This study was requested by the Local Medical Health Officer for the area that includes Trail when he heard of concerns expressed about rates of inflammatory bowel disease (IBD) and chronic renal disease (CRD) in Northport, Washington, which is located close to Trail along the Columbia River valley. The MHO had not received any similar complaints or queries from Trail residents or physicians. There were no scientifically established links between these groups of diseases and any particular environmental hazards at the time. The hypothesis was that if in fact there were increased rates of disease attributable to smelter-related metals, the effect should be strongest closest to the source. Therefore, the purpose of this study was to see whether there was evidence for increased rates of these diseases in the Trail population.
The analysis was conducted by the Epidemiology Section of the BC Ministry of Health and involved comparing rates of hospitalization and mortality in the Trail Local Health Area with those recorded in the Central Kootenay Health Region (CKHU) and in the entire Thompson-Okanagan-Kootenay Region (TOKR). This review and comparison of the available data for 1988-1993 found that rates of chronic renal disease in Trail were not different from those in the CKHU and TOKR, and that the hospitalization rates for IBD in Trail were significantly lower than those for residents in the broader regions. There were no deaths from IBD in Trail during the time period studied.
