Tin and methyltin species in seawater: concentrations and fluxes.

The concentrations of tin and methyltin species in rivers, an estuary, and the surface and deep ocean generally are less than 50 picomoles of tin per liter. Estuarine profiles and river concentrations suggest that the dissolved riverine input of tin is only a minor source of this element to the oceans. Oceanic concentrations of inorganic tin decrease both with distance from land and with increasing depth from the surface, an indication of atmospheric transport to the surface ocean. Most of the contemporaneous eolian influx of tin to the oceans is anthropogenic. The vertical structure oftin concentrations in the northwestern Atlantic can be explained in terms of a model based on eolian input, advective processes, and removal of tin by particulate scavenging.