Welsh communities grapple with toxic legacy of metal mining

“We had no idea before we moved here that we were living downstream from an old lead mine,” recalled Elizabeth, speaking from her home in west Wales.

“We have always eaten everything we’ve grown here. Not one official has ever come and told us not to,” she said. “Surely someone would be testing the soil if they know it could be a risk to our health?”

Elizabeth, not her real name, is just one of as many as half a million people in the UK estimated to be living on land contaminated by historic metal mining from the 19th and 20th centuries.

In Wales alone, more than 1,300 abandoned sites leak metal pollutants into the environment each year, including lead, zinc and cadmium.

These metals are dispersed downstream, where they accumulate invisibly in land and water used for agricultural or home food production.

Just 129 old mines release up to 500 tonnes of harmful metals into natural systems annually, according to government estimates obtained by the Financial Times.

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Since a wave of mine closures in the early 1900s they have been largely forgotten by successive governments, as they lie in sparsely populated and rural areas. The cost of remediating the sites can be high.

Responsibility for remediating former mine sites belongs to environmental regulators Natural Resources Wales and the Environment Agency. However, it is not clear whose duty it is to inform the public of the possible risks to homegrown food.

Officials told the FT there was an absence of regulatory standards when it came to the impact of former mines on human health.

While environmental agencies are responsible for monitoring former dig sites, under-resourced and overstretched local authorities have a duty to identify contaminated land and test produce to ensure it is safe, according to central government.

Of all the metal pollutants discharged by mine sites, lead is especially dangerous to humans, with the World Health Organization warning there is no level of exposure known to be without harmful effects.

In adults, it can increase the risk of heart attacks, miscarriage, preterm births, depression and chronic kidney disease. Children are the most vulnerable to exposure and at risk of life-long reductions in cognitive function as well as behavioural problems. 

“We used to let our son go up on the spoil tips with his bike,” Elizabeth, who has lived with her husband in a small village downstream from an old lead mine for more than two decades, recalled with horror.

“There was no one telling us this could be dangerous for him, I wish I had known better,” she added.

In 2018, Natural Resources Wales gave a grant to Andrea Sartorius, a University of Nottingham PhD student, to investigate whether two abandoned lead mines had contributed to a spate of animals deaths on two farms in rural west Wales.

As well as dead animals, Sartorius studied chicken eggs, which she said were sold locally and eaten by the farmers themselves.

Her thesis concluded the eggs contained concentrations of lead that could “pose health risks” to humans. A child under eight years of age regularly eating one to two of them “could become cognitively impaired”.

Small-scale studies of vegetables grown on the farms indicated they too contained “elevated, and potentially toxic, concentrations” of lead.

Farmers had told Sartorius stories of horses and ducks dying. She examined their livers and kidneys and discovered their levels of lead were above accepted toxicity thresholds, leading her to suspect they had died of poisoning.

The two small, private farms she studied were located 0.6km and 4km downstream from two abandoned lead mines in west Wales.

Sartorius found both properties displayed “substantially elevated trace metal concentrations in the water, sediments, and soils”.

In some instances these levels were “even higher than those detected at the mine site”, she explained to the FT, adding that this may be due to pollution accumulating over time.

One of the farms kept its chickens beside a driveway built with mine spoil. The birds contained lead concentrations well above the threshold for “acute toxicity”, she found.

This newspaper has spoken to people living in west Wales who said it was common for locals to use the spoil as gravel for their driveways because weeds and plants do not grow in it.

Due to the sensitivities surrounding these issues, the residents interviewed by the FT agreed to speak on condition of anonymity. 

Sartorius’s findings prompted the Welsh government to convene two meetings last year with officials from across the UK, including both the Food Standards Agency and Health Security Agency.

“Everyone that I met with was aware that they lived near an abandoned mine site,” she said. “But they were not aware of the potential risks to their health.

“I spoke to people who had moved to rural Wales to become self-sustainable, only to find out that it’s unsafe to do so due to the high levels of lead in their land,” she added. “It was really quite devastating.”

The presence of lead in domestic chicken eggs was of particular concern, she added, “as chickens rarely exhibit symptoms of lead toxicity, and lead-contaminated eggs appear normal”.

As there is no maximum limit for lead concentrations in eggs in the UK, Sartorius used European Food Safety Authority’s daily lead consumption thresholds in her study. The samples she collected were also measured against supermarket eggs in England.

Government officials confirmed that no information had been given to the people living in these areas on the potential risks of using spoil, growing vegetables and keeping domestic chickens.

The FT contacted several local authorities in west Wales. Only Ceredigion responded, saying the council took “a collaborative approach” when providing advice to the public.

It added that it would “need to receive guidance from government agencies, prior to issuing advice on the potential lead contamination of foodstuffs in specified locations”.

“There is currently a lack of regulatory standards relating to this issue,” it added. They noted that the Nottingham university study “recommends more research on the matter, which we fully support”.

Professor Lisa Yon, who oversaw Sartorius’ research, said academics at Nottingham university “suspect the issues detected” on the two sites “may well reflect the situation” in disused mines across the UK.

She added that the risk to human health “urgently requires further investigation”.

The extent to which the public has been exposed to lead is unclear. Unlike countries including the US and Canada, the UK does not conduct national biomonitoring programmes that monitor exposures to specific harmful substances.

The US National Health and Nutrition Examination Survey and Canadian Health Measures Survey are ongoing and can be used to monitor exposures to environmental chemicals, such as lead, PFAS and pesticides.

Professor Bruce Lanphear, a health sciences expert at Simon Fraser University in Vancouver, who has researched lead exposure for decades, said: “Given how toxic chemicals adversely affects human health, I find it puzzling that a scientifically advanced country like the UK lacks a nationally representative biomonitoring programme.”

The Welsh government has been aware of the possible human health risks associated with these mines for decades. In 2002, NRW published a report that acknowledged metal mine sites presented significant sources of land, water and air pollution. 

The report referenced research carried out by academics in 1978, which found “elevated lead concentrations” in the blood of adults and children in a village situated adjacent to a complex of metal mine spoil tips. 

“No one told us before we moved here,” said one homeowner living in another village downstream from an abandoned lead mine in west Wales.

“It’s certainly something to bring to people’s attention. There are livelihoods to be considered but there’s also people’s health.”

A Welsh government spokesperson said: “We continue to work with stakeholder organisations to ascertain the nature and extent of metal mine pollution in Wales in order to identify suitable methods to manage any pollution impacts associated with this legacy issue.”