Bacterial Colonization of Microplastics at the Beaches of an Oceanic Island, Tenerife, Canary Islands

Abstract

(1) Isolated systems, such as oceanic islands, are increasingly experiencing important problems related to microplastic debris on their beaches. The formation of microbial biofilm on the surface of microplastics present in marine environments provides potential facilities for microorganisms to survive under the biofilm. Moreover, microplastics act as a vehicle for the dispersion of pathogenic organisms, constituting a new route of exposure for humans. (2) In this study, the microbial content (FIO and Vibrio spp. and Staphylococcus aureus) of microplastics (fragments and pellets) collected from seven beaches of the oceanic island of Tenerife, in the Canary Islands (Spain), was determined. (3) Results showed that Escherichia coli was present in 57.1% of the fragments and 28.5% of the pellets studied. In the case of intestinal Enterococci, 85.7% of the fragments and 57.1% of the pellets tested positive for this parameter. Finally, 100% of the fragments and 42.8% of the pellets analyzed from the different beaches contained Vibrio spp. (4) This study shows that microplastics act as reservoirs of microorganisms that can increase the presence of bacteria indicating faecal and pathogenic contamination in bathing areas.

Exploring plastic biofilm formation and Escherichia coli colonisation in marine environments

“…A recent study has detected both indicators on plastics collected from coastal waters with human impact, detecting higher densities of E. coli per item compared to the surrounding water (Liang et al, 2023 ). Moreover, these faecal indicators have demonstrated the capacity to adhere to plastic biofilms (Metcalf et al, 2023 ) and they have also been detected on plastic debris found on beaches (Hernández‐Sánchez et al, 2023 ; Rodrigues et al, 2019 ). The presence of E. coli attached to plastics raises concerns about the potential presence of faecal pathogens.…”