Document OE1k0MDrxDJndyZ59qjrMVbkM

Wifi American Journal of Industrial Medicine 13:615 (1988) LETTER TO THE EDITOR Corporate Influence on Threshold Limit Values The paper by Castleman and Ziem [1988] is an interesting summary of the unsatisfactory way in which threshold limit values (TLVs) have been produced in the past, and it emphasizes the need for adequately funded government bodies to set new TLVs; for this purpose they must have full access to all available data. In the light of past experience, TLVs should be constantly updated as rapidly as new data become available. (This, of course, implies that TLVs could go up as well as down.) My experimental work on fiber pathogenicity produces information that is difficult to use in direct extrapolations to human TLVs. With fibers, which produce no immediate toxic effects, epidemiology is the only real tool that can be used, and this is always 20 years out of date, producing information on the effects of past exposures. J.M.G. Davis, ScD Head of Pathology, Institute of Occupational Medicine. Roxburgh Place, Edinburgh, U.K. REFERENCES Casileman Bl. Ziem GE (1988): Corporate influence on threshold limit values. Am J Ind Med 13:531559. 1988 Alan R. Llss, Inc. PLAINTIFFS EXHIBIT