In pictures: Welcome to the deadliest waters on planet Earth

Join the scientific mission to see what secrets of early life can be uncovered in the salt lakes of Chile’s Atacama Desert.

By James Cutmore

Published: Saturday, 28 January 2023 at 12:00 am

One of the driest places on the planet is not where you would expect to find some of the most dangerous waters on Earth. But high in the Andes mountains of Chile, the Salar de Atacama salt flats are home to some of the hardiest of bacteria, surviving in highly toxic lakes full of salt, lithium and arsenic.

Now scientists from the French National Centre for Scientific Research (CNRS) and the Chilean University of Antofagasta are taking part in the study of microorganisms, with the aim of learning more about how life survives in such conditions, and how those secrets may also help us to fight plastic pollution.

The team, led by microbiologists Purificación López-Garcìa and David Moriera of CNRS, has been examining 15 of the salt lakes, taking samples from the salty waters of the lagoons and the burning waters of the geysers. The team will then produce an inventory of the microbial life contained in salt crystals, hot basins, geysers and blood-red lakes.

However, the study also highlighted the damage being done to the salt flats due to the mining of lithium – an essential element in the production of rechargeable batteries.

“A lot of water is needed for lithium extraction so that many of these unique ecosystems are disappearing,” Professor López-Garcìa told BBC Science Focus. “The water is gone, with it the microbial ecosystems that we study and, beyond them, the rare but idiosyncratic fauna and flora in the altiplano.”

Scientists are hopeful that in the future, the power to degrade plastics by extremophile bacteria found in places such as these will help develop new and safe ways to tackle plastic pollution.

Laguna Roja

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An aerial view of the Laguna Roja in northern Chile. Even though the high concentration of salt gives the lake its red colour, this lake is nearly as hot as it looks. The water here can reach temperatures up to 50°C. Photo by Olivier Grunewald
©Olivier Grunewald

High in the Andes

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The Salar de Huasco has experienced a drop in its water levels in the past few years. Scientists believe this loss of water is either due to climate change, which reduces rainfall in this region, or the removal of water due to Lithium mining operations. The Salar de Atacama is home to the largest lithium mining programme in the world, essential in the production of rechargeable batteries. Photo by Olivier Grunewald

Laguna Pujsa

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At 4,700 meters above sea level, the colourful lake of Laguna Pujsa is full of mineral elements and microorganisms. Scientists from the CNRS and the Chilean University of Antofagasta collected water and took core samples of earth to look for extremophiles capable of living in this hyper-salty environment. The violent wind that rises every day in the early afternoon makes working conditions difficult for the teams. Photo by Olivier Grunewald

Laguna Brava

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Microbiologist David Moreira of CNRS takes a rock sample from the Laguna Brava salt lake on the high plains of the Salar de Atacama, Chile. This sample will be taken back to France to be catalogued and studied. Photo by Olivier Grunewald

Laguna Tara

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At an altitude of over 4,300 metres, Laguna Tara, near San Pedro de Atacama in Chile, is an area teeming with wildlife, including flamingoes and Andean foxes. Photo by Olivier Grunewald

Boating on Laguna Roja

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Scientists from the French National Centre for Scientific Research (CNRS) and the Chilean University of Antofagasta collect water samples from Laguna Roja in northern Chile. The team ventured onto this lake in a small inflatable boat, searching for microorganisms in the water that manage to survive in such inhospitable conditions. Photo by Olivier Grunewald

Salar de Llamara

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At a much lower altitude, at only 1,000 metres above sea level, the Salar de Llarama is at the heart of the driest zone of the Atacama. This lake is known for its salt formations and is one of the sites where the biomass is essentially made up of microorganisms. Photo by Olivier Grunewald

More images from Science Focus:

Collecting samples

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Every evening during the study, the scientific team from the CNRS and the Chilean University of Antofagasta sort through the collected samples from the lakes, filtering out water and carefully cataloguing samples of life they have collected. Photo by Olivier Grunewald

Taking the samples back to the lab

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In total, more than 120kg of samples were brought back to France to be cultured and analysed on the premises of the University of Paris Saclay, where the CNRS team is based. Once analysed, the studies will produce large amounts of DNA data, and the scientists expect to find new groups of microbes not previously discovered. Photo by Olivier Grunewald

Beautiful but inhospitable

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Steam rises off the hot waters of Laguna Roja, high in the Chilean Andes. Working here is dangerous for several reasons. Firstly, the high altitude means that there is a lack of oxygen, and requires a gradual acclimatisation process. UV radiation is also strong, therefore skin and eyes must be protected. Photo by Olivier Grunewald

 

About our expert

Purificación López-García is research director of the French National Centre for Scientific Research. Her work focuses on microbial lineages and the early evolution of life on Earth. 

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