A chemical equilibrium model was used to predict the solution speciation of dissolved mercury (Hg) in the stratified water column of Offatts Bayou, a subestuary in Galveston Bay, Texas, which undergoes seasonal anoxia in bottom waters. Chemical equilibrium modeling was conducted using conditional stability constants and concentrations of Hg‐complexing organic ligands experimentally determined by competitive ligand equilibratio...

Five field trips were conducted in the San Francisco Bay‐Delta between May 2000 and October 2001 to investigate the sediment‐water exchange of total mercury (Hg) and monomethyl mercury (MMHg). Solid‐phase Hg averaged ~1 nmol g −1 and did not show any variability with depth or time or among sites. In contrast, solid‐phase MMHg showed considerable vertical, temporal, and spatial variability (0.4–66 pmol g −1 ), with the highest...

Surface water samples were collected from the San Francisco Bay estuary in September‐October 2000 (low flow) and March 2001 (high flow). Total mercury (Hg) concentrations were measured in unfiltered, filter‐passing ( n = 29) in unfiltered water. Suspended particulate matter (SPM) explained most particulate Hg concentrations in the northern reach. A significant portion of filter‐passing Hg was associated with colloidal Hg, acco...

The phase speciation and estuarine behavior of monomethyl mercury (MeHg) were determined in surface waters of the San Francisco Bay estuary in September‐October 2000 (low flow) and March 2001 (high flow). Colloidally associated MeHg was isolated using a cross‐flow ultrafiltration technique with a nominal molecular weight cutoff of 1 kDa. Filter‐passing MeHg was 57 ± 18% of the MeHg in unfiltered water in the fall and 39 ± 12%...