A US analysis found influential chemical exposure limits developed by the American Conference of Governmental Industrial Hygienists (ACGIH) were heavily influenced by the industries producing and using the chemicals. It found that for more than 1 in 6 substances relied heavily on corporate data that had never been independently verified. The authors found unpublished corporate communications were important in developing TLVs [Threshold Limit Values] for 104 substances; for 15 of these, the TLV documentation was based solely on such information. The paper notes: “Efforts to obtain written copies of this unpublished material were mostly unsuccessful. Case studies on the TLV Committee’s handling of lead and seven carcinogens illustrate various aspects of corporate influence and interaction with the committee. Corporate representatives listed officially as “consultants” since 1970 were given primary responsibility for developing TLVs on proprietary chemicals of the companies that employed them (Dow, DuPont).” It concludes “that an ongoing international effort is needed to develop scientifically based guidelines to replace the TLVs in a climate of openness and without manipulation by vested interests.”

BI Castleman and GE Ziem. Corporate influence on Threshold Limit Values, American Journal of Industrial Medicine, volume 13, issue 5, pages 531-559, 1988.