GENEVA, November 3 — The world's drinking-water rulebook is nearly seven decades out of date on one of farming's most common pollutants, a coalition of 85 health and environmental organisations told the World Health Organization on Tuesday. In an open letter, the groups — including Greenpeace International, the International Panel of Experts on Sustainable Food Systems (IPES-Food) and the World Organization of Family Doctors (WONCA) — called on the UN health agency to include nitrate in its upcoming review of global drinking-water guidelines and to formally prioritise nitrate for full evaluation.
Source: AFP via Medical Xpress
Nitrate is a contaminant closely associated with intensive agricultural practices — it washes into groundwater and rivers from fertiliser and manure — and is considered particularly harmful to children and pregnant women. Most national governments base their own drinking-water standards on WHO guidelines, the organisations said, which is why a change in Geneva would ripple through water rules worldwide.
A limit written for one risk, in another era
The existing guideline of 50 mg/L as nitrate (11.3 mg/L as nitrate-nitrogen) was established in 1958 specifically to prevent infant methemoglobinemia, known as 'blue baby syndrome', a condition that reduces the blood's ability to carry oxygen. The letter says that level 'has not been updated in response to robust epidemiological evidence linking chronic, low-level nitrate exposure to long-term human health risks', pointing in particular to colorectal cancer and adverse birth outcomes.
'Studies now link nitrate in drinking water, at levels well below the current WHO limit, to bowel cancer and premature birth,' said Dr Pratyush Kumar, chair of WONCA's working party on rural practice, in the coalition's joint statement. Greenpeace's global project lead for agriculture, Amanda Larsson, said clean drinking water should be protected through stronger action against pollution, and that the regulatory limit should be lowered in line with current health science.
Denmark has already moved
The organisations pointed to findings published last year by an expert panel commissioned by the Danish government, which concluded that the current international standard was insufficient to protect public health. That panel recommended reducing the nitrate limit to 6.0 mg/L — nearly ten times below the current WHO benchmark — and Denmark committed earlier this year to making that reduction. The coalition argues that if one country's expert review reached that conclusion, the WHO's global guideline cannot credibly stay at a 1958 figure without a fresh evaluation.
Why this matters beyond Geneva — including in Punjab
The letter was timed to coincide with One Health Day, the WHO-backed annual observance highlighting how human, animal, plant and environmental health are connected. The question is not abstract for intensively farmed regions: where fertiliser use is heavy — Punjab's fields among them — nitrate leaching into groundwater is a long-standing concern for rural drinking-water supplies, and national limits in most countries trace back to the WHO number the coalition wants rewritten. The coalition's ask is procedural but powerful: prioritise nitrate in the review, and let the Guideline Development Group weigh the modern evidence in full.
What happens next
The WHO has not announced a decision on the letter. Its guideline values are not legally binding, but because national regulators peg their standards to them, a lower WHO value would pressure governments worldwide to tighten tap-water rules — and, campaigners argue, to act against agricultural pollution at the source rather than only at the tap.