Meeting Abstract
Aquatic ecotoxicology has undergone vast growth in the understanding and modeling of the spatially and temporally dynamic nature of toxicants in fluvial aquatic systems (Corwin et al. 1997; Schindler et al. 1995). However, in classic laboratory toxicity tests used to define regulatory standards, organisms are subject to static exposures that use a set of highly controlled exposure conditions (Asifa et al. 2016; Santos Miron et al. 2004). Thus, contaminant effects resulting from static toxicity testing are disparate from the results of exposure conditions experienced by organisms in natural systems (Neal and Moore 2017; Harrigan and Moore 2017). The purpose of this study is to understand the effects of the structural characteristics (concentration, duration, and frequency) of temporally and spatially variant toxicant plumes on aquatic organisms to construct a realistic definition of exposure to apply to environmental assessment. Current research has not evaluated the effects caused by all exposure paradigm characteristics nor determined which characteristic or combination of characteristics causes the most detriment to organisms. This study used escape response of F. virilis crayfish from the predatory odor of M. salmoides following exposure to the herbicide, atrazine. Atrazine was delivered in pulses to flow through exposure arenas for a total of 47 hours while manipulating the concentration, frequency, and duration of the herbicide pulses. Escape response of crayfish was analyzed and resulted in treatment dependent reduction in olfactory response to predatory odor. These findings aid to elucidate the relative contribution of these characteristics of exposure to negative effects on organisms.
