Grace Stickland said losing the beach had broken up a community

For more than six years, asbestos has been washing up with the tide, turning one of Plymouth's handful of swimming spots into the centre of a growing environmental mystery.

Mount Batten Beach has been fenced off since the summer, and access restricted to two other areas on the peninsula.

It comes after tests in April and July found asbestos fibres in sand samples at levels that could pose a risk to health if inhaled, Plymouth City Council said.

Inhaling the fibres can increase the risk of serious diseases - including lung cancer - decades after exposure.

The first discovery came in 2019 when 500kg (1,100lb) of material containing the toxic substance was removed from the shoreline, which sits on Plymouth Sound in one of the South West's most popular holiday destinations.

In total, more than 1.5 tonnes of material containing asbestos, external, including both white and the more dangerous blue varieties, has been cleared from the beach and nearby sites.

Residents and experts believe the material may be coming from roofing and construction waste linked to the former RAF Mount Batten base, where coastal erosion is thought to be exposing the buried material.

The closure has left swimmers, business owners and residents wondering when, or even if, the beach will reopen, and how it looks against the backdrop of Plymouth Sound being named the UK's first National Marine Park., external

City councillor Grace Stickland, who has been bathing at Mount Batten for several years, said dozens of people regularly gathered for swims throughout the year, with festive dips attracting as many as 80 participants.

"It was a really popular little beach and everybody loved it," she said.

"All the swimmers feel as though they've been evicted from their homes."

Stickland said older swimmers and people with mobility issues particularly valued Mount Batten because of its accessibility, adding that the closure was "breaking up" a community that had grown around the beach.

The National Marine Park in Plymouth Sound has faced a number of challenges in the past, including hundreds of old tyres being discovered on the seabed and sewage spills.

Yet the asbestos contamination problem has proved difficult to solve.

When asbestos was first discovered in 2019, the council temporarily closed the beach and expected the amount of material washing ashore to decrease over time but that has not been the case.

"Our beach collections have shown that the amount of material washing up on the beach hasn't shown any real decline," a council spokesperson said.

Earlier testing suggested the risk was low. Warning signs were installed and visitors were advised to avoid parts of the beach where asbestos fragments had been found.

But council officials described the latest results as a "new and worrying development".

Swimmers at Mount Batten before the beach was closed

Although two rounds of testing have found no evidence of airborne asbestos on the beach, the discovery of fibres in the sand was enough to trigger the closure.

Professor Steve Maddern, Plymouth's director of public health, said shutting the beach had been a last resort.

"We understand the disappointment this will cause but the latest sand samples are concerning and we must prioritise the safety of the public," he said in July.

While the beach remains closed, attention has turned to the question: Where is the asbestos coming from?

Residents have long suspected the source could be the former RAF Mount Batten site, which occupied the peninsula for much of the 20th Century before closing in 1992.

During its heyday it was one of Britain's most important flying boat bases, with Sunderland aircraft carrying out anti-submarine patrols and sea rescue missions during World War Two.

Today little remains beyond memorials and historic seaplane hangars.

Mallory Haas believes buried asbestos from the former RAF base is the cause of the contamination

Maritime archaeologist Mallory Haas, director of the Ships Project CIC in Plymouth, said she believed asbestos-containing roofing materials from the RAF base had been buried and were now being exposed through coastal erosion.

"If you look at what's on the beach, and if you also look at the deposits behind the staircases when you walk down to the beach, you can see it eroding out of the land there," she said.

She added: "It's Britain's Ocean City, the UK's first National Marine Park and it's an MPA [Marine Protected Area].

"It should be some of the most protected waters around."

The properties of asbestos made it an ideal material for use in a number of products, including insulation material for buildings, boilers and pipes; car brakes and floor tiles, insulating board to protect buildings and ships against fire; asbestos cement for roofing sheets and pipes.

Due to the risks to health following inhalation exposure to asbestos the importation of blue and brown asbestos has been banned in the UK since 1985.

This ban was extended to include white asbestos in 1999.

Asbestosis is a rare but serious lung condition that affects people exposed to asbestos. It cannot be cured but treatment may improve the symptoms.

It can take 20 to 30 years after being exposed to asbestos before symptoms appear.

The advice is to visit a GP if you have symptoms of asbestosis and think you have been exposed to asbestos.

Plymouth City Council said re-opening the beach was a high priority

Local MP Rebecca Smith has been pressing the council for answers; arguing the closure is having a significant impact on sea swimmers, watersports users, businesses and the wider community.

More than 140 people attended a public meeting about the issue, while a petition has been handed to Parliament calling for urgent action to reopen the beach.

The Conservative MP for South West Devon questioned why the problem had still not been resolved more than six years after asbestos was first discovered.

"You can't be the National Marine Park on one side of the peninsula and have a closed beach on the other side of the peninsula," she said.

"I will find it incredibly difficult to stand up in Parliament and talk about the National Marine Park if that beach remains closed."

Smith said the city council had a strong record of securing external funding for major projects and argued it should use those same skills to find the resources needed to resolve the beach closure.

"There's a will, there's a way," she said. "They need to be using that track record and that skill set to get whatever it takes to sort this beach out."

Nearby businesses are beginning to feel the strain as well.

The Bridge restaurant closed in September, citing the beach closure as a significant factor affecting trade.

Giant hangars and a slipway are all that remains of the RAF base

A council spokesperson said re-opening the beach was a "high priority" but a "complex task" due to the type and location of the contamination, the potential risks to public health and the need to definitively identify the source of the asbestos.

Further tests in other waterfront locations have been taking place to check whether the contamination is confined to the Mount Batten area.

A contractor, which would identify the source of the contamination and provide solutions to re-open the beach, has yet to be appointed.

"This critical work needs to be robust and comprehensive, but our aim is for it to be carried out as rapidly as possible as we fully understand – and share – the frustrations of those who want the beach to re-open as soon as possible," the spokesperson said.

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Crumbling cliffs reveal buried historical rubbish. Video, 00:01:39Crumbling cliffs reveal buried historical rubbish