High Mercury Levels Detected in Amazon River, Raising Public Health Concerns

Researchers from Harvard University and Amazonas State University have reported alarming levels of mercury in the Madeira River, a vital tributary of the Amazon. This expedition found elevated concentrations of mercury in the water, which poses significant risks to residents who rely on the river for drinking water and fish consumption.

The study began over nine miles upstream from the municipality of Humaitá, where scientists collected and analyzed water, sediment, and fish samples. Although the mercury levels detected did not exceed Brazilian legal limits, they remain higher than global averages and raise concerns over pollution from illegal gold mining in the area. Biologist Adriano Nobre explained that the operation of illegal miners contributes heavily to mercury contamination, as they use the chemical in gold extraction processes.

Certain fish species consumed by locals exhibited mercury concentrations above safe limits, particularly carnivorous fish which accumulate pollutants in their bodies. This poses a risk not just to local communities but potentially to populations downstream in the Amazon Basin and the Atlantic Ocean.

Mercury is known for its adverse health effects, including damage to the brain, heart, and kidneys, especially in vulnerable populations such as pregnant women and young children.

The study also aims to establish a water quality index for the region and continue monitoring efforts through upcoming expeditions. Researchers are hopeful that their findings will spur conservation actions and greater awareness about the environmental and health risks associated with illegal mining activities.