Research Needs - trdoer20027

choose to forgo expensive biological testing and seek other disposal

options. The USACE databases, such as the Environmental Residue-

Effects Database (ERED), the Biota-sediment Accumulation Factor

(BSAF) Database, and the Environmental Effects of Dredging Database

(E2D2) are very useful compilations of information on dredged material

(all these databases are accessible at http://www.wes.army.mil/el/dots).

However, in some categories, a small fraction of the total data collected for

dredging projects is entered into the database. For example, the number of

BSAF entered into the database is a relatively small fraction of all of the

data that have been collected in the dredging program.

b. Field validation of existing or proposed biological tests. The

participants suggested that results of past field validation programs should

be examined to determine whether adverse effects are occurring at disposal

sites and whether biological tests are predictive of impacts at the site. In

addition, the USACE and USEPA should consider new field validation

programs at existing sites, e.g., the Historic Area Remediation Site

(HARS) in New York/New Jersey, associated with the DAMOS in New

England, or others.

c. Interpretation of chronic, sublethal bioassays. Participants noted that

there is a need for developing guidance for interpreting the results of

chronic, sublethal bioassays. For example, how should regulators make

decisions based on significant reductions in growth of benthic invertebrates

exposed to dredged material?

d. Interpretation of ecological significance of bioaccumulation.

Participants of the workshop were given a demonstration of the Corps'

ERED. This INTERNET-accessible database compiles and makes

accessible information on tissue concentrations of contaminants that are

associated with adverse biological effects, or in some cases, with no

adverse effects. Participants of the Effects Workgroup found this to be a

very useful tool for interpreting the significance of measured body burdens

of particular contaminants. Participants noted that other groups, including

USEPA, are also working on residue-effects databases. These groups

should combine efforts. The workgroup expressed some concern about the

level of knowledge that might be required to use information from the

database appropriately. For example, effects in one phylogenetic group

(e.g., molluscs) should not be used to estimate effects in a very different

group (e.g., fish). The group concluded that a numeric threshold or

criterion should not be established for any individual contaminant in the

database.

e. Predicting effects caused by mixtures of contaminants. Contaminants

that exert toxic effects by similar modes of action could produce effects

that are synergistic or antagonistic. Assessments that examine the effect of

each compound individually could underestimate or overestimate risk.

Chapter 3 Effects Assessment Workgroup Summary