1987 1996 series
In the 2012 TV series, the character Xever Montes (Fishface) is Brazilian, and during his backstory flashback in the Baxter's Gambit, a young Xever is seen walking across the crowded streets of a town in Brazil, which in the Nickelodeon's Teenage Mutant Ninja Turtles magazine (published by Panini Comics) is revealed to be São Paulo, the biggest city in South America.
In the 2016 film Out of the Shadows there are scenes taking place at the Iguazu Falls. There the turtles jump from an aeroplane moving from the USA to Brazil onto another aeroplane moving in the opposite direction and fight against Bebop and Rocksteady to retreive the last piece of the transdimensional portal device.
The Iguazu Falls are waterfalls of the Iguazu River on the border of the Argentine province of Misiones and the Brazilian state of Paraná. The falls divide the river into the upper and lower Iguazu. The Iguazu River rises near the city of Curitiba. For most of its course, the river flows through Brazil, however, most of the falls are on the Argentine side. Below its confluence with the San Antonio River, the Iguazu River forms the boundary between Argentina and Brazil.