Document 50yBaLwBw0Q9LKpp22D3Rx74J

February 8, l?6l Jakes lb Kisssiar, Major, U.S.A.F. 1236 Kevin Drive Fairborn, Ohio Bear Major Ussier: lour letter quotes infona&ticn on Laurel Cerana stone potter1;;,-. A copy of our release is attached. e believe that only acid foods or foods left on the dishes for storage ill result in the release of excessive amounts of lead in the food. I suggest - 1} If the pottery has not faded at all inside the vessels as compared to outside, you have probably not leached signi ficant amounts of lead off the dishes. (Used for imraeoiate foe service of non-acid foods, the dishes would not bo expected to dissolve much lead.} 2) You might consult tdth hr. Robert A. Kehoc-, Director of the Kettering Laboratory of the University of Cincinnati a world renowned expert who is well avmro of the problems involved* Very truly yours, Howard L. Mitchell, M,L., Chief Bureau of Occupational Health t CEirh attachment cc: Dr. Kehoe Christine oiner-t, K.B. Medical Officer f< 000837a N9697 STATE OF CALIFORNIA D EPARTM EN T O F PUBLI C H EALTH 2131 BERKELEY WAY BERKELEY 4, CALIFORNIA MEMORANDUM TO: ALL LOCAL HEALTH OFFICERS FROM: Malcolm H. Merrill, M.D., Director State of California Department of Public Health SUBJECT: Request to stop sale of Laurel Company "Cerama Stone" colored dinnerware* October 31s I960 It has come to the attention of the California Department of Public Health that the yellow "Cerama Stone" dinnerware (dishes, bowls, etc) of the Laurel Pottery Manufacturing Compary, operated by Laurel Potteries of California, Incorporated, has caused two well-authenticated cases of adult lead intoxication due to the routine use of this dinnerware. Tests indicate that these dishes are a health hazard in use only when acid or alkaline foods are repeatedly eaten from them or when such foods are left in the dishes for storage and then consumed. Tests of the Laurel "Cerama Stone" (the trade name applied to their dull finish glaze product) dinnerware in our laboratory further show that all colors (except white) do, in fact, give up lead to acid liquids (e.g., vinegar) and foods (e.g., applesauce) in quantities which would be capable of causing lead poisoning. Although the Laurel Company has stopped manufacture and has invited retail outlets to return all colored Laurel "Cerama Stone" ware (C.O.D. "earthenware", ',23.00, CTWT release valuation) only relatively few retail outlets have to date stopped sale and returned the dishes. Laurel Company makes other dish ware, but only the "Cerama Stone" type (the biggest seller) is involved in this problem. We are therefore advising you that the colored laurel Company "Cerama Stone" ware constitutes a hazard to public health and under the general powers of the Director of Public Health, we ask that you make every effort to have the dishes presently in stores in your community removed from sale. Prompt action is requested since the manufacturer is now prepared to substitute dishes claimed to be safe in some colors so that delay in removing present stocks might lead to difficulty in identifying unsafe dishes. (These new glazes have not been tested in our laboratory) To date, all colored Laurel "Cerama Stone" dishes available for retail sale or for exchange for trading stamps should be considered potentially hazardous. We understand that in any jurisdiction one or two better stores and possibly trading stamp outlets may carry this pottery. So far, no persons in California have been reported to have been poisoned by use of these dishes. A public release of this information is planned concurrently with this notice. N9697.01 sMany local health departments received this notice on Friday, October 28. K et 0008330 Memo to All local Health Officers 2 October 31* I960 There is a relatively simple method of testing the glass on dishes for lead. In 1939 the National Bureau of Standards published a "tentative test for the solubility of lead in glazes" which has been commonly used in the industry to insure the safety of dish ware. Currently, the American Society of Testing Materials is considering the endorsement of essentially the same easy qualitative test as a standard. A copy of this proposed tentative test is attached for your information. In this test the liquid in a glaze subjected to this test has shown no black precipitate with hydrogen sulfide if the dissolved lead amounted to less than four parts per million. This absence of black precipitate is considered to indicate a satisfactory glaze. Black