They're Going Door To Door In The Amazon To See Why People Get Sick

May 19, 2015
Originally published on May 19, 2015 10:14 am

Is it the mercury or the malaria?

Or maybe it's something else entirely that's making people sick in the Peruvian Amazon.

Those questions are bedeviling researchers from Duke University who have been studying gold mining in the region. Illegal mining has exploded in the area in the past decade, and the people living downriver have a variety of medical issues, from malaria to anemia to high blood pressure.

Researchers have documented that mercury used in illegal gold mining ends up hundreds of miles downstream from the mines, and it eventually ends up in fish — a major local source of protein.

But you can't see or smell mercury in fish.

So it's hard to measure the impact on residents. One of the main effects of mercury is that it causes developmental delays in children. Toxic exposure can cause severe fatigue, headaches and vomiting. Those symptoms could be the result of mercury. Or not. There's very little data on all the other things that could be responsible for health issues in the area.

To try to determine the possible health effects of the mercury, this year the researchers launched a massive survey that stretches from the Eastern slope of the Andes down into the plains of the Amazon basin.

The researchers are based in the sleepy little town of Salvacion, six hours east of Cusco when the roads are open. Mudslides often block the road during the rainy season, so Salvacion feels even more cut off than it already is.

At a simple, wood plank house in Salvacion, Dr. Ernesto Ortiz and two of his colleagues are about to start interviewing the family of Valentino Escobar Gutierrez. The entire health survey of Escobar's family will take two to four hours to complete.

"We're going to sample for malaria and for dengue," Ortiz says. "We are also testing for tuberculosis. Also testing for chronic diseases, diabetes, hypertension, kidney function, nutritional status, so we are going to have a big picture of how things are going."

Escobar, 45, wants to know why they need to take so much blood.

Ortiz explains with a laugh that each tube of blood will be used to test for a different disease or health condition. And he assures Escobar they're taking only a tiny portion of all the blood in his body.

"With one glass of water, you'll replace all of this," Ortiz assures him.

This study is all about gathering lots and lots of data. Ortiz and his colleagues at Duke plan to enroll 5,000 people. At each house they'll take medical histories. They'll ask about diet, income, education and past illnesses. They'll get blood, urine and hair samples to check a range of health conditions.

They're also testing for mercury exposure.

Ortiz says it's particularly important to understand how mercury from the gold mines could be affecting children.

"If [a child] is exposed to mercury for a long time, you get problems with brain development. They won't be able to have good attention, to learn things," Ortiz says. Sometimes they won't even be able to finish school. If that happens during early childhood, there's no return, they won't be able to heal from that damage."

So people have no idea whether they or their kids are consuming dangerous levels of the heavy metal. This study could flag that potential health threat.

Dr. Fernando Medieta, who's in charge of the local health district, is excited about the Duke survey for other reasons. He sees the study as a way to get data about his community that he would never have the time or the resources to collect on his own.

"This study is important because it's going to allow us to see the health of the whole population," he says. "And allow us to come up with ways to make things better.

This study is funded by Texas-based Hunt Oil Co., which is exploring for natural gas in the region. The researchers stress that their survey is an independent, academic project controlled by Duke.

Medieta runs a small hospital in Salvacion. He also oversees 15 small, bare-bones clinics scattered through the jungle. Ten of the posts are accessible only by river and the most distant one takes at least four days to reach by canoe.

For him mercury isn't his most pressing issue. In some of the villages he serves, half the children are malnourished. Water and mosquito-borne diseases are major problems. And chronic diseases like diabetes and hypertension are on the rise.

Down the road all the data collected by the Duke team might help show how climate change, new roads, new vaccination campaigns or environmental toxins like mercury affect disease rates in this part of the Amazon Basin.

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RENEE MONTAGNE, HOST:

And here's a dilemma facing researchers working in the Amazon. They have documented that mercury used in illegal gold mining there ends up hundreds of miles downstream from the mines. But it's hard to measure what impact that mercury is having on people there because there's so little data on all the other things that might cause sickness. So researchers from Duke University have launched a health survey that is massive. NPR's Jason Beaubien traveled to the Peruvian Amazon and sent this report.

