There is a huge and changing number of chemicals in commerce for which workplace exposure criteria have not been assigned. Assigning an exposure criterion by an expert committee is resource-intensive - not soon available for the large majority of chemicals in current use. In the absence of assigned criteria, we have provided a regression method to estimate a first- screen estimate of a 'TLV/WEEL-equivalent' inhalation time-weighted average exposure criterion for a pure chemical (or chemical group) from a measure of a non-stochastic toxic exposure to elicit a chronic or sub-chronic health effect, known as a lowest observable adverse effect level (LOAEL) or a (highest) no observable adverse effect level (NOAEL). Results are presented for six data sets for which both a threshold limit value (TLV) or workplace environmental exposure level (WEEL) exposure criterion is presently assigned, and a LOAEL or NOAEL measure of toxic health effect was available from the United States Environmental Protection Agency Integrated Risk Information System data base. The results can be applied as a first estimate of exposure to substances for which no TLV or WEEL (TLV/WEEL) exists, and also serve as a mechanism for identifying substances for potential re-evaluation of their exposure limit, based on their relative position about the prediction models. (C) 2000 British Occupational Hygiene Society.
Whaley, D. A., Attfield, M. D., Bedillion, E. J., Walter, K. M., & Yi, Q. (2000). Regression method to estimate provisional TLV/WEEL-equivalents for non- carcinogens. Annals of Occupational Hygiene, 44(5), 361–374. https://doi.org/10.1016/S0003-4878(99)00108-8