Columbia subject headings:
Harvard subject headings:
Drinking water--Health aspects--Brazil--Belém.
Water quality--Health aspects--Brazil--Belém.
Water-supply--Health aspects--Brazil--Belém.
Princeton subject headings:
Water quality--Brazil--Belém.
Water use--Brazil--Belém.
Water-supply--Brazil--Belém.
Water-supply--Environmental aspects--Brazil--Belém.