ABSTRACT
Persistent contaminants in the environment affect human health and ecosystems. It is important
to assess the risks of these pollutants for environmental policy. Ecological risk assessment
(ERA) is a tool to estimate adverse effects on the environment from chemical or physical
stressors. It is anticipated that ERA will be the main tool used by the U.S. Department of Energy
(US DOE) to accomplish waste management [1]. Toxicity bioassays are the important line
of evidence in an ERA. Recent environmental legislation and increased awareness of the risk of
soil and water pollution have stimulated a demand for sensitive and rapid bioassays that use
indigenous and ecologically relevant organisms to detect the early stages of pollution and
monitor subsequent ecosystem change.