During a survey at six stations in the Dover Strait, from July 1990 to November 1991, water samples were collected to measure : suspended sediment load and its organic content; particle characteristics; photosynthesis pigments; and heavy metals. In this contribution, particle measurements are interpreted in terms of hydrodynamical effects and seasonal evolution. Multi-modal grain size spectra are indicative of depth and cross-sectional variations, from die coastline to the central waters. Tidal variations, biological productivity and wind effects can be identified. Suspended particulate matter (SPM) components (determined using SEM, when combined with size spectra) illustrate hydrodynamical, geomorphological and biological effects on the composition of the suspended matter. Living and non-living diatom valves, used as particulate tracers, provide information on the sources and hydrodynamic behaviour of the suspended particles. Although the Seine input is high, riverine SPM input is not detected within the Dover Strait. SPM fluxes from the Eastern Channel into the southern North Sea, across the Dover Strait, originate mainly from: Atlantic waters; coastal and sea bed erosion; biological activity; and resuspension from the intertidal zone. SPM studies in the Eastern Channel could provide information on the complex behaviour of river pollutants over the region.