Loire Sentinelle expedition

1000 km expedition to defend the Loire River

From the source of the Loire to the estuary, a pair of biologists have drawn up the first map of the river’s biodiversity and its contamination by microplastics.

For three months, Barbara Réthoré and Julien Chapuis embarked on a scientific and sensitive exploration of France’s largest river, covering almost 1,000 kilometres. Called Loire Sentinelle, their project aims to learn from the Loire in order to protect it more effectively.

In scientific terms, the two biologists are collecting DNA traces “left by all living things in their environment” and microplastics “left behind by humans alone”.

For the two biologists, “the idea is to get an overall view of what is happening in the Loire so that we can understand the causes and measure the consequences of this pollution [linked to microplastics], which is invisible, widespread and still little studied”.


Quentin Hulo photo-journalist

Juliette Cottin journalist