Guanabara Bay surrounds a broad metropolitan and industrialised area i
n Brazil. The trends in faecal pollution between 1980 and 1990 were in
dicated by data of coliforms from different institutions. There was an
increase from 1.3 to 2.9% per year. The available sewage treatment sy
stems now result in contamination (faecal coliforms values from 10(3)
to 10(8).1(-1)) well above the permitted standards, endangering the sa
nitary quality.