Do toxicity identification and evaluation laboratory-based methods reflect causes of field impairment?

Area of Science:

• Environmental Toxicology
• Marine Biology
• Chemical Oceanography

Background:

• Sediment Toxicity Identification and Evaluation (TIE) methods are laboratory tools to identify sediment toxicants.
• A key limitation is verifying if lab-identified toxicants cause actual field effects.

Purpose of the Study:

• To determine if laboratory TIE methods accurately reflect field-observed ecological impacts.
• To validate the findings of TIE conducted on Elizabeth River sediments.

Main Methods:

• Conducted TIE on Elizabeth River sediments to identify toxicants.
• Collected field data including sediment and bivalve tissue chemical analyses.
• Utilized comet assay on in situ caged bivalves (Merceneria merceneria).
• Exposed organisms to sediment extracts and UV radiation for diagnostic response.

Main Results:

• TIE identified polycyclic aromatic hydrocarbons (PAHs) as the primary toxicants.
• Elevated PAH concentrations were found in sediments and bivalve tissues.
• In situ bivalves showed stress indicative of PAH exposure.
• UV radiation exposure induced a unique toxic response linked to PAHs.

Conclusions:

• Laboratory TIE findings for PAHs are consistent with field observations.
• PAHs are confirmed as the likely cause of ecological impairment in the Elizabeth River.
• Laboratory TIE methods effectively predict and explain real-world sediment toxicity.