The very old apartments have lead pipes for hot water so, you cannot drink it. The new use a blend of copper and zinc that is lethal for aquarium fish. So, in general, you can only drink cold water and the key are not the pipes, instead, if the tank at your building is clean and it is covered, otherwise, pigeons can defecate on it and then parasites can be transmitted.
The water here (CABA) is low in Ca, Mg, GH, Kh (1.5) and No3 (2.5 ppm) while in Europe in general is 40 ppm.
There is esterichia Coli in the water of the river so, this is why they use Cl a lot.
You can check with your portero when was the last time they clean the tank and if it is properly covered.
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