JASON BEAUBIEN, BYLINE: Life is so slow in the town of Salvacion that dogs sleep in the middle of the main streets. In the early morning, before the sun crests the lush hills that surround the town, the air is still cool and refreshing.

UNIDENTIFIED MAN: (Speaking Spanish).

UNIDENTIFIED WOMAN: (Speaking Spanish).

BEAUBIEN: Ernesto Ortiz and two of his colleagues have just arrived at the simple wood plank home of Valentino Escobar Gutierrez. They're about to start a health survey of Escobar's family that will take anywhere from two to four hours to complete. As the researchers layout their scales, test tubes and syringes, Escobar eyes their equipment with suspicion.

VALENTINO ESCOBAR GUTIERREZ: (Speaking Spanish).

ERNESTO ORTIZ: (Speaking Spanish).

GUTIERREZ: (Speaking Spanish).

BEAUBIEN: The 45-year-old Escobar wants to know why they need to take so much blood.

ORTIZ: (Speaking Spanish).

BEAUBIEN: Ortiz explains that each tube of blood will be used for a different condition, and he assures Escobar that they're taking only a tiny portion of all the blood that's in his body.

ORTIZ: (Speaking Spanish). (Laughter).

BEAUBIEN: Ortiz and his colleagues at Duke plan to enroll 5,000 people in this study. At each house, they'll take exhaustive medical histories. They'll ask about diet, income, education and past illnesses. They'll get blood, urine and hair samples for a battery of tests.

ORTIZ: We're going to do a sample for malaria, for dengue. We're also testing for TB - tuberculosis. We're also testing for chronic diseases - diabetes, hypertension, kidney function, nutritional status. So we're going to have a big picture of how things are going.

BEAUBIEN: They're also testing for mercury. This team from Duke, in earlier studies, has documented the environmental spread of mercury hundreds of miles downriver from the illegal gold mines. But it's been hard to assess the full effect of the mercury because there's little data on what other things might be affecting people's health here. The goal of this current study is to help change that. The census stretches from the foothills of the Andes, where there's little mining, all the way down into the plains of the Amazon basin, where there's a lot. Mercury used to extract gold ends up in local fish, where, Ortiz says, it can cause major developmental delays in children.

ORTIZ: If that happens during early childhood, there's no return. They won't be able to heal from that damage.

BEAUBIEN: You can't see or smell mercury in fish, so people have no idea whether they're consuming dangerous levels of the heavy metal. This study could flag that potential health threat.

FERNANDO MEDIETA: (Speaking Spanish).

BEAUBIEN: Fernando Medieta, who's in charge of the local health district, is excited about the Duke survey for other reasons. On this day, at his base at the small government hospital in Salvacion, Medieta is yelling into a CB radio. He's trying to connect with one of his employees at a health post several hours downriver. Medieta oversees 15 of these posts. They're small, bare-bones clinics scattered through the jungle. Ten of the posts are only accessible by river, and the most distant takes at least four days to reach by canoe.

MEDIETA: (Through interpreter) The principal problem that we're trying to combat in these areas is malnutrition among children under the age of five. It's extremely high. More than half the children are chronically malnourished.

BEAUBIEN: And there are numerous other health issues in the area. Water and mosquito-borne diseases are major problems. Chronic diseases such as diabetes and hypertension are on the rise. This study is funded by Texas-based Hunt Oil Company, which is exploring for natural gas in the region. The researchers stress that the health survey is an independent academic project controlled by Duke University. Medieta at the local health ministry says he'd never have the time or the resources to do such an exhaustive health survey like this on his own.

MEDIETA: (Through interpreter) This study is important because it's going to allow us to see the health of the whole population and allow us to come up with ways to make things better.

BEAUBIEN: Down the road, all the data that's collected might also help show how things like climate change, new roads or vaccination campaigns affect disease rates in this part of the Amazon basin. Jason Beaubien, NPR News, Salvacion, Peru. Transcript provided by NPR, Copyright NPR.