This paper presents a statistical analysis of the oil spill detection in European coastal waters, as well as a methodological description on how to distinguish by means of multi-fractal analysis oil spills and biological tensioacive activity in the ocean surface. We discuss different satellite detected oil spills and their distribution in size. The detectability of the oil by SAR derives from the decrease in roughness of the ocean surface at small wavelengths and depends strongly on the wind speed as well as other varying environmental conditions. In particular, we concentrate on the use of scaling approaches to discriminate between antropogenyc oil spills and natural slicks, also named as look-alikes SAR detections.