Mercury Poisoning Spreads through Amazon Communities Due to Contaminated Fish

The Madeira River in Brazil's Amazon is contaminated with high levels of mercury, posing serious health risks to local residents. A study by researchers at the Federal University of Rondônia found that mercury concentrations among residents of Lake Puruzinho community are among the highest recorded in the Madeira River Basin.

Researchers analyzed 42 scientific studies published between 1997 and 2024, which showed evidence of mercury exposure among residents of at least 249 Indigenous and riverside communities over that 27-year period. The study also found that another 702 communities are at risk because they're located near illegal mining hotspots.

Residents in Lake Puruzinho community have drastically reduced their consumption of fish like tucunaré, which was a staple of their diet for years, after learning about the mercury contamination. Maria Rogelina Soares da Silva dos Santos, a fisher and homemaker, said 'there was a lot of mercury in our hair [because] of the fish, the tucunaré, which we eat a lot.'

Ronaldo de Almeida, a co-author of several studies on the effects of mercury in the Madeira River, explained that 'fish is, unfortunately, the main route of entry for the ingestion of mercury.'