Document 37L8GnmNk971bOykEdjw3nngD

OREGON STATE BOARD OF HEALTH STATE OFFICE BUILDING P.O. BOX 231 PORTLAND, OREGON 97207 TOM M eCALL GovERNOR December 24, 1970 MEMBERS OF THE BOARD A. V. JACKSON, D.O. President Forest Groove BEATRICE, K. ROSE, M.D. Vice President Port land c o n r a d n ., McCo n n e l l , R.ph. Second Vice President Port end EDWARp M. ANDERSON Eugene B. BRANDT BARTELS, M.D. Medf or d JOSEPH; E. BURNS Hermist on CHARLES S. CAMPBELL, M.D. Siem ROBERT 1. DAUGHERTY, M.D. Lebanon ARTHUR HUBER, D.M.D. Ast oria FREDERICK H. TORP Por t l and EDWARD PRESS, M.D. Por t l and Secret ary and State Healt h Off icer Robert A. Kehoe, M.D. Kettering Laboratory College of Medicine Cincinnati, Ohio 45219 . Dear Dr. Kehoe: We again have some problems concerning lead and come to you seeking advice. Our problem at the moment is pottery used for food preparation and serving, and the possibility of leaching lead from the glaze coating. The problem is really broader than that of lead and brings up potential problems with other toxic metals. For the moment, however, our questions concern lead. Our case in hand does not involve imported pottery but is that of domestic pottery manufactured by a small religious group for sale to the public. The group utilizes some commercial glazes and also procures raw materials for mixing their own glazes. The formulas they use are standard mixes taken from glazing manuals, and the firing is in the neighborhood of 2000F. The occurrence of several episodes of illness in this group over a period of time led to the request by our Epidemiology Section, that we evaluate their pottery making operations and use of such pottery. Several pieces of pottery were taken at random and filled with acidic acid at a pH of 3.1 and left at room temperature for 24 hours. The samples were then analyzed through the use of atomic absorption. The results can be seen in the first column of the attached table. After viewing the results we made contact with several persons in the pottery industry and eventually we were placed in touch with Mr. B. W. Merwin, Chairman of the Research Committee of 0015301 art A. Kehoe, M.D. cernber 24, 1970 age 2 the United States Potters Association. He indicated that the Potters Association has sponsored a vast amount of work in this area over the past 10 years; and that you were partly responsible for their entrance into this area. We obtained a copy of the ASTM method Mr. Merwin indicated, which in essence differed from ours in sample preparation. The ASTM method calls for a 5% acidic acid solution to be placed in the container for 30 minutes at 60C. The results of our analysis under these conditions, can be seen in column 2 of the attached Table. Utilizing the 7ppm limit for lead mentioned by Mr. Merwin, we see that there are no problems with this pottery. At the time we talked to Mr. Merwin, he indicated that Federal Food and Drug Administration was also involved in this field and may come up with standards that are slightly different from theirs. We have made some preliminary contacts with the Food and Drug personnel and find that the method being used in thp Seattle office calls for a 4% acidic acid solution to remain in contact with the pottery piece for 24 hour$. They also use a 7ppm limit for lead. We are confused by this apparent difference in standards and also confused by the rationale of the standards themselves. The short term application of a concentrated acid solution to a dinner plate or a dinner cup may be satisfactory in protecting the consuming public from lead ingestion, but what about a casserole or a dish that may be used for food storage? A casserole may be placed in an oven at an elevated temperature for three or four hours and a food storage dish may be placed in a refrigerated area for several days. In our own case, one of the dinner plates revealed a very high concentration of lead when left over night. When run by the method specified under ASTM the results came put to be rather low. While this meets the ASTM standard, is this a realistic standard if food storage is to be taken into consideration? At the moment our concern is not this particular group, but domestic pottery made by any number of small manufacturers. In the so-called hobby field, there are a good many who seem to want to collect these gayly colored utensils, not only for decorative purposes at home, but for use with food. Many of the persons involved in the manu facture may not, we believe, be sufficiently skilled in this area and this may constitute a significant threat to public health because of toxic metals involved. This brings up our other concern of the different metals utilized for colors, such as cadmium, selenium, zinc, and copper. I would assume that the same leaching method could be utilized for all of these materials if a standard time, concentration, and temperature can be agreed upon. However, the standards for each one should be different and we do not have standards for these materials at this time. Kir 0015? o jbert A. Kehoe, M.D. jecember 24, 1970 Page 3 1 have raised several questions that are perplexing to us. I hope that there are not so many that they will prevent you from commenting on them, since we would certainly appreciate your opinions on these matters. Sincerelv, Chief Industrial Hygiene Engineer Occupational Health Section DDD/cg KEr 0 0 1 5 3 0 3