Risk Characterization Workgroup

d. How should effects of endocrine disruptors be considered or tested?

e. Does the occurrence of toxicity as defined under the Ocean and Inland

Testing Manuals (USACE/USEPA 1991, 1998)1 always equate to

unacceptable risk?

What are the important data gaps in ecological toxicity data? Are there

species that are particularly important at dredged disposal sites for which

no information is available?

g. What criteria should be used to select receptors (human and eco) at

greatest risk at various dredged material disposal sites? How can risks to

these receptors be minimized through appropriate site selection?

h. What are the most important sources of uncertainty in effects assessment?

How can these uncertainties be reduced? How can these uncertainties be

characterized?

Is there evidence for adverse effects on human and ecological receptors as

a result of dredged material disposal?

Should risk assessors account for the speciation of metals in environmental

samples (e.g., chromium or arsenic)?

k. What are the appropriate temporal and spatial scales for characterizing

effects?

What are the important areas for future research in effects assessment?

Risk Characterization Workgroup

a. Should Hazard Quotients be modified to express risk? What alternatives

are available?

b. When should weight-of-evidence approach be used in risk

characterizations? What approaches are useful?

c. What is the appropriate role of uncertainty analysis in assessing risk

(human or ecological) associated with dredged material management?

What tools are available to characterize uncertainty and when is it most

appropriate to use these various tools?

Reference information follows main text.

Appendix C Discussion Items