The safety of drinking water is facing renewed scrutiny, with 85 international health and environmental organisations urging the World Health Organization (WHO) to reconsider its decades-old nitrate limits amid emerging concerns over long-term health risks.
According to an AFP report published by ETHealthworld on November 3, the coalition, which includes Greenpeace International and the World Organization of Family Doctors (WONCA), has called on WHO to prioritise nitrate in its upcoming review of global drinking water quality guidelines.
The concern centres on the existing WHO limit of 50 milligrams of nitrate per litre, established in 1958 primarily to prevent methemoglobinemia, commonly known as ‘blue-baby syndrome’. However, campaigners argue that this benchmark no longer adequately reflects contemporary scientific evidence.
Recent epidemiological studies have linked prolonged exposure to even relatively low nitrate concentrations with increased risks of colorectal cancer, premature births and other adverse pregnancy outcomes. Children and pregnant women are considered particularly vulnerable.
Nitrate contamination is closely associated with intensive agriculture, including synthetic fertiliser use and livestock farming, raising concerns about pollution of groundwater and surface water. The coalition warns that hundreds of millions of people worldwide could be exposed to elevated nitrate levels.
Adding weight to the demand, a Danish government-commissioned expert panel recommended lowering the permissible limit to 6 milligrams per litre. Denmark has committed to moving towards this stricter standard.
The appeal highlights a growing public health challenge: drinking water regulations must evolve alongside scientific understanding. For WHO, the proposed review could become an important step towards strengthening global water safety and preventing avoidable disease.
WHO’s Guidelines for Drinking-water Quality retain a nitrate guideline value of 50 mg/L, intended to protect against methaemoglobinaemia (blue-baby syndrome), particularly in bottle-fed infants. Its 2026 guidance also explains that the guidelines provide the scientific basis for countries to develop their own drinking-water standards.
References: World Health Organisation, AFP, ETHealthworld
