• plastic leaching
• Lepidium sativum L.
• Glaucium flavum Crantz

High accumulation of plastic materials in the environment, especially in the marine coastal one, as well as their persistence and their negative effects on marine organisms, forced many governments to undertake strategies for plastic waste reduction, such as the development of biodegradable and compostable materials.
Plastic can reach sandy shores, considered sinks for the accumulation of plastic debris, both from terrestrial and marine environment, transported by winds and currents. Afterwards it can deposit in
dune environment, which is an ecologically and socio-economically important habitat but threatened by anthropic disturbances and climate change.
Carrier bags made of conventional plastic are among the most frequently found plastic items on sandy beaches, and recently also biodegradable/compostable carrier bags were found. Once in natural environment, bags are subjected to weathering (sunlight, high temperatures, winds, rainfall etc.), which promotes their initial degradation and fragmentation. Plastic bags can also adsorb pollutants during their permanence in the environment and release them afterwards.
Although the amount and distribution of plastic bags on beaches have been investigated by several studies, their degradation in dune environment and particularly their effects on dune vegetation and coastal habitats are still unknown.
Hence, the purpose of this study is to evaluate i) the possible alterations of the main chemicalphysical properties of the water medium in the presence of two different types of plastic bags (conventional and biodegradable/compostable), and ii) the possible effects of leaching from the plastic bags on sexual recruitment of plant species.
Leachates were obtained from each type of material, conventional and biodegradable/ compostable bags, and laboratory experiments were performed to evaluate the effects of leaching on seed germination and early plant development. Two plant species were selected: Lepidium sativum L., as it is a very sensitive species, frequently used as a model species in phytotoxicity tests, and Glaucium flavum Crantz, a common plant species along Mediterranean dune systems.
Results indicate that both the types of plastic bags can potentially influence early phases of plant development.