Document oyLRR4mGMjDNn3nLz2VyypyX

May 12; 1959 cc : V. K. Rowe (2) Correspondence a?3.4-15-20^ Mr* W* E, McCormick, Director Department of industrial Hygiene and Toxicology The B* P. Goodrich Company 500 So* Main Street Akron l8> Ohio Dear Bill: ::v.YJ This Is in reply to your letter of May 4 Inquiring about the toxicological information we might have op vinyl chloride* Insofar as I am aware, there Is no good toxicological date, in the literature of the chronic toxicity of vinyl chloride, As . sV : ; you know, the Conference of Governmental Industrial Hygieniste has for some time been recommending a maximum average of 500 ppa../?'v This figure Is based upon the acute data of Patty, et al. and, hence, can not be relied upon to strongly when coi^THerlhg chronic exposures. Some years ago, we prepared a little writeup. assuming that this figure was alright and a copy of It is enclosed to show you what we have said* I have added my comments to it for your information. I should add that in the last month we have been Investigating vinyl chloride a bit and. find It to-be ' somewhat more toxic when given by repeated dally Inhalations but it Is too early yet to tell what vapor concentrations will be without adverse effect* We feel quite confident, however, that 500 ppm is going to produce rather appreciable injury when inhaled 7 hours a day, five days a week for an extended period. - As you can appreciate, this opinion Is not ready fordiBBealnation-. yet and I would appreciate it if you would hold it In confidence 3 but use it as you see fit In your own operations. When more data becomes available, I will try to remember to pass ..It on to you, Best regards. Sincerely yours. y. K, Rowe Biochemical Research laboratory 12-534 Building yKR/vmV: