Grantee Research Project Results
Final Report: An Integration of Copepod-Based BAFs, Lifecycle Toxicity Testing, and Endocrine Disruption Methodologies for Rapid Population-Level Risk Assessment of Persistent Bioaccumulative Toxicants
EPA Grant Number: GR832211Title: An Integration of Copepod-Based BAFs, Lifecycle Toxicity Testing, and Endocrine Disruption Methodologies for Rapid Population-Level Risk Assessment of Persistent Bioaccumulative Toxicants
Investigators: Chandler, G. Thomas , Ferguson, P. Lee
Institution: University of South Carolina at Columbia
EPA Project Officer: Hahn, Intaek
Project Period: May 16, 2005 through November 15, 2007
Project Amount: $298,907
RFA: Greater Research Opportunities: Persistent, Bioaccumulative Chemicals (2004) RFA Text | Recipients Lists
Research Category: Land and Waste Management , Safer Chemicals , Hazardous Waste/Remediation , Human Health
Objective:
The fundamental objective of this research was to develop a new integrated lifecycle toxicity testing system for persistent bioaccumulative toxicants that would provide concurrent data on PBT bioaccumulation, reproductive/endocrine level effects, and population-level impacts using meiobenthic copepods, 96-well microplate culture (per a new ASTM and OECD standard), and Leslie-matrix population growth modeling. We have focused on persistent halogenated compounds found commonly in coastal SC, and compared reproductive health and population growth across test copepod populations as a function of lipid-normalized body burdens (AFs); hence developing a Critical Body Residue approach for predicting how chronic PBT exposure will impact these ecologically-important microcrustaceans at the population maintenance level.
Approach:
Our research plan will address these objectives through a series of experiments designed to provide a holistic picture of persistent chlorinated pesticide bioaccumulation and endocrine/reproductive effects on model ecologically-important crustaceans in estuarine environments. These experiments will include laboratory egg-to-egg lifecycle toxicity tests with DDT, chlordane and lindane (singles & mixtures) at concentrations 1X, 2X and 5X measured field values in our model Shipyard Creek system. Dose-response experiments will test the potential for PCPs to bioaccumulate, cause endocrine action, and directly cause adverse effects on sensitive estuarine infaunal crustaceans (meiobenthic copepods). Meiobenthic copepods are keystone species in food-webs and the trophic transfer of lipophilic contaminants from sediments to fish, shrimps and crabs.
Summary/Accomplishments (Outputs/Outcomes):
Extensive multi-generational microplate culturing (copepod hatching stage through two broods) experiments were completed with the POPs lindane, DDD and fipronil sulfide. Identical tandem microplate experiments were run concurrently to yield sufficient copepod biomass for lipid-normalized body-burden measurements of these chemicals in copepods relative to aqueous exposure concentrations over 35-40 day periods. Multiple sublethal (i.e., < 20% mortalities, not significantly different from controls) POP concentrations were used so that individual’s developmental and reproductive endpoints could be measured with high statistical confidence over individual lifetimes. Lipid-normalized copepod body burdens were calculated to provide a basis for CBR’s of any POPs causing significant developmental or reproductive toxicity. Life-stage to life-stage transition probabilities, fecundities and mortalities were used to construct empirically-based Leslie-matrix population growth models for Amphiascus for each POP causing significant sublethal toxicity. Results were as follows:Expected Results:
The proposed work will, for the first time:
- address the potential for PCPs to bioaccumulate in trophically and ecologically important meiobenthic copepods;
- relate critical body residues of PCPs in field and lab populations to full lifecycle toxicity test endpoints of highest value to risk assessment (i.e., reproduction, population growth, population maintenance);
- and comprehensively evaluate endocrine disrupting potential of PCPs in crustaceans with regard to two hormonal systems intimately linked to growth and reproduction (i.e., ecdysone (molting) and vitellogenesis).
As copepod life-cycle testing is now before the OECD for adoption as a new endocrine disruptor screening tool, the information from this project will be of high value to OECD and environmental managers/agencies worldwide. Further, this work will generate new scientific knowledge related to the behavior of PCPs at the biochemical to whole organism to population levels.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
Other project views: | All 5 publications | 1 publications in selected types | All 1 journal articles |
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Type | Citation | ||
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Ferguson PL, Chandler GT, Templeton RC, DeMarco A, Scrivens WA, Englehart BA. Influence of sediment-amendment with single-walled carbon nanotubes and diesel soot on bioaccumulation of hydrophobic organic contaminants by benthic invertebrates. Environmental Science & Technology 2008;42(10):3879-3885. |
GR832211 (Final) |
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Supplemental Keywords:
chlorinated organics, water pollution, population modeling, invertebrate, sediments, endocrine disruption, risk assessment, meiofauna, benthos, RFA, Scientific Discipline, Health, Ecosystem Protection/Environmental Exposure & Risk, Toxicology, Environmental Chemistry, Ecosystem/Assessment/Indicators, Health Risk Assessment, Endocrine Disruptors - Environmental Exposure & Risk, endocrine disruptors, Ecological Effects - Environmental Exposure & Risk, Risk Assessments, Biology, Endocrine Disruptors - Human Health, bioindicator, ecological effects, ecological exposure, risk assessment, biomarkers, food web, assays, endocrine disrupting chemicals, sediment, sexual development, endocrine disrupting chemical, Leslie matrix population growth model, EDCs, exposure, animal models, toxicity, ecological impacts, amphipods, benthic copepods, estrogen response, hormone production, ecological risk assessment model, estuarine crustaceans, bioaccumulation, lifecycle toxicityProgress 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.