Marie Noele Croteau David Walters Janet L. Miller Daniel J. Cain Christopher C. Fuller Brianna L. Henry 2020 <div class="article_abstract"><div class="container container_scaled-down"><div class="row"><div class="col-xs-12"><div id="abstractBox" class="article_abstract-content hlFld-Abstract"><p class="articleBody_abstractText">Little is known about the underlying mechanisms governing the bioaccumulation of uranium (U) in aquatic insects. We experimentally parameterized conditional rate constants for aqueous U uptake, dietary U uptake, and U elimination for the aquatic baetid mayfly<span>&nbsp;</span><i>Neocloeon triangulifer</i>. Results showed that this species accumulates U from both the surrounding water and diet, with waterborne uptake prevailing. Elevated dietary U concentrations decreased feeding rates, presumably by altering food palatability or impairing the mayfly’s digestive processes, or both. Nearly 90% of the accumulated U was eliminated within 24 h after the waterborne exposure ceased, reflecting the desorption of weakly bound U from the insect’s integument. To examine whether the experimentally derived rate constants for<span>&nbsp;</span><i>N. triangulifer</i><span>&nbsp;</span>could be generalized to baetid mayflies, mayfly U concentrations were predicted using the water chemistry and U measured in periphyton from springs in Grand Canyon (United States) and were compared to U concentrations in spring-dwelling mayflies. Predicted and observed mayfly U concentrations were in good agreement. Under the modeled site-specific conditions, waterborne U uptake accounted for 52–93% of the bioaccumulated U. U accumulation was limited in these wild populations due to a combination of factors including low concentrations of bioavailable dissolved U species, slow U uptake rates from food, and fast U elimination.</p></div></div></div></div></div> application/pdf 10.1021/acs.est.0c03372 en American Chemical Society Uranium bioaccumulation dynamics in the mayfly Neocloeon triangulifer and application to site-specific prediction article