Water filter jugs are domestic water treatment devices intended to be used exclusively with drinking water (DW). They are therefore not designed to make non-potable water potable. The improvement of the organoleptic properties of water (chlorine taste in particular) and the removal of limescale and certain metals such as lead are some of the claims made by manufacturers of water filter jugs. As many as 20% of French households may be equipped with a water filter jug.
Following reports to the Directorate General for Competition, Consumer Affairs and Fraud Control (DGCCRF) about undesirable substances being released into the water by these devices, questions being raised about their safety and effectiveness, and articles published in the press, ANSES issued an internal request to assess the safety and effectiveness of water filter jugs.
The Agency’s expert appraisal focused on devices used at home (water filter jugs and bottles) with DW supplied at the tap, and not connected permanently to the DW supply system. Thus, sport water filter bottles that are intended for a single user and can be raised to the mouth, under-the-sink or tap-mounted filters that are permanent systems, and filtration systems marketed for disinfecting water in the home in an emergency situation or intended for travellers, were excluded from the scope of the expert appraisal.
The Agency’s recommendations
The use of water filter jugs can lead to various contaminants (silver ions, sodium, potassium, ammonium) leaching into drinking water, as well as a decrease in pH, and even a deterioration in the microbiological quality of the water. However, the data currently available are unable to demonstrate a risk to consumer health.
Furthermore, although the available results show that most of the water filter jugs comply with the standards’ recommendations on improving odour and flavour, and reducing concentrations of chlorine, lead and copper, these data cannot be used to assess the actual effectiveness of all water filter jugs on the market. The Agency considers that the effectiveness claims should be systematically verified by standardised tests, and the observed reduction percentages for the tested parameters should appear on the packaging and/or user leaflets for the filter cartridges.
The Agency is formulating proposals to improve the current standardised test protocols relating to the safety and effectiveness of water filter jugs. It recommends that preliminary laboratory tests be undertaken to verify the feasibility of its recommendations.
The Agency insists on the need to inform users of restrictions or precautions for use in light of the observed effects on the quality of filtered water. It therefore recommends that users:
- comply with the user instructions and any restrictions or precautions for use: cleaning of the jug, regular replacement of the cartridge, contact between the filtered water and certain metal or ceramic utensils, especially when the water has been heated, feeding of infants, consulting a doctor for people following restricted diets, in particular those low in sodium or potassium;
- keep the water filter jug and its water in the refrigerator and consume the filtered water promptly, ideally within 24 hours of filtration;
- pay special attention to effectiveness claims for water filter jugs provided by manufacturers (presentation of parameters for which compliance with the standard has been verified).
The Agency recommends that filtered water should comply with the quality limits and reference values defined in the regulations on DW. Concerning silver in particular, although the concentrations observed in the filtered water do not exceed the guideline for water of 100 µg/L established by the World Health Organization (WHO), the Agency recommends that this value be examined in light of recent toxicological data, and stresses the need to consider the risk/benefit ratio of using silver for this type of purpose.
Lastly, the Agency reiterates that the materials used in water filter jugs, bottles and cartridges must comply with the regulations on food contact materials (FCM), and that manufacturers have an obligation to ensure that FCMs do not leach any elements into the filtered water in quantities likely to be harmful to human health, cause an unacceptable change in the composition of the filtered water, or alter its organoleptic properties. In addition, the Agency draws consumers’ attention to the products available for sale online, which may not comply with the European regulations, and emphasises the need for the public authorities to monitor the compliance of these products.