With plastic production reaching an astounding 400 million tons annually, a significant amount of mismanaged waste travels from inland areas to water systems, eventually ending up in riverine and coastal environments. In these aquatic habitats, plastics and boat biocide coatings undergo physical degradation, breaking down into microplastics (MPs; <5mm), and release associated chemicals into the water. Exposure to these leachates has been linked to adverse effects in aquatic organisms, such as increased mortality and delayed larval mortality. Additionally, these organisms face various other environmental stressors, including rising temperatures due to global climate change. This study aimed to assess the effects of leachates from plastic items and boat coatings on Nitokra spinipes, a key species in estuarine food webs, within the context of global change. Samples collected in Nieuwpoort, Belgium, indicated that polyethylene and polypropylene were the most abundant plastics in the area, with antifouling paint particles also present. Based on these findings, we selected polypropylene and a boat coating to produce leachates. To evaluate the toxicity of these leachates, we exposed N. spinipes nauplii to them until they reached the juvenile stage (7 days) and monitored their development and mortality rates. An LC50 test was also conducted on adults at 22°C and 25°C for 72 h. We hypothesize that exposure to both leachates will result in increased mortality of the nauplii and that copepods will exhibit higher sensitivity at elevated temperatures. Our results contribute to the risk assessment of plastic and coating-related litter in regional estuaries. |
