quality standardReading time:
In all cases, water delivered to the consumer by the mains distribution system must have undergone processing to render it "potable", i.e. ensuring that it satisfies current regulations applicable to water intended for human consumption, even when Man only absorbs a small amount direct. In effect, a dual distribution system is not financially viable: one water system delivering water intended for human consumption and a second system delivering water of an inferior quality intended for other applications, without taking into account the major risks caused by faulty or cross-connections.
Therefore, water has to be treated each time any one of the analytical parameters exceeds the standards applicable in the country considered. For each parameter, the WHO (World Health Organisation) has set recommendations that can be adjusted to suit each country according to its health and economic circumstances, thus enabling each country to establish national statutory standards.
In the European Union, the quality of drinking water has been set by a directive that each member State is obliged to transpose into its national legislation. The original 1980 directive was transposed into French law on the 3rd January 1989; it defined guide levels and maximum admissible concentrations applicable to 64 parameters; only the second concept ( MAC ) was included in a revised directive (98/83/CE) published on the 5th December 1998 in the European Community Official Gazette (ECOG) and transposed into French law by order 2001-1220 of the 20th December 2001. Current standards in France are governed by decree 2007-49 of Janaury 11th, 2007.
This latter directive established a certain number of parametric values (some of these would be brought into compliance over a period of time). Since 2000, the evolution in standards has namely concerned consumer health: some parameters that featured in the original directive have been deleted and others amended to become more stringent (e.g. Sb, As, Pb, Ni, HPA…); others will have been included for the first time (e.g. acrylamide, B, Ba, benzene, bromates, THM, pesticide metabolites, etc. to which France has added chlorites (residue of oxidation by chlorine dioxide) and microcystine (one of the toxins produced by numerous cyanobacteria). Additionally, this directive clearly expresses the concept of compulsory compliance with standards at the consumer’s tap, thus allowing for potential water quality deterioration as it travels through the mains.
Due to the frequent changes to standards in this field, the reader is referred to the most recent officially updated figures (Official Gazettes and national ministers for Public Health; WHO Geneva Publications and the WHO website).
Note: In France, the parameter values published have been renamed, according to the case, limit or quality references.