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Over a period of eight months, a total of 26 atmospheric particulate matter samples were collected at the location of Tahiti and in other areas of French Polynesia, using a specially equipped sailboat. A 6-stage cascade impact or was used to separate aerosols in the following size classes: > 4,2-4, 1-2,0.5-1,0.25-0.5 and < 0.25 µm equivalent aerodynamic diameter. The resulting set of 156 size segregated aerosol samples was analyzed by particle-induced X-ray emission for 16 elements. This study deals with the concentrations of Na, Mg, Al, Si, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Sr and Pb. Enrichment factor calculations reveal that Na, Mg, S, A, K, Ca and Sr were little fractionated with respect to bulk sea water, whereas Al, Si, Ti, Mn and Fe presented no enrichment relative to the earth's crust. The anomalously enriched elements were Cu, Zn, Br and Pb. The multivariate technique factor analysis was used to identify the various aerosol sources. Dry and wet deposition modeling enabled us to estimate the atmospheric dry and wet transfer to the sea. Dry deposition velocities ranged from 0.04 to 0.2 cm S-1, while the scavenging rates were of the order of 2-3 x10-6 S-1. The resulting deposition rates are within the range given in the literature, with a good agreement for the deposition of Mn, Cu and Zn. It was found that dry deposition dominates over wet deposition for the sea derived elements, while for the crustal elements, the situation was the opposite. The estimated annual atmospheric deposition of Cu is equal to that of other geochemical cycles such as marine sedimentation and vertical mixing, whereas the deposition rates of mineral aerosol and Pb are much higher than those reported previously, indicating direct influence of local emissions from Tahiti.

The atmospheric input of up to 16 trace and other elements into the North Sea is further assessed from aerosol concentrations measured at a coastal station in Belgium, on ships during two cruises, and on a platform, in the years 1992-1994. The Slinn and Slinn model is used to calculate the dry deposition from the measured aerosol concentrations. The total (dry and wet) deposition into the North Sea environment is estimated to be (in tonnes per year): 560 for V, 1300 for Cr, 650 for Ni, 690 for Cu, 3500 for Zn and 1970 for Pb. The 'giant' particles dominate the fluxes. The atmospheric contribution to the total input into the North Sea, including riverine inputs and direct discharges, are estimated to be 28% for Cu, 29% for Zn and 57% for Pb. The inputs estimated from the experimental data are compared with results from a model applied for the same area and period. The experimental and the model results agree within 56%, which is considered as 'satisfactory' in view of both the experimental and the model uncertainties.