depends on whether its contaminated or not, there are UK standards and the world health org standards which set the legal limits on what should be in our drinking water and what shouldn't be in the water. i think it also depends on your water source and how hard your water is.
The usual level is anywhere from 0.2 to 1 mg per liter.
W.H.O. guidelines set forth a conservative maximum allowable level of 5 mg/liter, though you can readily taste the chlorine at well below that amount.
almost zero. here in CH it is ca. 3.3 milligrams per liter. Just read on the bottle of natural (!) mineral water from your region.
between 0.5 to 0.9 ppm
0.5-0.9
60 -100 ppm is the currently acceptable hardness level for drinking water in US and Canada.60 -100 ppm is the currently acceptable hardness level for drinking water.
0.o15 ppm
0.1
Between 50 ppm and 300 ppm is safe. Better below 100 ppm.
5 ppm
it should be below 3.5 ppm
Depends what you call "too much". The current acceptable limit is now 3ppm, but I have seen people drinking with over 8 ppm and not being bothered by it.
It depends what substance there are 10 parts per million of.
5 mg/L
This concentration of phosphates (1 000 ppb = 1 ppm = 1 mg/L) is without importance for drinking water.
1-2ppm
ppm by volume is "parts per million" by volume as opposed to ppm by weight. ppm by volume and ppm by weight are not the same thing It has been suggested that the drinking water in West Hampshire be adultery with 1 ppm by volume of fluoride. This is an example of ppm by volume