2005 Progress Report: The Environmental Occurrence, Fate, and Ecotoxicity of Selective Serotonin Reuptake Inhibitors (SSRIs) in Aquatic Environments

EPA Grant Number: R829006
Title: The Environmental Occurrence, Fate, and Ecotoxicity of Selective Serotonin Reuptake Inhibitors (SSRIs) in Aquatic Environments
Investigators: Black, Marsha C. , Armbrust, Kevin L.
Institution: University of Georgia , Mississippi State University - Main Campus
Current Institution: University of Georgia
EPA Project Officer: Page, Angela
Project Period: September 1, 2001 through August 31, 2004 (Extended to April 30, 2007)
Project Period Covered by this Report: September 1, 2004 through August 31, 2005
Project Amount: $522,892
RFA: Drinking Water (2000) RFA Text |  Recipients Lists
Research Category: Drinking Water , Water Quality , Water


Pharmaceutical chemicals can enter aquatic environments after their prescribed use and lead to negative effects on aquatic organisms. For most pharmaceutical chemicals, the environmental fate and ecotoxicological characteristics are unknown. Of particular concern are drugs that are hormonally active because disruption of physiological processes in aquatic organisms can occur at low environmental concentrations. Selective serotonin reuptake inhibitors (SSRIs) are among the most commonly prescribed drugs. They are hormonally active, low concentrations have been shown to affect aquatic organisms, and there is evidence that they can be present in effluents from wastewater treatment plants. The objective of this research project is to characterize the occurrence, environmental fate, and ecotoxicity of five SSRI drugs (fluoxetine, fluvoxamine, paroxetine, citalopram, and sertraline) and their relevant metabolites. Investigations on the environmental chemistry of these five compounds will be used to identify the specific compounds that pose the greatest risk of becoming contaminants in aquatic ecosystems and their persistence in aquatic environments. Routine sampling of a wastewater treatment plant combined with market information on the numbers of prescriptions for specific SSRIs will be used to gauge the potential environmental exposure of specific compounds. Acute and chronic toxicity testing with Ceriodaphnia dubia followed by determination of chronic effects on mosquitofish, Gambusia affinis,and the amphibians Xenopus laevis and Hyla chrysoscelis will help characterize the compounds’ effects on key components of aquatic ecosystems.

Progress Summary:

Environmental Fate Testing

Water/sediment degradation experiments for paroxetine and citalopram were conducted in irradiated water-sediment systems. Paroxetine was extracted by accelerated solvent extraction (ASE) from sediments. Extraction recoveries from sediments were 65-74 percent. Paroxetine remaining in water and sediment under light at day 1 was 46-47 percent compared to 66-75 percent in the dark, indicating that paroxetine degraded by sunlight. At day 30 of application, only 0.1-0.2 percent of paroxetine remained in water and 6.0-32.7 percent in sediment, suggesting that paroxetine partitioned to sediment with time and may be degraded in sediment based on the decreasing amounts of paroxetine measured in sediments.

Water-sediment degradation of citalopram also was tested following extraction by ASE from sediments. Extraction recoveries from sediments for citalopram were 85-86 percent. After citalopram treatment, the dissipation rates from the water phase under light conditions were identical to those in the dark, indicating that citalopram is stable to light in water. Although 9-13 percent of citalopram applied still remained in the creek water phase at day 30, only 0.2 percent remained in the pond water phase at the same day, showing higher adsorption capacity to pond sediment. Of the originally applied citalopram, 45-52 percent and 52-63 percent were detected in creek or pond sediment at days 1 and 30, respectively, indicating that citalopram rapidly adsorbed to both sediments and was stable in the sediments.

Methods for the determination of five SSRIs in environmental water samples were developed using solid phase extraction and liquid chromatography/tandem mass spectrometry. Water samples collected from a major river downstream and upstream, as well as influent and effluent from a wastewater treatment plant, were collected between September 2004 to October 2005, and analyzed. Recovery tests were conducted at levels of

Future Activities:

In the next year, the investigators plan to:

  • Conduct patient surveys of SSRI drugs prescribed in Starkville, Mississippi, in an attempt to correlate the amounts of SSRI drugs prescribed with their appearance in wastewaters.
  • Examine histologically fish tissues from chronic exposures conducted in 2003 and 2004 to determine if external morphological indicators of delayed sexual maturity correlate with similar delays in gonad maturation.
  • Conduct additional exposures of X. laevis with fluoxetine and sertraline to include endpoints previously described, along with measurements of thyroid hormones (T3 and T4).

Journal Articles on this Report : 3 Displayed | Download in RIS Format

Other project views: All 44 publications 11 publications in selected types All 9 journal articles
Type Citation Project Document Sources
Journal Article Kwon J-W, Armbrust KL. Photo-isomerization of fluvoxamine in aqueous solutions. Journal of Pharmaceutical and Biomedical Analysis 2005;37(4):643-648. R829006 (2004)
R829006 (2005)
R829006 (Final)
  • Abstract from PubMed
  • Journal Article Kwon J-W, Armbrust KL. Degradation of citalopram by simulated sunlight. Environmental Toxicology and Chemistry 2005;24(7):1618-1623. R829006 (2005)
    R829006 (Final)
  • Abstract from PubMed
  • Journal Article Metcalfe CD, Miao X-S, Koenig BG, Struger J. Distribution of acidic and neutral drugs in surface waters near sewage treatment plants in the lower Great Lakes, Canada. Environmental Toxicology and Chemistry 2003;22(12):2881-2889. R829006 (2005)
  • Abstract from PubMed
  • Supplemental Keywords:

    pharmaceuticals, aquatic persistence, reproductive toxicity, developmental toxicity, thyroid,, RFA, Scientific Discipline, Waste, Water, Ecosystem Protection/Environmental Exposure & Risk, Ecology, Aquatic Ecosystems & Estuarine Research, Environmental Chemistry, Chemistry, Aquatic Ecosystem, Fate & Transport, Environmental Microbiology, Biochemistry, Ecology and Ecosystems, Drinking Water, ceriodaphnia dubia, fate and transport, pharmaceuticals, aquatic organisms, other - risk assessment, selective serotonin reuptake inhibitors (SSRIs), impact of pharmaceuticals, aquatic persistence, aquatic ecosystems, gambusia holbrooki

    Relevant Websites:

    http://www.mscl.msstate.edu Exit
    http://www.uga.edu/ehs Exit

    Progress and Final Reports:

    Original Abstract
  • 2002 Progress Report
  • 2003 Progress Report
  • 2004 Progress Report
  • 2006 Progress Report
  • Final Report