EurEau is concerned about the draft international standard ISO/DIS 18671 (test methodologies for assessing products suitable to be flushed down a toilet and appropriate labelling). We believe this standard, if adopted in its current form, could have detrimental effects on wastewater systems and the broader water environment by encouraging or enabling the flushing of inappropriate items into sewer networks.

Wet wipes and other disposable personal care products remain the leading cause of blockages in sewer networks and wastewater treatment facilities. These blockages result in significant operational costs for wastewater operators and contribute to pollution, particularly when these items are discharged through combined sewer overflows. Over the past decade, the issue has escalated due to the marketing of products as “flushable” and the growing consumer use of all types of wet wipes.

In 2014, EurEau estimated the financial impact of inappropriate flushing in Europe to be between €500 million and €1 billion annually. By 2024, this figure has doubled, with costs now estimated at €1 billion to €2 billion per year. Despite efforts to mitigate the issue, such as the introduction of flushability standards and logos in countries like the UK and Belgium, these measures have failed to reverse the trend. Consumers often overlook packaging instructions, and the presence of “suitable to be flushed” labels can lead to the misconception that all wet wipes are safe to flush.

You can read the letter sent to ISO pdf here (170 KB) .