Use of microbial and toxicant screening tests for priority site selection of degraded areas in water bodies

Abstract

In this study, a new approach has been taken to evaluate Saint John River water and sediment conditions. A battery of biochemical, microbiological and bioassay tests were used to identify degraded or degrading sediments and waters. Data were obtained from waters and sediments at 38 sites within the Saint John River Basin. The data suggested that the following four sites had the highest priority concern: Little River No. 34, Grand Bay, Saint John River near Boars Head No. 33, Madawaska River below mill No. 7 and St Francois-de-Madawaska, mill stream No. 2. The data also indicated that microbial population, biochemical or bioassay tests performed independently do not provide realistic evaluations of priority concern areas and that the “battery of tests” approach is necessary to provide additional information.