Europe's Largest Salt Lake Became A Reservoir Of Toxic Metals After A Century Of Salt Extraction And Poses Serious Threats

Europe’s Largest Salt Lake Became A Reservoir Of Toxic Metals After A Century Of Salt Extraction And Poses Serious Threats

Written by Romário Pereira de Carvalho

Published on 16/10/2025 at 18:38

Updated on 16/10/2025 at 18:39

Imagem: Ilustração artística feita por IA

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Waste From Old Salt Mines in Spain Continues to Contaminate the Mar Menor, the Largest Saline Lagoon in Europe. Even After Mining Ended in the 1990s, Toxic Metals Like Lead, Arsenic, and Mercury Still Threaten the Local Ecosystem

An old mining industry that operated between the late 19th century and the 20th century, around the Cartagena-La Unión mountain range in Spain, left a concerning legacy. The exploitation of the region’s salt reserves contaminated the Mar Menor, the largest saltwater lagoon in Europe, located in Murcia. The site has turned into a reservoir of toxic metals.

A recent study published in the journal Marine Pollution Bulletin investigated the excess heavy metals accumulated in the lagoon.

Although the industry ceased operations in the 1990s, rains continued to transport mine waste, keeping the contamination active.

ARTICLE CONTINUES BELOW

High Concentrations of Metals

Currently, the Mar Menor exhibits elevated levels of lead, arsenic, zinc, mercury, copper, and silver, exceeding recommended limits.

The highest concentrations are found in the southern part of the lagoon, the area closest to the old mining channels.

Historical data shows that the highest pollution levels occurred around the mid-20th century.

Despite the prohibition of mining discharges into water bodies since 1955, urban sources and boat paints continued to release metals into the lagoon, worsening the environmental issue.

Environmental Impacts and Risks

Today, the concentration of metals in sediments is lower than in the past, but the accumulation still reaches tons.

These elements remain deposited at the bottom of the lagoon, potentially representing a future threat.

According to researcher Irene Alorda from the Autonomous University of Barcelona (ICTA-UAB), the current impact does not directly affect living organisms, but it may increase over time.

This is because the combination of human pressures and environmental changes tends to worsen the situation.

Growing Threat

The study warns that climate change, eutrophication, and sediment suspension may again release metals into the ecosystem.

This reactivation would put marine life at risk and amplify the effects of contamination.

The research concludes that historical pollutants, combined with current environmental transformations, could intensify the degradation of the lagoon.

Therefore, the authors advocate for new conservation and monitoring strategies to protect the Mar Menor and prevent irreversible damage to the European ecosystem.

With information from Revista Galileu.

Europe’s Largest Salt Lake Became A Reservoir Of Toxic Metals After A Century Of Salt Extraction And Poses Serious Threats

Waste From Old Salt Mines in Spain Continues to Contaminate the Mar Menor, the Largest Saline Lagoon in Europe. Even After Mining Ended in the 1990s, Toxic Metals Like Lead, Arsenic, and Mercury Still Threaten the Local Ecosystem

High Concentrations of Metals

Environmental Impacts and Risks

Growing Threat

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Waste From Old Salt Mines in Spain Continues to Contaminate the Mar Menor, the Largest Saline Lagoon in Europe. Even After Mining Ended in the 1990s, Toxic Metals Like Lead, Arsenic, and Mercury Still Threaten the Local Ecosystem

High Concentrations of Metals

Environmental Impacts and Risks

Growing Threat

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