Litter sources on the Polish Baltic shore – effect of increased anthropogenic pollution

The article summarises results of studies on litter concentrations on the Polish sea shore. Origin, mechanism of transport and source of litter are discussed. The main part of the data has been based on litter quality and quantity investigation in post-storm marine sediments. Data were collected in surface sediments since 2001 and in fossil washover fans dated 1988–2000 in different locations on the coast. Litter has been divided according to the material, use, size and origin. Analysis of litter quantity on beaches after storm surges showed an annual increase. The heavier surge, the more debris and mixed litter appear on the coast. A large increase in the amount of litter has been observed after the storm in 2009. The average amount of litter per 1 m2 has increased from 1.5 in 2001 to 17.5 in 2020. Among litter there is still a similar share of fishery and ship waste. The biggest growth was observed in waste of consumable origin. Plastic litter, including anthropogenic waste left on beaches, has increased to 80% in recent years. Most waste occurred on the coast adjacent to the Vistula River mouth.