Health safety watchdogs have warned against depending on water filter jugs to purify water, saying that they were of little benefit.
A report by the Agence Nationale de Sécurité Sanitaire (Anses) said many of the jugs did, indeed, reduce the smell, taste and concentrations of chlorine, lead and copper in tapwater but had very varied results in cutting calcium to reduce water hardness and in reducing nitrates.
With a million jugs and 15m filter cartridges sold each year, Anses had doubts on their worth – with deputy director general Gérard Lasfargues saying manufacturers’ claims of effectiveness should be tested regularly and the updated verifiable results should be shown on the packaging.
Filter jugs are used by 20% of households but would not turn undrinkable water into pure water and Anses said manufacturers should have another look at the materials used in the filters themselves as they could leave traces of contaminants such as silver, sodium, potassium and ammonium ions.
The agency also said the filters could lower the acidity of the water and “alter its microbiological quality” but said its tests did not show a risk to consumers.
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To get the best use out of the carafes, the agency said users had to clean them properly, change the filters every month, not to use warm water and to keep the filtered water in the fridge and never leave out in the open, plus use the water within 24 hours.
It added that their major benefit was to get rid of the taste of the chlorine used to purify the water.