Multi-elemental composition and sources of the high Arctic atmospheric aerosol during summer and autumn

During the International Arctic Ocean Expedition 1991 (IAOE-91), total (i.e., 2 mu m EAD) size fraction. The highest levels of the anthropogenic metals and of the mineral dust elements were found in air which in general had not been in contact with large continental or anthropogenic source regions during the last 5 or even 10 days prior to its arrival, and in an area of the pack ice which was influenced by continental river run-of from the Siberian coast. It is tentatively suggested that the elevated concentrations of both those metals and the crustal elements were the result of local mechanical windblown generation of coarse aerosols from the river effluent materials which were present on or at the surface of the ice. By relating the observed atmospheric nss-S levels to 3-dimensional air back trajectories, and from intercomparing the nss-S time trend with the trends of various other particulate species, it was concluded that the nss-S was mainly from anthropogenic origin (transported through the free troposphere) near the end of the IAOE-91, but that the marine biogenic sulfur source must have dominated during the first month and a half of the expedition

Biogeochemical behaviour of Cd, Cu, Pb and Zn in the Scheldt estuary during the period 1981–1983.

Abstract Cu, Cd, Zn and Pb concentrations in both dissolved and particulate phase were assessed during 1995. Data Quality Assurance was an integral part of this study and involved all major steps of the analysis procedure such as sampling, sample handling, preconcentration and determination. Desorption and redox processes clearly control the dissolved Cu and Cd profiles. Mobilisation of dissolved Zn is small and essentially restricted to the low salinity area and the late spring survey. Dissolved Pb shows the clearest dilution pattern. The parameters representative of these processes (dissolved oxygen and salinity) also correlate very well with the particulate metal profiles. In addition, the plankton activity (expressed by the chlorophyll-a levels) may influence the dissolved and particulate metal profiles. In combination with desorption and redox processes, seasonal variations were induced