Physical properties of epilithic river biofilm as a new lead to perform pollution bioassessments in overseas territories

Abstract Chlordecone (CLD) levels measured in the rivers of the French West Indies were among the highest values detected worldwide in freshwater ecosystems, and its contamination is recognised as a severe health, environmental, agricultural, economic, and social issue. In these tropical volcanic is...

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Bibliographic Details
Main Authors: Dominique Monti, Cedric Hubas, Xavier Lourenço, Farid Begarin, Alexandre Haouisée, Laurence Romana, Estelle Lefrançois, Alexandra Jestin, Hélène Budzinski, Nathalie Tapie, Théo Risser, Jean-Louis Mansot, Philippe Keith, Olivier Gros, Pascal-Jean Lopez, Béatrice Lauga
Format: Article
Language:English
Published: Nature Publishing Group 2020-10-01
Series:Scientific Reports
Online Access:https://doi.org/10.1038/s41598-020-73948-7
Description
Summary:Abstract Chlordecone (CLD) levels measured in the rivers of the French West Indies were among the highest values detected worldwide in freshwater ecosystems, and its contamination is recognised as a severe health, environmental, agricultural, economic, and social issue. In these tropical volcanic islands, rivers show strong originalities as simplified food webs, or numerous amphidromous migrating species, making the bioindication of contaminations a difficult issue. The objective of this study was to search for biological responses to CLD pollution in a spatially fixed and long-lasting component of the rivers in the West Indies: the epilithic biofilm. Physical properties were investigated through complementary analyses: friction, viscosity as well as surface adhesion were analyzed and coupled with measures of biofilm carbon content and exopolymeric substance (EPS) production. Our results have pointed out a mesoscale chemical and physical reactivity of the biofilm that can be correlated with CLD contamination. We were able to demonstrate that epilithic biofilm physical properties can effectively be used to infer freshwater environmental quality of French Antilles rivers. The friction coefficient is reactive to contamination and well correlated to carbon content and EPS production. Monitoring biofilm physical properties could offer many advantages to potential users in terms of effectiveness and ease of use, rather than more complex or time-consuming analyses.
ISSN:2045-2322