Student Research: Brian Zevenbergen
Asthma development in aluminum smelter workers has been attributed to fluoride exposures in the potroom environment. This work focused on the relationship between air and urinary fluoride concentrations to determine if urinary fluoride concentrations could be used as a reliable measure of an individuals dose. Data were collected on total particulate, fluoride particulate and hydrogen fluoride along with pre and post shift urinary fluoride samples. Total airborne fluoride levels were found to have a mean value of 4.1 mg/m3 and ranged between 0.3 to 10.2mg/m3. Post-shift urinary fluoride levels were found to have a mean value of 2.5mg/g creatinine and ranged from 0.56 to 9.87 mg/g creatinine. Post-shift urinary fluoride was not found to be significantly predicted by any of the airborne fluid measures nor was it associated with any work place modifying factors, such as shift or crew assignment. However, a small subgroup varied from the majority of the workers in that they did not use respiratory protection. Within this sub-grouping, post-shift urinary fluoride concentration was found to be strongly predicted by total fluoride exposure with pre-shift urinary fluoride concentration as a secondary modifier (r=0.998 n=7).