Pilots face dozens of obstacles, including trees and commercial and residential buildings, when landing their aircraft at Sao Paulo's Congonhas airport, the daily Folha de Sao Paulo reported Wednesday.

Citing documents obtained from Brazilian aviation authorities under the Access to Information Law in force since May, the paper said there were some 45 different obstacles, including buildings blocking the flight path of incoming planes.

The hurdles on the way to Congonhas, which lies within the city, include two hospitals and a shopping mall, the newspaper added.

Folha said all the obstacles were within a so-called "approach cone" through which planes must pass and gradually reduce their altitude to land at Congonhas, one of the three commercial airports serving Sao Paulo.

Carlos Camacho, head of air safety at the National Union of airline pilots, said the obstacles did not mean a collision risk for incoming planes but that they reduced the safety margin.

Aviation authorities said obstacles at Congonhas would be "tolerated" until they are modified to meet regulations.

Sao Paulo's Guarulhos airport, Brazil's largest, meanwhile has 28 obstacles in its approach cone, including two Assembly of God evangelical churches, commercial buildings and a supermarket, Folha said.

It said this was because Guarulhos lies in a less densely populated suburban area.