Grantee Research Project Results
2004 Progress Report: Pharmaceuticals and Antiseptics: Occurrence and Fate in Drinking Water, Sewage Treatment Facilities, and Coastal Waters
EPA Grant Number: R829004Title: Pharmaceuticals and Antiseptics: Occurrence and Fate in Drinking Water, Sewage Treatment Facilities, and Coastal Waters
Investigators: Roberts, A. Lynn , Bouwer, Edward J.
Institution: The Johns Hopkins University
EPA Project Officer: Page, Angela
Project Period: September 1, 2001 through August 31, 2004 (Extended to August 9, 2006)
Project Period Covered by this Report: September 1, 2003 through August 31, 2004
Project Amount: $524,890
RFA: Drinking Water (2000) RFA Text | Recipients Lists
Research Category: Drinking Water , Water Quality , Water
Objective:
Prior to initiating this research project, there was a paucity of information concerning the occurrence, ecotoxic risk, and fate of pharmaceuticals in U.S environmental systems. The objective of this research project is to redress critical aspects of this deficiency by providing an assessment of the prevalence of important pharmaceuticals and antiseptics in drinking water, sewage treatment plant (STP) influent and effluent, and receiving waters. The specific tasks that comprise this research project are:
(1) Compile data on pharmaceutical usage, probable environmental concentrations, and associated risk. Select target compounds based on resulting calculations of potential environmental concentrations and, where possible, environmental risk.
(2) Refine analytical methods for quantification of pharmaceuticals in sewage and drinking water samples using gas chromatography/mass spectrometry (GC/MS) techniques that can be adopted readily by others.
(3) Analyze concentrations of target pharmaceuticals in raw and finished drinking water samples from public utilities to relate removal efficiency to the employed treatment processes.
(4) Examine the adequacy of current wastewater treatment practices for reducing pharmaceutical emissions by analyzing influent and effluent samples.
(5) Examine the biodegradability of selected pharmaceuticals and antiseptics in simulated wastewater treatment systems and in real wastewater to examine the influence of interactions with cocontaminants on biodegradability at the low levels encountered in the environment.
(6) Conduct field studies to determine the vertical and longitudinal distributions of target pharmaceuticals and antiseptics in the Upper Chesapeake Bay to seek evidence of rapid natural attenuation.
Progress Summary:
This report covers the third year of a 3-year research project. A no-cost extension has been granted; the total project duration therefore will be 4 years. As described in our original proposal, the first 2 years primarily have been devoted to Tasks 1 and 2. Although in previous progress reports we reported that compilation of use and risk data (Task 1) was complete, we subsequently have discovered better and more complete databases that are allowing us to extend our prior calculations. Method refinement (Task 2) for a suite of compounds that can be determined by derivatization (followed by GC/MS with either electron impact or negative chemical ionization) is 75 percent complete, and we have applied these methods to the analysis of anticonvulsant drugs in STP influent and effluent. During the coming year, our efforts will focus on extending our methods to the analysis of additional pharmaceutical compounds and to conducting additional analyses of drinking water and wastewater samples.
A detailed usage and ecotoxicity database has been constructed for the highest volume brand name, generic, and hospital drugs in 1999, 2000, and 2002 (Task 1). When possible, a preliminary risk assessment has been performed to assess the potential for these “high use” pharmaceuticals to exert ecotoxic effects by comparing probable environmental concentrations to measured or predicted toxicity. Several additional potential analytes have been identified through this process, many of which do not seem to have been targeted by other investigators. The results should prove useful in focusing attention on existing pharmaceuticals most likely to be encountered at environmentally significant concentrations and that could pose ecotoxic risks.
A new multicompound derivatization method was developed using pentafluorobenzyl bromide and bis(trimethylsilyl)trifluoroacetamide (Task 2). This method allows for the analysis of 44 compounds from a single sample and provides great sensitivity and reproducibility for the target analytes. The method we have developed for acidic compounds is particularly robust in that it performs best in a water:organic solvent mixture, thus eliminating the need for drying of a solvent extract prior to derivatization or drying of the solid phase extraction (SPE) cartridge. The derivatization method can be applied readily to other laboratory systems in which SPE is not needed, such as to batch biodegradation experiments, wherein the derivatization is conducted prior to a solvent extraction step. The derivative formed also is quite stable and is not destroyed on contact with traces of water. The procedures we have developed can be used by many other researchers with access to GC/MS instruments. This should facilitate studies of pharmaceuticals as environmental contaminants by other research groups.
An SPE procedure also was developed and optimized to provide ultralow detection limits for the target compounds. The SPE procedure also proved to be robust, exhibiting little interference when extracting target pharmaceuticals and personal care products (PPCPs) in water containing high humic acid concentration. Our optimization experiments also validated the advantages associated with recently developed polymeric sorbents over traditional C18 cartridges.
Aerobic batch biodegradation (Task 5) experiments have shown that most of our target PPCPs are biodegradable at low concentrations. These experiments also have revealed that different microbial communities are capable of degrading PPCPs. Different initial concentrations had little effect on the biodegradability of our PPCPs. These results should prove useful in determining the fate of these PPCPs in the environment and in assessing the potential limitations associated with normal screening tests conducted with defined media.
Future Activities:
We will determine concentrations of target analytes in raw and finished drinking water samples obtained from public utilities in Baltimore, Maryland (Task 3). Removal efficiencies will be related to treatment processes.
The adequacy of current wastewater treatment practices for reducing emission of pharmaceuticals and a selected antiseptic will be examined by measuring their concentrations in an additional STP beyond the one where analysis has begun (Task 4). The diurnal and seasonal characteristics of pharmaceutical loading into STPs also will be studied using the Back River STP as a model.
We will conduct laboratory studies examining the removal of the selected pharmaceuticals in the presence of a selected antiseptic to investigate whether toxic and/or inhibitory effects introduced by interactions with antimicrobials could limit biodegradability in actual wastewater. Results obtained in “clean” microcosms will be compared to those obtained in actual STP waters (Task 5).
To investigate the natural attenuation of pharmaceuticals and antiseptics in coastal waters, analyses will be conducted of samples obtained from the Upper Chesapeake Bay (Task 6). Analytes will include constituents that are partially attenuated in STPs as well as those that appear recalcitrant. Efforts will be made to include analytes detected in STP effluent at or above predicted no-effect concentration values. The very low detection limits of the analytical methods already developed should provide good spatial resolution necessary for interpreting differences in contaminant distributions and assessing dilution from fresh water sources.
Journal Articles:
No journal articles submitted with this report: View all 20 publications for this projectSupplemental Keywords:
environmental engineering, environmental chemistry, groundwater, estuary, risk assessment, ecosystem protection, environmental exposure and risk, waste, water, drinking water, groundwater remediation,, RFA, Scientific Discipline, Water, Waste, Ecosystem Protection/Environmental Exposure & Risk, Wastewater, Environmental Chemistry, Fate & Transport, Analytical Chemistry, Monitoring/Modeling, Environmental Monitoring, Ecological Risk Assessment, Drinking Water, Environmental Engineering, Groundwater remediation, monitoring, fate and transport, exposure and effects, pharmaceuticals, exposure, other - risk assessment, wastewater treatment plants, chemical contaminants, personal care products, surface water, groundwater monitoring, treatment, analytical methods, water treatment, drinking water contaminants, effluents, anticeptics, sewage treatment plantsProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.