PCBs: Forever chemicals – what lies beneath

Are gaps in regulation and monitoring allowing dumped forever chemicals to contaminate our land, rivers and coastal waters – even more so with the storm bursts that come with climate change? Karen Thomas reports from Wales

On a sunny spring morning, there is nothing odd about this quiet corner of the Rhondda Valley, South Wales. Narrow lanes wind through farmland, sheep and cattle penned in behind tall hedges. But the sleepy landscape masks a dirty secret – one that climate change could unearth with deadly consequences for wildlife, people and places.

Paul Cawthorne parks in a layby near Maendy, a former stone quarry. We clamber over barbed wire, push through nettles and briars and join a newly gravelled track winding down the hillside.

The gravel is dotted with fresh sheep droppings. Cawthorne points out fragments of rusted metal and mysterious lumps of red, rusty orange and dirty white material.

Exeter lab tests confirm that material collected from the site in January contains “above background levels” of polychlorinated biphenyls (PCBs).

We cross a small, mud-locked stream to enter the field beyond the site. Our wellies sink into the mud. They come away coated with a sticky orange sheen like bottled palm oil. The stream also has a sickly Lucozade hue.

Maendy was capped in 2011 to contain buried chemicals and hazardous waste transported in the sixties and seventies from Monsanto’s Newport plant – perhaps as much as 6,000 tonnes a year. Cawthorne believes it’s the UK’s most contaminated site.

The site flooded in January, he says, increasing the risk that long-buried toxins leach into the soils or flow downstream in stormwater into the River Ely.

PCBs have cumulative effects on human and animal health, becoming less safe over time. Without more systematic, stringent testing, we cannot determine the quantity of buried forever chemicals and how, combined, they affect the health and wellbeing of people and wildlife.

Cawthorne urges Natural Resources Wales and the Environment Agency in England to test sediments – as well as water quality – at all sites linked to buried forever chemicals, including Maendy and its sister quarry, Brofiscin. “The complete lack of enthusiasm for testing sediments for PCBs is absolutely perplexing,” he says.

Until we know the quantities and combinations of legacy pollutants, we cannot determine their risks to our soils, waterbodies, people and wildlife – now and as climate change brings more frequent, intense storms and flooding.

Dirty secrets

Named for their rivers that flow north to south, the South Wales valleys are fingers meeting on coastal plains that form palms at Swansea, Cardiff and Newport. Maendy and Brofiscin sit on the watershed above the rivers Ely and Taff.

In the sixties, chemical multinational Monsanto produced PCBs in Wales, at Newport and Ruabon. Chemical plants pumped out PCBs back then. PCBs were a 20th century wonder material, used from paints to pesticide extenders and to protect and stabilise electrical, heat transfer and hydraulic equipment.

But in 1968, 1,900 people in western Japan fell sick and 539 died in a mass poisoning traced to rice oil contaminated with PCBs. Soon, scientists established links between PCBs, cancers, endocrine and reproductive disorders, birth defects and other deadly side-effects for people and for wildlife.

The US banned production in 1979. The UK followed in 1986. In 2001, the Stockholm Convention banned PCBs, among a Dirty Dozen of highly persistent and toxic chemicals.

UK waste disposal was haphazard until the 1972 Deposit of Poisonous Waste Act came in. Before this, many firms hired third parties to dispose of their chemical waste. And that’s why deadly industrial chemicals lie buried in unknown quantities in at least 11 sites in Wales and England.

Wales had a PCB-linked public-health scare in 1967. A farmer whose land borders Brofiscin called his vet about a calf born with deformities. The vet brought in the National Farmers’ Union. Investigations by The Western Mail and Sunday Times Insight team linked deaths and deformities in local livestock to buried toxic waste.

The firm that disposed of Monsanto’s waste paid undisclosed compensation to affected Rhondda farmers. In 1973, Pontypridd MP Gwynmor John asked parliament how the Welsh Office was testing local water and milk supplies for PCBs.

One outcome was that – unlike Maendy and the other dumps linked to PCBs – Brofiscin is designated a special site under Part 2A of the 1990 Environmental Protection Act. Unlike Maendy, Brofiscin stands on limestone. Special site designation requires NRW – not the local authority – to manage this contaminated land.

Testing gaps

Maendy is a much larger dump than Brofiscin. It’s the risks linked to the PCBs buried there that exercise Cawthorne. The mild-mannered Shropshire vicar is an unlikely caped crusader. But he wants NRW, the Environment Agency and waste-management firm Veolia to evaluate and test for legacy PCBs far more rigorously.

