Measurements of total, methyl and dissolved gaseous mercury in surface seawater microlayers of the Seto Inland Sea

Abstract

The total, methyl and dissolved gaseous mercury (Hg) in the marine surface microlayer, for which there have been few data, were investigated in the eastern Seto Inland Sea. The results showed that the concentrations of total and methyl Hg in the microlayer layer were higher than those in the surface seawater below, but in some cases the concentrations in the surface seawater at other sites were higher. On the other hand, dissolved gaseous Hg concentrations in the microlayer layer were found to be 2.6 to 29 times higher than in the surface seawater below and in other surface waters. Dissolved gaseous Hg is an important parameter for Hg exchange between atmosphere and sea surfaces. Thus, further investigation data should be necessary.