Lessons Learned from Trying to Set Guidance Values Using Human Studies

摘要

The research focus for occupational epidemiologists is safety. How can our study subjects work safely? Guidance values are established to protect employees and the general population(s). Examples of these environmental "exposures" can include uneven surfaces, physical exertion, repetition, temperature extremes, and contact with a chemical. Regulatory bodies use data from multiple disciplines to set a number, a guidance value, to inform protective practices and legal uses. Epidemiology studies, while well suited to evaluate human health and contribute to this process, often fall short in this risk assessment process. Several observations will be discussed. First, qualitative estimates such as low vs. high, and regression coefficients are not designed to test whether a unit value is protective. Second, exposure estimates are rarely harmonized across epidemiology studies, (i.e. using the same categories for low vs. high), or across disciplines (i.e. using dose in mg/kg/day vs. concentration in ug/l). Lastly, recommendations to improve the quality, reliability and validity of exposure data for risk assessment have been promulgated but not embraced by the epidemiology community due to feasibility, as one example. Before making additional recommendations, we first need to identify and resolve barriers to be successful in changing the status quo.