The Influence of Amphiphilic Molecules on the Environmental Fate and Transport of PharmaceuticalsEPA Grant Number: R829005
Title: The Influence of Amphiphilic Molecules on the Environmental Fate and Transport of Pharmaceuticals
Investigators: Kibbey, Tohren C.G. , Sabatini, David A.
Institution: University of Oklahoma
EPA Project Officer: Page, Angela
Project Period: September 1, 2001 through August 31, 2004 (Extended to August 31, 2005)
Project Amount: $316,600
RFA: Drinking Water (2000) RFA Text | Recipients Lists
Research Category: Drinking Water , Water Quality , Water
Thousands of tons of pharmaceuticals are produced annually for human and animal use, and significant quantities ultimately find their way into the environment. A wide range of pharmaceuticals have been identified in the environment, including antibiotics, analgesics, psychiatric drugs, and natural and synthetic hormones. Human pharmaceuticals enter the environment through incomplete wastewater treatment of drugs either not absorbed by the body or intentionally discarded down the drain. Pharmaceuticals in animal wastes enter the environment directly though infiltration into groundwater or runoff into surface waters. Although the concentrations of pharmaceuticals identified in the environment are typically low, the potential for long term risks to human and ecological health are increasingly being recognized.
This work will evaluate transport processes affecting pharmaceutical movement in the environment, and will study the influence of amphiphiles (e.g., surfactants, phospholipids) on the fate and transport of pharmaceuticals in the environment. Amphiphiles are widely used in pharmaceutical products to stabilize emulsions and enhance drug delivery within the body. In addition, surfactants from detergents and other products are often present in wastewaters, and enter the environment with pharmaceuticals through wastewater discharges. Because of their surface active nature, amphiphiles can have a profound effect on the fate and transport of many contaminants. It is highly likely that the same will be true of their effects on the fate and transport of pharmaceuticals.
This work will examine the influence of amphiphiles on the fate and transport of pharmaceuticals through a combination of batch and column adsorption and desorption experiments involving environmentally relevant pharmaceuticals and amphiphiles. Pharmaceuticals and amphiphiles will be used in concentrations covering the range of likely environmental conditions, from ultra-low concentrations (ng/L) of each, through moderate concentrations (mg/L or higher) which might be observed directly at an infiltration source (e.g., a confined animal feeding operation, etc.). Experimental results will be coupled with transport simulation (tracking both surfactants and pharmaceuticals) to assess the potential impact of amphiphiles on the migration of pharmaceuticals.
The results of this work will provide new insight into the fate and transport of pharmaceuticals. Although amphiphiles are widely used with pharmaceuticals and are present at high concentrations in wastewaters, work examining the influence of amphiphiles on the fate and transport of pharmaceuticals has not been reported to date. The results of this work will provide new quantitative tools for evaluating the transport of pharmaceuticals, and may ultimately lead to reformulation of amphiphiles used in drug delivery to reduce the environmental mobility of pharmaceuticals, enhancing opportunities for natural degradation.