Gold turned Itaituba from a river settlement into a boomtown. Through the mid-1980s and into the early 1990s the garimpos of the Tapajos valley ran flat out, and by some estimates more than 500 tonnes of gold came out of the region in that period. The town could not be reached easily by road, so it was reached by air: at the height of the rush the airstrip logged something like four hundred takeoffs and landings a day, most of them small single-engine aircraft shuttling men, fuel, rice and mercury out to clearings in the forest and bringing metal back. Air taxi operators still fly to mining camps from the same field. When the easy gold thinned out in the early 1990s the town diversified into cattle, timber and cement from local limestone, but nobody in Itaituba talks about the boom in the past tense, because the dredges never actually stopped.

Garimpo gold is separated with mercury, and mercury does not stay where it is put. It washes into the Tapajos, bacteria convert it into methylmercury, fish accumulate it, and people who eat fish accumulate it in turn. The Munduruku, whose territory covers a vast stretch of this river basin, eat fish nearly every day. In 2021 researchers from the Oswaldo Cruz Foundation reported that six in ten people tested in the Sawre Muybu Indigenous Land carried mercury above the World Health Organization reference level; in the village of Sawre Aboy the figure reached 87.5 percent of participants. These are not abstract exposures. Fiocruz teams have documented neurological and developmental effects in Munduruku children who have never been anywhere near a mining pit. The gold left. The mercury stayed, in the river, in the fish, and in the bodies of the families who depend on both.

Two large Indigenous territories reach into the municipality. The Munduruku Indigenous Territory, 2,382,000 hectares, was established in 2004. The Sawre Muybu territory took far longer. Funai first began the demarcation process in 2007; when it stalled, the Munduruku went out in 2014 and marked the boundaries themselves, posting signs and pushing miners off the land. A Funai study concluding the area was Munduruku land helped persuade Ibama to suspend and then, in August 2016, cancel the environmental licensing for the Sao Luiz do Tapajos dam, a project that would have flooded a good part of it. On 25 September 2024, after seventeen years, Justice Minister Ricardo Lewandowski signed the declaratory order recognising 178,173 hectares as Sawre Muybu. The final presidential ratification has still not been signed. Another dam, Jatoba, remains on the planning maps.

Across the river from the town centre lies Miritituba, a district that was a quiet riverside neighbourhood a generation ago and is now one of the busiest grain transfer points in the Amazon. Soybeans from northern Mato Grosso come up BR-163 for something like a thousand kilometres, and at Miritituba they are tipped out of trucks and into barges bound downriver for Santarem and the Atlantic. Cargill moved more than three million tonnes through its terminal here in 2023; Bunge and Amaggi's operation moved slightly more. In harvest season roughly fifteen hundred trucks a day pass through. The pattern is the same one the gold established, only heavier: something valuable arrives from somewhere else, changes hands at Itaituba, and leaves. The people who live along the Tapajos watch it go past.

None of this has cancelled the ordinary life of the place. Itaituba's biggest celebration is the feast of Nossa Senhora de Sant'Ana, the town's patron, held over the first half of July and closing with a Cirio procession on the 26th. July is also when the water drops and the sandbanks emerge, and the town's beaches fill up with families. West of town the Amazonia National Park, created in 1974 and covering more than a million hectares, begins about 50 kilometres out along the Transamazonica; the first waterfalls at Sao Luiz do Tapajos are a day trip. Slow boats to Santarem take fourteen to seventeen hours and go once a week; fast boats do it in seven and run most days. For a place so thoroughly wired into global commodity markets, Itaituba still keeps a river town's schedule.