Cigarette butts in beach litter: Snapshot of a summer holiday.

Cigarette butts are considered the most common form of personal litter around the world. It is estimated that 5.5 trillion cigarettes are consumed globally each year and that 4.95 trillion are discarded in some natural or anthropic environment around the world. This study evaluated the pollution of urban beaches in the Brazilian Northeast by cigarette butts in relation to other types of litter. Samplings were conducted in a month of high season (January 2016), at eight heavily used beaches. In the place with the highest concentration of users in each beach, a 200 m transect (3 m width) was established parallel to the water on the most recent strandline. All items >1 cm were counted and classified into categories according to composition (plastic, cigarette butts, wood, glass, metal, paper and organic, such as food leftovers and coconuts) using a standard worksheet. Cigarette butts were considered as an isolated category of litter. A total of 10,880 items was registered. The most abundant items were plastics (44.96%) and cigarette butts (38.36%). Among plastics, the most abundant items were straws, metallic food packaging, sticks (lollipop and popsicle) and cups. Plastic fragments were also abundant in all beaches evaluated, corresponding to 14.5% of the total plastics.

Microplastics ingestion by a common tropical freshwater fishing resource.

Microplastics pollution is widespread in marine ecosystems and a major threat to biodiversity. Nevertheless, our knowledge of the impacts of microplastics in freshwater environments and biota is still very limited. The interaction of microplastics with freshwater organisms and the risks associated with the human consumption of organisms that ingested microplastics remain major knowledge gaps. In this study, we assessed the ingestion of microplastics by Hoplosternum littorale, a common freshwater fish heavily consumed by humans in semi-arid regions of South America. We assessed the abundance and diversity of both plastic debris and other food items found in the gut of fishes caught by local fishermen. We observed that 83% of the fish had plastic debris inside the gut, the highest frequency reported for a fish species so far. Most of the plastic debris (88.6%) recovered from the guts of fish were microplastics (<5 mm), fibres being the most frequent type (46.6%). We observed that fish consumed more microplastics at the urbanized sections of the river, and that the ingestion of microplastics was negatively correlated with the diversity of other food items in the gut of individual fish. Nevertheless, microplastics ingestion appears to have a limited impact on H. littorale, and the consequences of human consumption of this fish were not assessed. Our results suggest freshwater biota are vulnerable to microplastics pollution and that urbanization is a major factor contributing to the pollution of freshwater environments with microplastics. We suggest the gut content of fish could be used as a tool for the qualitative assessment of microplastics pollution in freshwater ecosystems. Further research is needed to determine the processes responsible for the high incidence of microplastics ingestion by H. littorale, and to evaluate the risk posed to humans by the consumption of freshwater fish that ingested microplastics.