Development of marine toxicity data for ordnance compounds

A toxicity database for ordnance compounds was generated using eight compou nds of concern and marine toxicity tests with five species from different p hyla. Toxicity tests and endpoints included fertilization success and embry ological development with the sea urchin Arbacia punctulata; zoospore germi nation, germling length, and cell number with the green macroalga Ulva fasc iata; survival and reproductive success of the polychaete Dinophilus gyroci liatus; larvae hatching and survival with the redfish Sciaenops ocellatus; and survival of juveniles of the opossum shrimp Americamysis bahia (formerl y Mysidopsis bahia). The studied ordnance compounds were 2,4- and 2,6-dinit rotoluene, 2,4,6-trinitrotoluene, 1,3-dinitrobenzene, 1,3,5-trinitrobenzene , 2,4,6-trinitrophenyl-methylnitramine (tetryl), 2,4,6-trinitrophenol (picr ic acid), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The most sensi tive toxicity test endpoints overall were the macroalga zoospore germinatio n and the polychaete reproduction tests. The most toxic ordnance compounds overall were tetryl and 1,3,5-trinitrobenzene. These were also the most deg radable compounds, often being reduced to very low or below-detection level s at the end of the test exposure. Among the dinitro- and trinitrotoluenes and benzenes, toxicity tended to increase with the level of nitrogenation. Picric acid and RDX were the least toxic chemicals tested overall.