BIOACCUMULATION OF CONTAMINANTS IN MARKET-SIZE HYBRID STRIPED BASS GROWN IN RECLAIMED WATER

Reclaimed water is municipal water that has received at least secondary treatment and basic disinfection and is reused after leaving from a water resource recovery facility - WRRF (previously known as a wastewater treatment plant). The United States produces over 121 billion liters per day of which only 7-8% is reused. Although there is significant interest in reusing reclaimed water for aquaculture in United States, the Environmental Protection Agency does not have standards sets for aquaculture use. The current minimum standards that WRRFs have for secondary treatment in the United States are consistent with the guidelines set by the World Health Organization for the safe wastewater use for aquaculture. This means that the reclaimed water that United States produces may not need further treatment before used for aquaculture. The goal of this project was to develop a reliable sustainable aquaculture system by using reclaimed water at decommissioned wastewater treatment facilities in Kentucky. The specific objectives were: 1) to evaluate the production of hybrid striped bass using decommissioned tank and pond at two WRRFs, and 2) to biomonitor hybrid striped bass grown to market size in reclaimed water for contaminants.

The experiment was conducted at Frankfort Water Resource Recovery Facility (FWRRF) and Winchester Water Resource Recovery Facility (WWRRF). Phase I hybrid striped bass were grown for 4-months in a 135-m³ decommissioned sludge thickener tank at FWRRF which uses ozone for disinfection. These fish were transferred and grown to market size in a 0.8-ha decommissioned oxidation lagoon at WWRRF which uses UV for disinfection. Fish flesh were analyzed for 45 contaminants and trace elements. Mercury was determined in feed samples and water as well as in fish samples. From all the contaminants analyzed, only 8 were detected (Table 1). All the values were well below the FDA action limits and permissible limits in edible food in all samples.