Patrick Byrne - Pioneering methods for identifying the sources of forever chemicals in our water
Professor Patrick Byrne is a hydrologist and a pollution scientist. His expertise centres on inorganic and organic chemical pollution in rivers, ground water and the coastal zone. He has worked extensively on understanding mine pollution sources to support remediation strategies across the UK, USA, Canada, South Africa, China, and the Philippines. Most recently his research has focussed on understanding the sources of ‘forever chemicals’ in the environment, and how they are transported from the land to the oceans.
He is working with the UK Environment Agency (EA) and environmental consultants to determine the most effective ways to design clean-up strategies for water pollutants, stopping the problems upstream in the most cost-efficient ways. He is a well-regarded science communicator and has recently articulated the importance of his work addressing water pollution in a podcast and series of articles with The Conversation and through a BBC Panorama documentary.
Global pollution legacies
Forever chemicals, also known as per- and polyfluoroalkyl substances (PFAS), have been detected in almost all surface water and ground water worldwide. These substances are waterproof, oil-resistant, and can withstand very high temperatures. This makes them very useful to us, but also almost impossible to destroy when they escape into the environment, hence the term 'forever chemicals'.
Patrick explains there is overwhelming evidence that PFAS are harmful to humans. Three compounds are directly linked to kidney and testicular cancer and there is strong evidence linking PFAS as a group of chemicals to reduced fertility, abnormal foetus development, obesity, early onset of puberty, and reduced response to vaccines. This has led the European Union to call for a total ban on the entire group (thousands) of chemicals. Patrick warns that while we eventually need to wean ourselves off these chemicals, they are used in almost all modern industrial and manufacturing processes. They are in our electronic items, clothes, food packaging, cookware, carpets, furniture, make-up and cosmetics, and even our food and drinking water. PFAS are also critical in the production of hydrogen fuel cells, which are focal to national strategies for sustainability. So, it will take years or even decades to develop PFAS alternatives and to substitute them into global industry and manufacturing.
The sources of PFAS to the environment are well known. PFAS enter our sewage systems from our homes, reaching treatment plants where they cannot currently be removed. And so, every 'clean' water discharge from a wastewater treatment plant in the UK contains PFAS. Our waste products that do not go down the drain usually end up in landfill. We know water draining landfills contains high levels of PFAS. Airports and military bases are another significant source of PFAS, due to the use of PFAS fire-fighting foams, and agriculture is also a source due to the use of PFAS pesticides and traditional application of PFAS-rich sludges on agricultural land. But Patrick argues the biggest source of PFAS is us, humans, as we are addicted to products only possible using PFAS.
Exposing hidden pollutant sources
In the UK, there are thousands of PFAS contaminated sites and so the biggest problem facing the government and the environmental regulators is where to start. As rivers are the main pathway transporting PFAS from land to sea, Patrick argues that identifying and quantifying sources to rivers is crucial to disrupting the PFAS cycle. This work isn’t straightforward due to the complexities of sources and how they release PFAS, and the technical challenges in measuring how much PFAS contamination enters and moves through rivers.
Patrick is using innovative research methods that challenge traditional methodologies used to locate and quantify pollutant sources. Much of Patrick’s work focuses on analysing quantities of PFAS (the 'PFAS load') that enter rivers, rather than focussing just on concentrations. Concentrations give us a measure of how much PFAS is present in our sample, whereas the total PFAS load quantifies how much is moving through the river across space and time, allowing him to see where most PFAS enters rivers and to identify the largest emitters. Measuring PFAS loads is very challenging however, so Patrick is using state-of-the-art autonomous unmanned survey vessels equipped with high-tech survey equipment that can be deployed anywhere in a river, at any time.
Patrick speaks of critical financial barriers that are involved in studying the presence of PFAS. Sample analysis requires specialist instruments that are expensive to obtain and tapping into small internal LJMU research funding streams has been invaluable in getting the research off the ground. Today, Patrick’s PFAS research is funded by the Environment Agency (EA) and through collaborations with environmental consultants. He is working closely with Dr Lauren Mullin, an analytical chemist in PBS, to continue developing LJMU advanced capability in PFAS analysis.
Informing environmental regulatory bodies to prioritise national policies and actions
Patrick is working alongside the EA to increase the impact of his work moving forwards. Together, they have revealed globally significant volumes of PFAS flowing into the River Mersey and the Irish Sea, a message which hits close to home. A critical challenge facing the EA is how to prioritise PFAS contaminated sites nationally for intensive monitoring and ultimately clean-up. Patrick is working with the EA on new ways to interrogate their national monitoring data to identify regional and river catchment PFAS hotspots. At the scale of PFAS contaminated sites, Patrick works with the EA and consultancy partners to figure out the science of PFAS mobilisation: where, when and how PFAS enters rivers. This process understanding is critical to allow remediation scientists to design effective clean-up strategies and technologies and make decisions about how best to allocate resources to address problems at source.
Next steps: Prioritising remediation and measuring recovery
Importantly, his broader multi-disciplinary approach incorporates both biogeochemistry and hydrology to inform interpretation of measurements, providing a critical link needed to translate these findings into real world remediation strategies. Patrick expands on how this might work, he says 'if we know how much is coming from all the different sources, we can rank them, and we can prioritise and then government and regulators know where most contamination is coming from, and by remediating that source, they can actually measurably reduce the amount going into the rivers, and they can report on that.'
Combined with making changes to the clean-up, Patrick is working on making changes to how we monitor it and understand the scales of our success. Alongside developing an understanding of how PFAS is mobilised within the environment at smaller scales, Patrick says recovery for water bodies must be measured using long-term metrics of change. Both one-off ecological surveys and simple quarterly monitoring will likely not evidence these changes immediately after remediation, instead investment in viewing these changes over longer timescales is needed.
Patrick’s research is helping to turn complex chemical measurements into practical strategies, moving towards lasting change that promotes recovery of rivers, ecosystems and public health.
Professor Patrick Byrne spoke with Elise Fox