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Marine sediments from coastal Florida, USA impacted by Karenia brevis blooms were resuspended in seawater and irradiated in a solar simulator to determine if sedimentary bound PbTx-2 is photolytically released into the aqueous phase. All bulk and size-fractionated (

Discharge of dissolved organic matter (DOM) provides an important source of strong Cu-complexing ligands to the coastal ocean waters of Long Bay off the southeast coast of North Carolina. Concentrations of strong Cu ligands (∑L i at fixed K CuL ′=10 13.5 ), measured using competitive ligand equilibration-cathodic stripping voltammetry with 8-hydroxyquinoline (8-HQ) as the competing ligand, were linearly correlated with dissolved organic carbon (DOC) concentrations (∑L i =0.23DOC−14, r 2 =0.81, p ≪0.01, n =9) in Long Bay transect samples. The relationship between ∑L i and DOC measured in this study was very similar to that measured in a previous study for Cape Fear estuarine sites. The Cape Fear provides 1.8×10 6 mol of strong Cu ligands annually to Long Bay with a ratio of ligand/DOC of 1.7×10 −5 mol g −1 C. For South Atlantic Bight (SAB) shelf waters, yearly discharge from organic-rich rivers may provide up to 1.7×10 7 mol of strong Cu ligands. A river flux of this magnitude could support 1.6 nM strong Cu-complexation capacity throughout the SAB water column, or up to 50% of the total pool of strong Cu-complexing ligands. Estimates for the worldwide river discharge of terrestrial DOM indicate this source could support 0.03–0.2 nM strong Cu complexation capacity, or a maximum of 20% of the global ocean reservoir of strong Cu ligands.