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A Chemical in the Works? The Mystery of the Marine Deaths on Teesside

Graham Williamson reports on a spate of unexplained sea life deaths on the north-east coast – and a new freeport being built on the site of an iconic steelworks nearby

Rishi Sunak with Tees Valley Mayor Ben Houchen at the Teesside Freeport site. Photo: Owen Humphreys/PA/Alamy

A Chemical in the Works? The Mystery of the Marine Deaths on Teesside

Graham Williamson reports on a spate of unexplained sea life deaths on the north-east coast – and a new freeport being built on the site of an iconic steelworks nearby

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For more than a year now, the north-east coast has been suffering mass deaths of marine life. It started last October, with crustaceans particularly badly affected, and local lobster and crab fishers reporting a 95% decline in their catch. 

The development caused alarm – Yorkshire and the Humber is the second-largest sector of the UK’s fishing economy. Compounding the fear, no one knew why it was happening. Mass ‘die-offs’ of marine life are not unheard of, with March 2018 seeing similar incidents take place across the country following a cold snap. These deaths, however, were happening solely on Teesside, suggesting something very nasty in the North Sea.

The Department for Environment, Food and Rural Affairs’ initial investigation concluded that a toxic algal bloom was responsible. The algae in question, however, disappeared last autumn after a seasonal change in sea temperature. Yet incidents suggestive of seawater poisoning kept happening.

By January this year, dog owners were being warned to stay away from the coast when hundreds of pets fell ill after being walked on the beach. The most recent incident occurred on 21 September, with beaches covered in dead shellfish. 

Following a meeting of Parliament’s Environment, Food and Rural Affairs Committee this week, DEFRA’s scientific advisors made clear that they no longer believe that algal bloom is the cause of these devastating mass deaths. The priority, they said, is to immediately suspend dredging along the River Tees until further tests can be carried out.

This brings DEFRA in line with the beliefs of most locals, whose emails to the committee were summarised by Liverpool Labour MP Ian Lavery as arguing that “the environmental impact is a secondary consideration” to the rolling-out of the Government’s ‘levelling up’ project in the form of a freeport at Teesworks on Teesside that is currently the biggest building site in Europe.

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I’ve lived on Teesside all my life and, in all that time, the Redcar skyline has been dominated by Teesside Steelworks. Once a central part of the region’s economy, it was mothballed in 2009 with the loss of 1,700 jobs. Hopes were raised when the plant was bought by SSI in 2011, but the firm’s UK branch entered into liquidation in October 2015, ending the history of steel-making on Teesside.

At that time, I was working in the NHS and vividly remember the increase in deaths of despair; men in their fifties unable to cope with the loss of the industry they spent their lives in. Steel can be a very emotional matter in a place like Teesside. Last March, the Teesside freeport was announced. And when demolition began at the former steelworks this summer, people welcomed it.

Stakes in the Teesport site’s development company, Teesworks Ltd, were initially split 50/50 between the South Tees Development Corporation and a consortium of investors, including major donors to the Conservative Tees Valley Mayor Ben Houchen and the Conservative MP for Middlesbrough South and East Cleveland, Simon Clarke.

As of this month, that consortium has increased its share to 90%. This was covered in a recent Private Eye investigative special focused on the Teesside freeport. But worse was to come.

In the search for answers about the mass die-offs, locals realised each event was preceded by the river being dredged.

Scott Hunter, of the independent local news site Tees Valley Monitor, noticed that, during a 10-day period ending on 4 October 2021, the harbour authority PD Ports dredged 66% of the annual amount it was permitted to move by the Marine Management Organisation. Later that month, dead animals began washing up on Teesside’s beaches.

There is no evidence to suggest that this increased dredging activity was connected to the freeport, nor was it outside PD Ports’ license. It was an unusually intensive operation, though, and if it could be linked to the mass marine deaths it would raise serious questions for the freeport, the construction of which requires even heavier dredging. 

In response, Mayor Houchen accused critics of the initial DEFRA report of believing that the deaths are caused by “Agent Orange, apparently, from secret factories in the Second World War… completely conspiratorial ideas”. But there was already a more plausible chemical suspect in the frame, thanks to the work of Dr Gary Caldwell at Newcastle University.

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According to Dr Caldwell, the likely culprit is pyridine – an industrial solvent which he proved is lethal to crabs. On the BBC’s We Are England programme, he explained its terrifying potency: “A single drop of pyridine in a litre of seawater – that is enough to kill half the [crustacean] population in three days.” 

Journalist Scott Hunter backs the theory. “The most obvious source of pyridine is Teesworks, as it is a by-product of coking and there have been at least three coke batteries on that site,” he told me. “Go after Teesworks, however, and that interferes with plans for the freeport” – something few public figures on Teesside are willing to do.

When the National Audit Office gave Teesworks the all-clear in August this year, the Northern Echo‘s business and commercial editor Mike Hughes dashed off a quickly-deleted tweet congratulating Mayor Houchen and mocking “the doubters”. On the same day, he wrote an article quoting an anonymous civil servant as saying “other sites across the country of a comparable nature have not progressed anywhere near as quickly as Teesworks”.

Driven by Conservative politicians looking to make their mark in an area that rarely votes for them, and a Chancellor – now Prime Minister – with an ideological propensity for freeports, the risks surrounding a highly dangerous chemical that’s been buried in the mud of the Tees for decades have been ignored.

Hopefully, the sea change at DEFRA on the cause of these marine deaths will allow for serious investigation, without politics obstructing a matter that – if mishandled – could spell the end for another of the north-east’s industries.


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