Document re5gdyNoxwz4kwD2yBakG3mGG

J. B. LYMAN MAR. LAB CC: F, W. Coster - Mar. Lab P. B. Wills - Mar. Lab J. L. Murray - Chicago rQiSiCrC**? A. L Dade T. R. Matthews B- Haskell f) C April 20, 1976 f 6^P- ,, c,~ CALCINED METALLIC OXIDE PIGMENT /TsCi/ (&***? We have had several inquiries as to whether nickel J chrrtf antimony titanate and chromium antimony titanate pigments (such i&4 as W-629 and W-694for example) can be safely used as replace- V . ments for lead or zinc chromate pigments. Both are currently used but in relatively small quantities. t 5* Toxicity data supplied by Shepherd Chemical, Siegle & Company, and Hercules has not been very useful. Siegle's statement that hot water extraction did not yield any hexavalent chromium proves nothing. I doubt that lead chromate would yield //U/ D(C much hexavalent chromium under similar test conditions. Haskell Lab has conducted a search and found nothing on the carcinogenic activity of these pigments. (However, the National Cancer Institute reportedly is testing nickel titanate.) An Ames mutagen test is not appropriate for heavy metals. An implantation study could be conducted but this would be expensive and of questionable validity. At the moment, it appears that the only way to determine the carcinogenic potential of these pigments is by a 2 year exposure study in animals. This would take nearly 3 years to complete and cost $200-300,000. Perhaps the pigment manufacturers could be persuaded to jointly sponsor such a test. In the meantime, we can only say that no evidence of carcinogenic activity has been found. Good industrial hygiene practices should be observed in handling these pigments. EES/bjr E. B. SWAIN P.S. to B. C. McKusick ~ Haskell Lab Do you see any need for restricting our usage of these and similar pigments? If so, please let me know promptly. C/l*. RECEIVED APR 2 i 1976 HASKELL LAS. DUP050077585