The report shall state the- lead in ppm contained in the test reagent. It shall further indicate the specific reagent^ used, the specimen shape, and which of the test conditions (A) or (B) was employed. 1/ Scott's Standard Methods of Chemical Analysis, N. H. Furman, Editor 3th Edition, Vol. I. p 321 b. Van Nostrand Co., Inc. 1939 2/ 5% acetic acid solution or white, distilled vinegar. It may also be desirable In some cases to use other organic acids, e.g., citric acid. The concentration of the organic acid used shall be stated. K 0008348