Development of marine toxicity data for ordnance compounds

Area of Science:

• Environmental Toxicology
• Marine Biology
• Chemical Ecology

Background:

• Ordnance compounds pose environmental risks.
• Marine ecosystems are vulnerable to chemical contaminants.
• Comprehensive toxicity data is needed for risk assessment.

Purpose of the Study:

• To establish a marine toxicity database for eight ordnance compounds.
• To assess the toxicity of these compounds across five marine species.
• To identify the most sensitive toxicity endpoints and the most toxic compounds.

Main Methods:

• Conducted marine toxicity tests using sea urchins, macroalgae, polychaetes, redfish, and opossum shrimp.
• Evaluated endpoints including fertilization, embryological development, zoospore germination, survival, and reproduction.
• Analyzed eight specific ordnance compounds: dinitrotoluenes, trinitrotoluene, dinitrobenzene, trinitrobenzene, tetryl, picric acid, and RDX.

Main Results:

• Tetryl and 1,3,5-trinitrobenzene were identified as the most toxic ordnance compounds.
• Macroalga zoospore germination and polychaete reproduction were the most sensitive toxicity endpoints.
• Higher nitrogenation levels in dinitro- and trinitrotoluenes/benzenes correlated with increased toxicity.
• Picric acid and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) exhibited the lowest toxicity.
• The most toxic compounds (tetryl, 1,3,5-trinitrobenzene) were also the most degradable.

Conclusions:

• Ordnance compound toxicity varies significantly among marine species and chemical structures.
• Tetryl and 1,3,5-trinitrobenzene represent high-priority contaminants due to their toxicity and degradability.
• Zoospore germination and polychaete reproduction are key indicators for assessing ordnance compound ecotoxicity in marine environments.