MANY members of the Amazon’s Yanomami tribe have been poisoned with mercury, according to a report by Brazil’s top public health institute.
The study, published on Thursday, was conducted in nine villages along the Mucajai River, a remote region where illegal mining is widespread. Mercury is commonly used in illegal mining to process gold despite it being toxic.
The researchers collected hair samples from nearly 300 Yanomami of all ages. They were then examined by doctors, neurologists, psychologists and nurses.
The vast majority, 84 per cent, had contamination equal to or above two micrograms per gram, a level of exposure that can lead to several health problems, according to standards used by the United States Environmental Protection Agency and World Health Organisation (WHO).
Some 10 per cent of those tested surpassed the six-micrograms-per-gram threshold, a level of mercury poisoning often associated with more severe medical conditions.
Research teams also tested fish in the area and found high mercury levels in them. Eating such fish is the most common path of exposure.
Health effects can include decreased sensitivity in the legs, feet and hands, overall weakness, dizziness and ringing in the ears. In some cases, damage to the central nervous system can lead to mobility issues.
Paulo Basta, an epidemiologist with the Oswaldo Cruz Foundation, which led the testing, said: “Chronic exposure to mercury settles in slowly and progressively.
“There’s a wide spectrum of clinical actions that range from mild to severe symptoms.”
The WHO ranks small-scale gold mining as the single largest source of human-led poisoning.
Tribal leader Dario Kopenawa said: “Mining is the biggest threat we face in Yanomami land today.
“It’s mandatory and urgent to expel these intruders. If mining continues, so will contamination, devastation, malaria and malnutrition. This research provides concrete evidence of it.”
Brazilian President Luiz Inacio Lula da Silva has pledged to expel gold prospectors from Yanomami territory and improve health conditions there.
