How to purify tap water. THE methods to purify our tap water they are many, with very different costs and recommendations that vary according to individual cases and needs. Let's see an overview and our recommendations.
The first important premise is that the quality of thewater supplied by the aqueducts Italians is controlled under the provisions of Legislative Decree 31/01, issued in implementation of Directive 98/83 / EC, which defines the withdrawal points, the parameters to be determined and the legal limits.
Art. 7 of the decree establishes that i checks on the water must be of two types:
- Internal controls, borne by the manager of the aqueduct, to monitor the purification process and the hygienic safety of the water
- External controls, charged by Food Hygiene and Nutrition Services (SIAN) of the territorially competent ASLs (Local Health Authorities)
These checks ensure that the water supplied by the aqueduct is of good quality and therefore drinkable without the need to use any purifier.
However, what the aforementioned controls CANNOT guarantee is the quality of the water supplied by the individual taps as this is affected by the quality of the condominium pipes.
The main risk is related to the pipes of old buildings which can release lead precisely because they are made with this material. The lead it is a material toxic and the European legislation of 2013 sets the maximum limit tolerable in drinking water in 10 micrograms per liter.
A other dangerous water contaminant as a carcinogen it isasbestos which may be present in the water in the form of very small suspended particles (<1 micron).
The presence of these contaminants in Italy is extremely rare but some cases have been found.
Reverse osmosis purification plants
The purifiers that give greater guarantees in order to remove toxic residues such as lead and asbestos are the reverse osmosis purification plants, used in hospitals, in case of interventions in areas affected by natural disasters that have polluted the water and by companies that produce drinks on an industrial scale: Coca Cosa, beer, Fanta, Gatorade, etc.
Some low-cost natural waters for sale in supermarkets are nothing more than “tap water” treated with reverse osmosis purification systems!
However, it is not certain that buying areverse osmosis system is the best way for final consumers.
First of all for the factor price, as the cost of a reverse osmosis purification plant and of at least 250 Euros, to which the periodic expense for the purchase of filters must be added.
In addition, reverse osmosis systems could depleting the water of important mineral salts, such as calcium and potassium, which instead have a beneficial effect on health with a counterproductive effect, especially in the long run.
However, some manufacturers of domestic reverse osmosis systems respond to both criticisms with two answers:
1) to avoid having to spend considerable sums to purchase the system, offers are available in which the system is installed free of charge against payment of a maintenance fee.
2) the most modern domestic reverse osmosis systems have adjustable filters that allow you to adjust at will "the impact of the purification action".
Activated carbon tap filters
Another possibility to "purify" the water from our tap is constituted by activated carbon filters. This is the technology used by the jugs that are enjoying growing success.
Among the most sold and appreciated you will surely know the Brita carafe, available online for less than 20 Euros.
This kind of activated carbon filters, they permanently absorb metals such as lead and copper and act on water quality in terms of taste and perception, making it clearer, reducing the amount of limestone and improving its flavor.
This is a practical solution that allows you to save on the purchase of bottles of mineral water, while always having to bear in mind that in this case too the filters must be replaced periodically and that the carafe must be kept clean.
As reported in the instructions for use, to ensure the proper functioning of the Brita carafe it is necessary to replace the filter every four weeks, or upon reaching 100 liters of filtered water.
Assuming the consumption of 1 liter of water per person per day, in a family of 4 (the recommended water consumption per person is higher but in most cases it is also consumed outside the home, in the office or at school for example) , a filter therefore has a useful life of approximately 1 month.
Considering that a pack of 12 filters is sold for 49.9 Euros and that 12 filters are enough to meet the needs of a family of 4 for a whole year, the savings compared to the purchase of bottles of mineral water is confirmed and real.
THE activated carbon filters they can also be installed directly on the tap instead of inside a carafe. For example, this is the solution proposed by Acquasan: a filter + 3 cartridges for sale online at 31 Euro.
THE aerator filters they are the simplest and least expensive solution to retain larger impurities and in particular limestone.
Their action is exclusively "passive" (therefore they do not incorporate any active filter) but their use is still useful and above all extremely economical: 4 filters can be purchased online for less than 10 Euros.
I hope I have given you a comprehensive overview of the different options for purify tap water of your home and I refer those interested in sparkling water to these other two articles:
– How to gass water
– Free sparkling water in Milan