What testing there is focuses on water quality. Answering an FOI request, NRW supplied data for 1981-2018 for water-quality testing for Caerphilly district council area. Those tests revealed PCB levels ranging from 0.001microgram/litre to 1,494.1 microgram/litre. The Environment asked post-doctoral researcher Fredric Windsor, who has studied the catchment, to review the data.

“Concentrations in brown trout in 2018 appear below most risk thresholds for human consumption,” Windsor responded. “But as muscle was sampled, presumably because monitoring aimed to understand the risk of PCBs for human consumption, the data is not necessarily that informative regarding risks to organisms.

“Many hydrophobic chemicals can accumulate to higher, harmful concentrations in other organs such as the liver, even when there are low concentrations in other tissues. And brown trout are not apex predators in these ecosystems: predators across the wide river food web, such as dippers and otters, may exhibit higher, potentially more damaging concentrations due to biomagnification.”

Campaigners are even more worried.

“The levels of PCBs that NRW reported in the Caerphilly area for trout should concern people who eat them regularly, but the Food Standards Agency for Wales is probably not aware of these data,” says GM Freeze campaigns director Peter Riley, who filed the FOI request. “Generally fatty/oily fish will contain more PCBs, especially eels. It is surprising they are not testing them.”

PCBs are heavy compounds, Cawthorne points out: where river water tests negative for PCBs, there may be toxins in the sediment or leached into local fields.

“Why aren’t the authorities testing sediments all around these sites?” he says. “They’ve been testing the water column. Time that right, and the traces wash away. When tests don’t reveal PCBs, we conclude there’s no problem. That’s the disconnect.”

If all PCB-linked landfills were designated “special sites”, he argues, regulators could identify the “appropriate persons” liable for the pollution and seek compensation to fund remediation.

Mind the gaps

The couple who farm next to Brofiscin, who reported the deformed calf, are sitting down to lunch. The presence of toxins was obvious in the seventies, pouring into local watercourses whenever it rained, the husband says.

He welcomes us to check the stream below his field and to climb the ridge that overlooks the quarry. We swerve his horses and cross two fields to the stream. The trees rooted closest to it are shorter, less leafy than more distant ones.

The watercourse is dry – it hasn’t rained for weeks. No plants grow from its bed. Tree stumps and a discarded plastic bucket are coated a garish orange, as though rusted.

Above the quarry, the scent of ramson flowers hangs in the air. The undergrowth is thick with wild garlic. You’d sell it for a fortune at a farmers’ market. Is Cawthorne tempted to pick some? He looks horrified. When The Ecologistmagazine tested the soil at Brofiscin in 2007, it recorded two dozen buried nasties.

We travel on to Maendy East. It, too, is freshly gravelled. The site forms a bowl, three sides thick with scrubby brambles. Cawthorne plunges into the undergrowth. Barely five metres in, a chemical stench overwhelms us. I insist we leave at once. Back on the gravel, Cawthorne doubles up retching.

The Environment sent questions about how legacy sites are managed and monitored for contamination risk, to NRW, to Veolia and to Rhondda Cynon Taff borough council. All sent brief written statements.

“Any decision to investigate a potential contaminated land site would be in accordance with statutory guidance, the council’s contaminated land-inspection strategy and the availability of appropriate funding, RCTBC said.

It directed questions about monitoring Maendy and its impacts to NRW.

NRW sent its policy position statement: “PCBs are a global problem but the regulation we have in place is taking effect. Records show the discharge of PCBs into the environment has reduced significantly over the years, due to tighter controls on use and disposal, remediation of some historically contaminated sites and the passage of time.”

Veolia, which owns Maendy, says it samples surface and groundwater as per its 2018 permit from NRW. “We’ve achieved encouraging results, shared with the regulator at the end of last year, showing no PCBs were discharged,” said a senior spokesman.

“Our additional controls will help manage residual contamination and minimise impact on water quality. Veolia will continue to monitor the site in line with NRW’s permit conditions and remains committed to its restoration and improvements in environmental performance.”

Clean Rivers Trust director Harvey Wood says generations of politicians, local authorities and regulators have ignored risks from dumped contaminants.

“These sites are not being monitored,” he says. “We simply fence them off to keep the public away. Managing these sites properly would cost money. Governments of all political persuasions have buried their heads in the sand.”

The Welsh government launched an urgent, nationwide coaltip-safety review after a Rhondda tip collapsed near Tylorstown in 2020. Driving rain during Storm Dennis saturated and weakened the site. Wood calls for a similar, urgent UK-wide review of climate risks linked to PCB dumps and other landfill sites.

