Posted byESSI Posted in
Posted on Feb 07, 2017

Continuous Improvement feedback loops provide a framework in which expected results can be checked against actual and perceived success, informing decisions about future actions.  The Exposure Science & Sustainability Institute’s (ESSI) mission is to provide excellence in research and training in response to industry identified needs. The collaboration between ESSI, industry and the University of Minnesota’s Industrial Hygiene (IH) program provides a valuable feedback loop not only for ESSI but for our IH program and industry clients as well.

For example, one recent project was conducted to develop a more realistic estimate of a critical exposure model input, the contaminant generation rate. This research was motivated by a worst-case estimate for the emission of a chemical into the air resulting from use of a consumer product containing this chemical. The worst-case estimate was too conservative to provide meaningful exposure assessment results and a more refined estimate was needed. In response to the request from industry sponsors, the PI (Susan Arnold) and her team designed a chamber study to simulate the product’s use in a controlled environment to estimate an empirically derived generation rate based on the measured airborne chemical mass concentration.  The study created experiential opportunities for two master’s level students and one PhD candidate. These students gained first-hand experience preparing for and conducting a chamber study. They also observed and applied methods to address data quality and sample integrity, reconciled real-time and integrated sampling methods and conducted data analysis.  This evaporation rate was evaluated by conducting a similarly designed simulation study in an actual residence and comparing the measured and modeled airborne chemical concentrations. Ultimately, the study’s empirically derived generation rate was two orders of magnitude lower than the screening level worst-case estimate and the predicted airborne concentration based on this model input matched the measured airborne concentration with a reasonable degree of accuracy.

The study produced a significantly refined generation rate, providing the industry sponsors with a tool to generate more accurate exposure estimates and in turn, more robust work practice guidance. While the IH graduate students gained valuable experience, this research helped inform faculty about the practical knowledge and skills that prospective employers need and value. The request for this kind of research helps inform ESSI’s research agenda and guide our equipment purchasing decisions so that we have the capacity to conduct leading edge research.