ABSTRACT
The biogeochemical cycling of uranium regulates its transport in the environment, and a mechanistic understanding of its transformation is essential to identify uranium reserves for industrial uses and to predict the subsurface transport of this environmental contaminant. Since its discovery in 1789, uranium was widely used as a colorant in the glass and ceramic industry (Strahan 2001), and it has found modern use as a high-yield energy source. The demonstration of controlled uranium fission in 1942 set the stage for massive uranium mining operations to support nuclear weapons programs and, later, the nuclear energy sector (Plant et al. 1999). After a global shift from nuclear proliferation to nuclear disarmament and years of poor waste disposal practices at nuclear facilities, research interests in uranium have more recently focused on understanding its mobility in the environment as an ecological and human health hazard (Blanchard et al. 1983; Riley et al. 1992). The adverse effects of uranium exposure have been observed in microorganisms (Carvajal et al. 2012; Fortin et al. 2004, 2007; Konopka et al. 2013; Tapia-Rodriguez et al. 2012; VanEngelen et al. 2010, 2011), macrofauna (Markich et al. 2000; Tran et al. 2004), and aquaculture (Trenfield et al. 2011), and the public health effects arising from ingestion of uranium and exposure to its radioactive decay products (e.g., radium) have been documented (Blanchard et al. 1983; Hirose and Fawell 2012). As governments recognize the benefits of shifting away from fossil fuel–based energy sources and look to nuclear energy as an attractive alternative, understanding the biogeochemical cycling of uranium is imperative to ensure safe production of nuclear energy and to minimize its adverse effects on the environment.