Budget cuts have made agencies less able to monitor and model future risks from legacy chemicals, Windsor says. “Chemicals perceived to have reduced risk – whose manufacture and/or use has been banned – have been removed almost completely from routine monitoring.

“For some chemicals there remain large stores of waste. Remaining monitoring focuses on these – but at the cost of limited data on prevalence and concentration of these chemicals across the rest of the catchment.”

Put all that together and “current monitoring is unlikely to provide an accurate or complete understanding of the environmental risk from legacy chemicals”, he says. “The current state of our understanding and monitoring increases our reliance on reporting from the public – the situation for Maendy and Brofiscin.”

Sediment monitoring has its limitations. Windsor advises closer monitoring of organisms. “Sediments can be extremely heterogeneous in size and concentrations of organic matter, which makes collecting representative samples challenging, costly and/or time consuming,” he says.

“Our previous work, comparing sediment concentrations to those from organisms, found that organisms can provide space- and time-averaged concentrations of legacy chemicals and additional information on patterns in the environment… We can directly translate that data into an environmental risk estimate.”

Who pays?

Cawthorne believes remediation costs would run into the hundreds of millions, should we pin down the scale of our PCB problem. “It comes down to what we define to be contaminated,” he says. “The easiest thing is not to designate the land to be contaminated in the first place.”

In other words, what we don’t see, we don’t need to tackle. And what we don’t need to tackle, we won’t have to pay for.

But our wildlife is already paying for it. There is growing evidence of the deadly impacts of PCB contamination on nature. A 2000 University College London PhD study on concentrations of PCBs in marine sediments and dredged material described Cardiff Bay and the River Blyth as “hotspots” for concentrations of PCBs in estuarine sediments.

Author Jacqueline Reed concluded: “PCB concentrations in a third of all dredged material samples analysed since 1990 exceed current sediment-quality guidelines. Many of the most contaminated samples have been obtained from commercial dockyards in South Wales, principally Cardiff, Newport and Swansea.”

A 2003 Southampton University study found leachate discharge from Maendy had polluted the local stream for 800m, with toxic impacts on lab-raised freshwater shrimps and lice. The stream flows into River Ely.

A broader 2019 study by ZSL found the higher you go up the food chain, the higher the PCB load. Having found high concentrations of PCBs in European waters, ZSL is monitoring the long-term impacts on whales and dolphins. The UK’s last pod of orcas has produced no calves in 20 years. ZSL links the crash in birthrates to concentrations of PCBs in the orcas’ blubber.

Studies from ZSL, Chem Trust and others link falling populations of cetaceans, otters, mink, seals and polar bears to concentrations of PCB contaminants. In 2019 Water Research published a Cardiff University-led study of persistent contaminants in Welsh rivers that attributed slow recovery in native river species to a mix of urban pollutants, including legacy contaminants.

Chemicals categorized as PCBs vary in toxicity. ZSL lead author Rosie Williams calls for more join-up “to change our approach to monitoring PCBs… to get a better understanding of the risk these chemicals pose to our marine wildlife”.

The final twist to the story of Monsanto in South Wales is that its former plant still pumps legacy chemicals into the Severn Estuary. NRW permits site operator Solutia to dispose of legacy chemicals – including PCBs, trichlorobenzene and pentachlorophenol – in the Severn Estuary via a 5km waste pipe. NRW declined to discuss this.

It all adds up to growing alarm about how we monitor and manage forever chemicals accumulating in the environment. Writing in The Guardian this spring, George Monbiot slammed “the near-collapse of monitoring and enforcement” of pollutants entering our waterbodies.

In June, 30 NGOs wrote to Defra, urging it to ban production and use of more than 9,000 per- and polyfluorinated alkyl substances (PFAS) from 2025 under UK chemical regulatory compliance. Wildlife and Countryside Link chief executive Richard Benwell wants “closer monitoring as part of a wholesale reform of UK chemicals policy”.

He told The Environment: “We’re largely in the dark about the environmental and human health impacts of the soup of substances we pour into our environment. Wherever we do cast a light, we find that chemicals are pervasive, persistent and polluting. The forthcoming UK chemicals strategy should be explicitly a chemicals-reduction strategy.”

UK regulation of chemicals is not fit for purpose, WCL concludes.

We need much wider testing, much better modelling to understand and manage the extent and impacts of PCBs and other legacy pollutants. Only then can we understand the risks that these forever chemicals present as our climate changes – to public health, wildlife and livestock – and set up systems of accountability and funding fit to tackle it.

But do government, regulators and authorities have the political will to deliver?

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