Nanotechnology is one of the fastest growing technologies. It is expected to become a trillion US dollar industry within the next decade. According to the British Standards Institution, the American Society for Testing Materials, and the Scientific Committee on Emerging and Newly-Identified Health Risks, engineered nanoparticles (ENPs) have a dimension between 1 to 100nm and poses unique physical and chemical properties compared to their larger counterparts. Due to these novel properties, a wide range of new industrial applications for ENPs have been developed including: drug delivery, medical devices, food, cosmetics, agriculture chemicals and inputs, water purification and decontamination as well a range of applications in electronics and materials science. The wide and expanding application of ENPs may result in their release into the aquatic environment with exposure to aquatic organisms posing a risk that remains poorly understood. For drug and agricultural applications, the attractiveness of ENPs is the greater bioactivity. While there are regulatory limits on the release of ENP components, there has yet to be modification of regulations taking into account the differences in the biological activity of ENPs compared to either their more common solid forms. There are few studies assessing the risk of ENPs in the aquatic environment. These studies suggest that ENPs are toxic to fish at least to some degree; this includes ENPs comprised of: carbon nanotubes, carbon spheres called fullerenes (C60) and metal oxide NPs of titania, silica, aluminum oxide, silver, gold and zinc oxide.