2° YEAR I.G.E.A.
According to the law mineral water must come from
underground natural water sources protected from
contaminations and it must be pure from bacteria. Adding
carbon dioxide and eliminating iron and sulphur are allowed.
In order to be considered as drinkable, tap water
must be colourless and odourless, clear and fresh.
HARDNESS
NITRATES
PH
ALKALIS
NITRITES
H2S (Sulphuric Acid)
Hardness, which is expressed in French degrees (°F), indicates the
presence of calcium and magnesium in water, that is if water is more
or less calcareous.
Following CEE directives, water with hardness inferior to 30 °F are
considered as “sweet", that is containing little limestone.
Hard water springs especially from calcareous soils, while in soils
with a higher percentage of granite, slate or green-sand, the quality
of water tends to be sweeter.
At high temperatures hard water leads to the formation of
limestone (as it happens in water pipes or in the case of some
particular electrical appliances); this causes higher energy
consumption, since limestone is a bad heat conductor.
L'acidità è una delle proprietà più importanti dell'acqua. L'acqua è un
solvente per quasi tutti gli ioni. Il pH serve da indicatore che confronta
alcuni degli ioni più solubili in acqua.
Il risultato di una misura di pH è determinato da un confronto tra il
numero di ioni H+ ed il numero di ioni ossidrile (OH-). Quando il numero
di ioni H+ è uguale al numero di ioni OH-, l'acqua è neutra, cioe' ha un pH
di circa 7.
Il pH dell'acqua può variare fra 0 e 14. Quando il pH di una sostanza è
superiore a 7, è una sostanza basica. Quando il pH di una sostanza è
inferiore a 7, è una sostanza acida.
Capacity of water to neutralize an acid or a
base, so that this pH doesn’t change
Nitrates are compounds made of nitrogen (N) and oxygen (O).
Man takes in nitrates mainly through drinking water and vegatables.
Nitrates are harmless. Under some circumstances (for ex. in case
of long conservation, heat, acidic pH ) they can turn into nitrites,
which have harmful effects.
The in-take of nitrates should therefore be limited as much as
possible.
Nitrites are compounds made of nitrogen (N) and oxygen (O). Under
particular circumstances nitrates turn into nitrites.
This reaction can take place in the soil, in drinking water, in food
and the human body.
Nitrites are toxic substances; binding to haemoglobin (blood protein
carrying oxygen to body tissues) they hinder oxygenation.
At greater risk are newly-born babies who can have breathing
problems and in extreme cases asphyxiation due to poor
oxygenation.
Sulfate is one of the main elements dissolved in the rain.
High sulfate concentraions in drinking water can have a
laxative effect if they are joined with calcium and
magnesium, the two most common elements of hardness.
The bacteria which attack and reduce sulfates make up
hydrogen sulphide gas (H2S).
Why should we drink tab water again ?
The answer is simple and articulated at the same time.
Let’s clear any doubt: taP water is controlled and safe.
Of course, in case of an excessive use of chlorine it might be
organoleptically unpleasant; in this case just follow this simple tip:
since chlorine is volatile, you simply need to let tap water rest in a jug
for about 10 minutes so that chlorine can evaporate; try!
Drinking water is safe because it must comply with lots of hygenic
measures. The guarantee of its drinkability is sure: if tap water flows
out of our home pipes, it’ s safe because it is tested as drinkable!
Should just one criterium not be respected, the Mayor of the Town is
compelled to pass a bill of not drinkability: a guarantee for our health.
DRINKING WATER
MINERAL WATER
HARDNESS
15 - 50 °F ( French
degrees )
Foreseen parameter but
without limitations
PH
6,5 - 8
Foreseen parameter but
without limitations
NITRATES
50 mg/l
45 - 10 mg/l
NITRITES
0,1 - 0,5 mg/l
0,02 mg/l
H2 S
250 mg/l
Foreseen parameter but
without limitations