Sir, – Last week’s judgment by the European Court of justice emphatically rejected Ireland’s claim that the exceedance of the permitted parameters of trihalomethanes (THMS) in Irish drinking water did not constitute a potential risk to human health (“Nearly 240,000 people across Ireland drinking water with elevated toxin levels, latest figures show”, News, January 26th).
The Irish claim was first made in a joint 2012 document between the Environmental Protection Agency (EPA) and the Health and Safety Executive (HSE) in response to the complaint we had filed with the European Commission in September 2011.
THMs are volatile chemical compounds that form when organic particles such as sediments or plant material reacts with chlorine disinfectant at treatment plants.
Our legislation requires the consumers to be notified if the water is a potential danger to human health in order that they may take simple measures to address the contamination – here, inexpensive activated charcoal filters on a tap or house supply, for example, or recommendations to avoid dishwashing in confined spaces, prolonged showering, steam rooms, hot tubs, and swimming pools.
Ireland’s position remained that they did not have to notify the consumers as it was not a danger to public health.
This Irish claim was finally roundly condemned by last week’s court judgment: “In the present case, the failure to comply with the parametric value set for THMs constitutes, by definition, a potential danger to human health, since water that does not meet that minimum requirement cannot be considered to be wholesome and clean”.
Irish Water states that of the supplies identified in this court case all but a few have been addressed. The Department of Housing assured us the case findings “refer to the historical position in September 2020 and that considerable progress has been made since then to the water supplies concerned in this case”.
In fact, the EPA Quality of Drinking Water in Ireland 2023 report records 235,000 people consuming THMs in 23 public water supplies, up from 109,000 people in 19 supplies in 2021, an increase of 115 per cent in two years. The report calls this “unwelcome”.
The list includes sizable supplies such as Limerick city (serving almost 115,000 people) and the Barrow supply in Kildare (over 81,000 people). These are two of the eight supplies on the EPA’s remedial action list that do not even have a plan or date for plant upgrade or improvement (“to be submitted by Uisce Éireann”).
Ireland is particularly vulnerable to THMs due to 85 per cent of its drinking water coming from surface sources, the presence of peat, shallow topographical slopes and higher than average rainfall. Recent research indicates that climate change’s increased frequency and intensity of storms may be contributing to a rise in trihalomethanes as more organic matter is flushed into our drinking water.
It is now 12 years since we first raised the issue of trihalomethanes in drinking water.
Can we now agree that this is a critical issue that demands immediate and decisive action to safeguard public health and ensure the safety of our drinking water? – Yours, etc,
TONY LOWES,
Friends of the Irish Environment,
Eyeries,
Co Cork.