Credibility in the TLV Process
The Castleman and Ziem paper (1988) on threshold-limit values [TLV] is a good analysis. It may be surprising to many professionals who use the threshold-limit values and do not question how they are determined. Yet the findings should not be unexpected when one considers that so highly complex and controversial a task should be entrusted to a voluntary, somewhat self-perpetuating body without oversight by any public or other disinterested agency.
At the same time, we should acknowledge the pioneer work of the TLV Committee of ACGIH at a time when there were practically no standards. Although we may quibble with many of the standards, their achievement in many work sites in this country and in other countries would be a great improvement over existing conditions.
One thinks of possible ways in which the credibility of the process can be assured. The authors suggest an international approach. Certainly this is desirable. Perhaps WHO or ILO should be entrusted with this function. In the United States, at least, industrial chemicals might be controlled in a manner similar to the Food and Drug Administration control of drugs. EPA already has responsibility for large areas of the problem: pesticides and other contaminants in water, air, soil. Why not a joint mechanism of EPA-OSHA-NIOSH-FDA, with the National Academy of Sciences providing oversight?
But whatever the mechanism, there will be little progress unless basic scientific research, particularly for chronic effects, is more adequately supported than at present. Otherwise, we will continue to rely unduly on corporate data and on the experience of human casualties.