Rotterdam: Europe has finally put a strategy behind a worry it has carried for years. Early this summer the European Commission presented its long-awaited Water Resilience Strategy, a framework meant to pull together the bloc’s scattered responses to drought, flooding and pollution into something resembling a plan. At its centre sits an adversary that does not break down on any human timescale: the family of synthetic compounds known as PFAS, the so-called forever chemicals that have seeped from factories, firefighting foams and consumer products into soil, rivers and drinking water across the continent. The scale of the contamination is what makes the numbers frightening. The Commission’s own estimates put the annual cost of cleaning up PFAS pollution somewhere between 5 billion and 100 billion euros, a range so wide it amounts to an admission that nobody yet knows how deep the problem runs. Water utilities alone could face up to 18 billion euros a year in extra treatment costs to strip the chemicals out of supplies. A public-private partnership on detection and clean-up is meant to launch this year, an implicit acknowledgement that public budgets cannot shoulder the bill alone and that the industries which profited from these compounds should help pay to remove them. Regulation has been tightening in parallel. Since the start of the year member states have been obliged to monitor PFAS levels in all drinking water and keep them within newly set limits, turning what was once a specialist concern into a routine obligation for every water authority. The tougher rules protecting water bodies more broadly have also come into force. In mid-June the environment commissioner convened a high-level dialogue on the pollution, a sign that the file has climbed high enough on the political agenda to warrant direct ministerial attention rather than technical committees. The harder decision is still pending. The European Chemicals Agency is due to deliver its final scientific assessment of a sweeping restriction by the end of the year, after which the Commission will table a proposal aimed at choking off PFAS emissions at source. That is where the politics turns fierce. Manufacturers argue that some of these chemicals are irreplaceable in medical devices, semiconductors and green technologies, and that a blanket ban would hobble the very industries Europe is trying to grow. Health and environmental groups counter that every year of delay adds to a contamination burden that future generations will pay to remove, at costs that dwarf any near-term industrial inconvenience. Between those poles the strategy tries to hold a difficult line, cleaning up what has already escaped while arguing over how tightly to close the tap. The uncomfortable truth running through the whole exercise is that forever chemicals earn their name. Whatever the Union decides, the compounds already in Europe’s water will still be there long after the current officials, and their critics, have left the stage.