Water, suspended particulate matter (SPM), and biota samples were collected from the
Taehwa River Estuary to determine the distributions, partitioning, and bioaccumulation
of arsenicals. Six forms of As were quantitated by the use of HPLC-ICP/MS. As was
found mainly near urban and industrial areas, and inorganic As(V) was the predominant
As form in both water and SPM. Particulate arsenicals were found at the greatest concentrations
in coarse particles (>180μm), followed by medium (30-180μm) and fine (0.45-30μm) particles,
in freshwater. Arsenical concentrations were similar across the three particle fractions
in saltwater. Field-based distribution coefficient (Kd) values for As depended strongly
on SPM, with a less robust dependence on salinity. Concentrations of As were greater
in macroalgae than in marine animals, such as fishes, bivalves, crabs, shrimps, and
gastropods. Overall, the results of the present study provide useful information on
the behaviors and fate of arsenicals in an estuarine environment.