Comparison of the disposition of several nitrogen-containing compounds in the sea urchin and other marine invertebrates.

1. The disposition of an aromatic amine and three aromatic nitro compounds was investigated in the sea urchin, Strongylocentrotus purpuratus. 2. The sea urchin rapidly eliminated injected compounds. The elimination rate constants decreased in the order p-toluidine greater than p-nitroanisole = p-nitrophenol greater than p-nitrotoluene. The fraction of total injected compound eliminated in 8 h was lowest for p-nitrophenol less than p-toluidine less than p-nitrotoluene less than p-nitroanisole. 3. Biotransformation for the sea urchin was primarily reduction of the nitro group followed by acetylation of the amine. 4. Other animals, starfish (Pisaster ochraceus), sea cucumber (Cucumaria miniata), gum boot chiton (Cryptochiton stelleri) and mussels (Mytilus californianus), injected with p-nitroanisole exhibited a trend toward oxidative biotransformation. 5. Elimination of parent compound was the major pathway for reducing body burden of xenobiotics for the invertebrates studied. 6. p-Toluidine oxidizes during analysis and was thus not suitable for studying biotransformation.