The levels of long-lasting toxins known as “forever chemicals” rose in a highly protected marine area after sewage discharges, researchers found.
The University of Portsmouth teamed up with the Marine Conservation Society (MSC) to test for PFA chemicals in Langstone Harbour, Hampshire, which is home to harbour seals and a diverse range of birds.
Called “forever chemicals” because they can take centuries to break down in the environment, PFAs can accumulate in the bodies of living organisms and have been linked to severe health conditions.
They are used in different products like pesticides, non-stick cookware, food packaging and cosmetics, and can enter wastewater through many day-to-day activities.
Researchers from the university’s Institute of Marine Sciences collected seawater samples before and after sewage discharges from a storm overflow at Budds Farm wastewater treatment plant, which services more than 400,000 people.
Storm overflows are designed to work as relief valves by releasing untreated wastewater into rivers or seas during periods of heavy rain to prevent sewers from becoming overwhelmed.
The Southern Water plant is by Langstone Harbour – a Site of Special Scientific Interest (SSSI) and a Special Area of Conservation (SAC).
The researchers’ findings, published in the journal Chemosphere, revealed concentrations of PFAs increased significantly after sewage discharges in the harbour.
Eight different PFA compounds were detected post-discharge, compared to just one detectable compound before the discharges, the team said.
Two banned PFA chemicals – perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) – were also found at levels exceeding annual average environmental quality standards.
Untreated sewage is already known to contain a cocktail of contaminants such as bacteria, viruses, nutrients, harmful chemicals and microplastics.
However, little information is known about the level of PFAs in sewage discharges.
This is because there are no requirements for water companies to monitor the level of contaminants found in storm overflows, the researchers said.
Co-author Dr Francesca Ginley, chemicals policy and advocacy manager at MCS, said: “These findings underscore the need for an urgent ban on PFAs from all uses where there are alternatives.
“PFAs are found in water and wildlife around the globe, from plankton to polar bears.
“These chemicals will impact us and the environment for generations to come. We need the UK Government to properly protect our environment from this preventable pollution.”
Project lead, Professor Alex Ford from the University’s school of the environment and life sciences, said: “Given how much we now know about the extent to which sewage gets discharged into our rivers and seas, it is worrying to see these contaminants elevated in a coastal environment which could take decades to break down.
“Unfortunately, it is unsurprising that these toxic compounds are detectable in our whales and dolphins.”
Elsewhere, the study found significant levels of forever chemicals in seaweed, the team said.
Samples showed the amount of one particular PFA chemical – perfluorobutanoic acid (PFBA) – in seaweed was more than 6,000 times higher than the amount found in the surrounding water.
Professor Ford said: “These seaweeds could potentially be acting as a reservoir for these forever chemicals around our coasts.
“High concentrations of PFA compounds in macroalgae might be harmful for marine life which graze on seaweeds and as a result provide a trophic link up the food chain.
“Toxicity studies in the laboratory and human epidemiological studies of those drinking PFAs-contaminated water have highlighted these chemical compounds can impact the immune, nervous and reproductive systems as well as being carcinogenic and cause birth defects.
“It is important that we get these chemicals banned as we are still seeing the impacts of persistent chemicals contaminants – like PCBs – impacting wildlife which were banned decades ago which is why it is so important we act faster.”
The team said further research is needed to understand the long-term effects of PFAs on marine food chains and to develop effective strategies for reducing their presence in the environment.
It comes as MCS campaigners call on members of the public to join dozens of green groups for the March for Clean Water in London on November 3 to demand the Government take immediate action to end the poisoning of seas, rivers and lakes.
PA has contacted the Environment Department (Defra) and Southern Water for comment.
