Temperature as a component of Toxicity Identification Evaluation for Pyrethroid InsecticidesEPA Grant Number: F6D90524
Title: Temperature as a component of Toxicity Identification Evaluation for Pyrethroid Insecticides
Investigators: Harwood, Amanda
Institution: Southern Illinois University - Carbondale
EPA Project Officer: Zambrana, Jose
Project Period: September 1, 2006 through September 1, 2008
Project Amount: $67,184
RFA: GRO Fellowships for Graduate Environmental Study (2006) RFA Text | Recipients Lists
Research Category: Health Effects , Fellowship - Environmental Toxicology , Academic Fellowships , Hazardous Waste/Remediation
As interest in identifying contamination sources increases, various Toxicity Identification Evaluation (TIE) methods have been developed. Preliminary TIE methods have been proposed for several pesticide classes. A TIE for pyrethroid insecticides in sediment has not been completely developed. The main objectives of this study are to examine the effects of temperature on the acute toxicity of sediment associated insecticides to midge larvae (Chironomus tentans) and oligocheate worm (Lumbriculus variegates) at two temperatures (13 and 23°C). The toxicokinetic parameters (uptake, biotransformation, and elimination) for these species will then be used to mechanistically explain these changes in toxicity. Data will then be used to evaluate temperature as a component of TIE for pyrethroids.
Four compounds will be examined, two pyrethroids (permethrin and lambda-cyhalothrin), a carbamate (carbaryl), and an organophosphate (chlorpyrifos). These four classes represent the diversity that would be present in field sediments. Toxicity testing will be preformed in accordance with standard U.S. EPA methods at both temperatures for each organism to determine the effect of temperature on acute toxicity. Toxicokinetic experiments will approximate uptake (ku), biotransformation (km), and elimination (ke) coefficients. This data will also be used to calculate biota-sediment accumulations factors (BSAFs) and biological half-lives for these pesticides.
The standard approach for assessing which contaminants in an environmental matrix are problematic has been through TIE. This research examines temperature as a TIE component for pyrethroid insecticides in sediments, allowing for the identification of the individual insecticide classes as well as establishing a whole-sediment TIE method for insecticides. Development of such methods simplifies toxicity source identification, aiding in further pesticide regulation.