Deforestation Threatens Public Health. Securing Indigenous Land Rights Can Help, Researchers Find

Indigenous territories are a crucial bulwark against the destruction of the Amazon rainforest. A new peer-reviewed study shows they also safeguard the health of millions living there. 

The study, published Thursday in the journal Communications Earth and Environment, examined the impact Indigenous territories have on human health across the Amazon biome, a region that’s home to 33 million people.

Amazonian municipalities located close to Indigenous lands with intact forest have reduced risk from two categories of health harms, the study found: fire-related illnesses and diseases spread by animals and insects.

The best outcomes were near Indigenous communities with legally recognized land titles. 

The researchers, a team from across four countries and led by the International Union for Conservation of Nature and Natural Resources, used spatial, epidemiological and land-record data from 2000 to 2019 across eight Amazonian countries and French Guiana. Their study, they said, is the first to quantify the health benefits of Indigenous territories in the Amazon rainforest. 

Deforestation is the root cause of the illnesses the research focused on. Forest fires, for instance, release dangerous particulate matter into the air. The particles, known as PM2.5 because they measure a tiny 2.5 microns or less, can enter the bloodstream through the lungs, leading to heart disease, stroke, emphysema, lung cancer, bronchitis, other respiratory problems and increased risk of death.

In Brazil alone, preventing forest fires from 2008 to 2018 could have averted 16,800 premature deaths in South America, according to the study. 

Humans are the leading cause of fires in the Amazon. Ranchers and farmers intentionally set fires to clear forests for pasture. As more forest burns, greater amounts of carbon dioxide spew into the atmosphere, warming the Earth and sparking a negative feedback loop that creates drier and hotter temperatures, making wildfires more likely. Logging, mining and infrastructure development also cause deforestation and make what remains more vulnerable to fire. 

A growing body of research shows Indigenous-managed lands have lower levels of tree loss, especially when Indigenous communities have secured legal title to their lands. Healthy forests are less fire-prone and help remove PM2.5 from the environment by absorbing it back into the landscape. 

“Protecting more forest areas under Indigenous people management could significantly reduce atmospheric pollutants and improve human health outcomes,” the study said. 

The Amazon has lost an area the size of New Mexico to deforestation in the last 20 years, while fires have grown more extreme. 

This destruction also brings people and wildlife into closer proximity, making it easier for zoonotic and vector-borne diseases like malaria to spread. Monkeypox, Ebola and HIV all emerged from forests. 

“Indigenous Territories typically buffer against deforestation and thus help maintain biodiversity and overall ecological stability,” and those conditions minimize disease outbreaks, the report said.

More than 28 million cases of fire-related, zoonotic and vector-borne diseases were reported throughout the Amazon region between 2001 and 2019, the report said. While most were fire-related, vector-borne and zoonotic diseases accounted for about 20 percent of cases, malaria in particular. 

“This study offers new evidence that forests themselves are a balm for fire-related threats to people’s lungs and hearts, to illnesses like Chagas, malaria and spotted fevers,” Paula Prist, senior program coordinator of the forests and grasslands program of the IUCN and report co-author, said in a statement. 

Still, the researchers cautioned that while well-conserved Indigenous lands generally help lower the risk of disease, the relationship is not straightforward and outcomes depend on the surrounding landscape. 

The relationship between Indigenous territories, forest cover outside those territories and fragmentation on fire-related diseases “is nonlinear and complex,” the researchers said. Large, contiguous forested areas, they added, seem necessary to best protect human health. 

The links between Indigenous territories and outbreaks of zoonotic and vector-borne diseases are even more complex. The researchers said their findings show these territories can mitigate disease risk from forest fragmentation only if they cover more than 40 percent of the municipality. They called their study a “first step” and said that more research is needed to better understand the issue. 

Roughly 3,000 Indigenous territories crisscross the Amazon biome. Many lack legal security, leaving them more vulnerable to logging, mining and other drivers of forest loss. 

In Brazil, about a third are still without formal legal title despite a constitutional obligation requiring the government to provide it. In Peru, lawmakers last week voted against creating a protected area for uncontacted Indigenous peoples. In Suriname, the government has yet to legally recognize Indigenous lands. 

And across the region, transnational criminal organizations involved in illegal mining are pressing further into the Amazon, with major impacts on the forest and Indigenous communities. 

Prist said: “Ensuring Indigenous communities have strong rights over their lands is the best way to keep forests and their health benefits intact.”

Katie Surma

Reporter, Pittsburgh

Katie Surma is a reporter at Inside Climate News covering the rights of nature movement and international environmental justice. Her work has a strong focus on the intersection of human rights and the environment. Before joining ICN, she practiced law, specializing in commercial litigation. Her journalism work has been recognized by the Overseas Press Club, the Society of International Journalists, the Society of American Business Editors and Writers and others. Katie has a master’s degree in investigative journalism from Arizona State University’s Walter Cronkite School of Journalism, an LLM in international rule of law and security from ASU’s Sandra Day O’Connor College of Law, a J.D. from Duquesne University, and was a History of Art and Architecture major at the University of Pittsburgh. Katie lives in Pittsburgh, Pennsylvania.

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