precipitation may occur from the presence of other metals, thereby requiring further analysis. However, in our laboratory all colors of Laurel "Cerama Stone" dinnerware (except white) have shown lead in excess of four parts per million. We do not know of any other dinnerware presenting this hazard although such a situation may exist, as it did some years ago with dishes of foreign manufacture. We would appreciate being informed of your action in this matter and of the names of all the places from which this colored Laurel "Cerama Stone" pottery is, or will be, removed. Attachment Malcolm H Merrill, II.Id Director of Public Health H 0 0 0 8 38 1 s TENTATIVE METHOD OF TEST FOR SOLUBILITY OF LEAD FROM GLAZE SURFACES This method of test covers the procedure for determining the lead extrac tion from glaze surfaces on exposure to organic acids, more specifically acetic acid. . Significance of Test: This is a simple procedure for plant control use. The test may give too high values for "lead" because .other metals, such as copper, bismuth, cadmium, tin, arsenic, antimony, or mercury which may also be present, are precipitated. The "dithizone method" ^ may be used as a more specific test for lead. The present test though, designed to simulate conditions in service, should be of use for plant control and development work. Test Specimens: Various glazed shapes may be used, e.g., fruit dishes, bowls, cups, etc. For more critical comparison a similar shape should be used so that the total surface contacted by the reagent during the test is nearly the same. A standard size cup is recommended. Standard Solutions: The standard solutions should be prepared by adding the correct amounts of chemically pure lead nitrate to a 5/ acetic acid solution^/t In many instances, it will be found to be more convenient to use white distilled vinegar which contains about 5/ acetic acid. Where this is done the white distilled vinegar shall be used also in preparing the standard solutions. Standards shall be prepared which contain 1/2, 1, 2, k, ana 8 parts of lead per million parts of reagent. To prepare the standards, dissolve 0.0128 grams of C. P. Pb(N0 ) in 500 cc of reagent and dilute to exact ly 1 liter. This solution will contain 8 ppm of Pb. 500 cc of this shall be saved as a standard solution of this concentration. The re maining 500 cc solution shall be diluted to 1 liter which produces a concentration of k ppm of lead. The dilution process shall be continued in-preparing the standard solutions containing 2, 1, and 1/2 ppm Pb in solution. ' (over) KZ 0008382 N9697.02 & ._L if*" ^ '. / XyV'w/" Uhi-*: { i 0 b ii&t k*o ft &l lb } ^--4^ V 4 `!ju 5-7^ "7 t.O' - 2- The standard solutions shall be subjected to the H^S precipitatic described under procedure. The color of the precipitated standai in light so it is necessary to prepare freshly precipitated stanc daily before each series of tests. The stability of these sample be improved by the addition of l/b% gelatin to the standard solui If the reagent after the test contains higher amounts of lead, ap portions shall be used in the colorimetric comparisons. Higher c tions of lead make comparison difficult or impossible. Procedure: A. 150 cc of the boiling reagent (5% acetic acid solution or wl . distilled vinegar) shall be poured into the standard cup or shape specimen and allowed vo cool for 1/2 hours. The reage then be placed in a Nessler tube. A brisk evolution of hyd: sulfide gas shall be passed through the reagent for 3 minut< coloration of the -reagent shall then be compared with the s' solution in Nessler tubes which have been subjected to the ; hydrogen sulfide treatment. A suitable colorimetric or tur' meter will greatly aid in making comparisons. The colorimetric comparisons shall be made as soon as possi after the precipitation of the test reagent and standard sc B. An alternate procedure involves the exposure of the test sj to the test reagent introduced and maintained at room tempt for a period of Zb hours. Reports: The report shall state the lead in ppm containgd in the test re; It shall further indicate the specific reagent-^ used, the spec: shape, and which of the test conditions (A) or (B) was employed 1/ Scott's Standard Methods of Chemical Analysis, N. H. Furman 5th Edition, Vol. I. p 521, D. Van Nostrand Co., Inc. 1939 2/ 3% acetic acid solution or white, distilled vinegar. It m be desirable in some cases to use other organic acids, e.g acid. The concentration of the organic acid used shall be k f 0008383