UK Water Industry Study Shows Success in Reducing Forever Chemicals
A long-term monitoring program reveals that source control and regulatory bans are more effective than expensive treatment upgrades.
New data from the UK water industry’s most extensive chemical monitoring initiative suggests that targeted policy and source control measures are successfully reducing the prevalence of “forever chemicals” in the environment.
The findings come from the UK Water Industry Research (UKWIR) Chemical Investigations Programme (CIP), a collaborative effort between water companies and regulators, including the Environment Agency. The program represents a comprehensive scientific response to managing hazardous substances in the water cycle.
According to the CIP3 Trend Monitoring Project, which analyzed data from 2020 to 2025, concentrations for 19 of the 20 monitored substances showed significant downward trends. These substances include lead and perfluorooctane sulfonate (PFOS), a member of the PFAS family known for its persistence in the environment.
The report indicates that national and international source control—such as product bans and phase-outs—is effectively reducing hazardous substances without relying solely on intensive treatment plant upgrades.
“The water industry isn’t the source of these chemicals, and our data shows that when there is rigorous source control, the environment heals without the need for carbon-heavy, expensive interventions from utilities,” said Jenni Hughes, strategic programme manager at UKWIR.
Hughes noted that this evidence-based approach provides a blueprint for tackling emerging compounds without defaulting to “end-of-pipe” solutions that would result in significantly higher costs for utility customers.
The monitoring project, which collected four-and-a-half years of data across England and Wales, highlighted several key success stories:
- Tributyltin (TBT): Once used in antifouling paint for ships, this endocrine disruptor has seen environmental levels plummet following a 2008 global ban.
- PFOS: Historically used in textiles and firefighting foams, PFOS concentrations in effluent are declining. However, the substance remains a challenge due to its ability to leach from legacy landfill sites into groundwater.
- Lead: Concentrations continue to drop as a result of ongoing plumbing replacements and historical shifts in manufacturing.
The only exception to the downward trend was dissolved mercury, which showed an increasing presence. Mercury enters the environment through various pathways, including fossil fuel combustion and waste incineration.
“You can’t control what you don’t measure,” said Mark Craig, UKWIR co-lead for wastewater. “It proves that for many substances, if the source control measures are in place and working as they should, concentrations in sewage effluent decline significantly.”
As the program moves into its next phases, CIP4 (2025–2030) and CIP5 (2030–2035), the framework is designed to remain agile. Chemicals will be added to or removed from the priority list based on evolving scientific and environmental evidence.
By identifying substances likely to challenge future environmental quality standards, the program allows water companies to prioritize specific catchments for remedial action, ensuring investment is directed where it delivers the highest environmental benefit.
About the Author
Jesse Jacobs is Assistant Editor of EPOnline.com.
