PARTICULATE TRACE-METALS ABOVE THE SOUTHERN BIGHT OF THE NORTH-SEA .2. ORIGIN AND BEHAVIOR OF THE TRACE-METALS

Ninety-six aerosol samples were collected in all seasons and wind conditions in the troposphere of the Southern Bight of the North Sea. About one third of these samples were collected with a six stage cascade impactor sampler. Considering that in each sample eight metals were analyzed, the data set we had to handle consisted of about 2000 results. In addition, wind directions and wind speeds are also included in this data set. To interpret all these results, we relied upon two methods: (1) enrichment factors were calculated and allowed us to identify some of the metal sources; (2) three factors resulted from a multivariate analysis method: in the first factor we only find Na, representing the marine component; the second factor includes Al (a crustal and anthropogenic component) coupled to Pb, Cu and Cd (anthropogenic components) and anticorrelated with the wind speed; the third factor couples Fe, Mn and Zn with the south component of the wind. When size fractionated samples are considered (six stages) differences between Fe, Mn, Zn and Pb become, however, apparent.