Bee-killing pesticides have been found in 85% of tested rivers in England, an analysis of Government figures has found.

Green groups looked at Environment Agency data on neonicotinoid pesticides in river sites tested between 2023 to 2024.

They also found that the proportion of rivers affected appears to have increased from 79% during the testing period of 2020 to 2022.

Neonicotinoids destroy bees’ nervous systems and are banned in Europe, but have been authorised for use every year in the UK since 2021.

Research has found that aquatic insects and mayflies are also vulnerable to neonicotinoids, with potential follow-on implications for fish and bird populations in the wider food chain.

The Government is currently thinking of allowing the use of a neonicotinoid on sugar beet crops despite promising to ban it when campaigning for the general election, the Guardian reported.

The Rivers Trust and Wildlife and Countryside Link, which carried out the analysis, found that areas where sugar beet farming and processing is concentrated, particularly the East Midlands and East of England, had some of the highest detection rates of neonicotinoids in tested river samples.

Many of the rivers in these regions also had the highest number of detected pesticides.

The South West and South East, meanwhile, had the highest overall neonic detection rate, in 54% and 41% of samples respectively, the analysis showed.

The largest numbers were found at single sites on the River Waveney and River Wensum in the East Midlands, where all five of the neonicotinoids analysed for were detected.

Other sites that had high numbers detected included the River Nene in the East of England, River Lugg, the River Tame in the West Midlands, Sincil Dyke in the East Midlands, River Ouse in Yorkshire, River Test in the South East, River Chelt in the South West and the River Douglas in the North West.

But the campaigners also noted that only 27 river sites across the whole of England were tested for the pesticides in 2023-24, down from 43 sites in 2020-2022.

This marked a fall of more than a third (37%) in the number of sites tested.

Summer weather July 31st 2024
Combine harvesters gather in crops in Kent (Gareth Fuller/PA)

They warned that this is an indicative sign of the worsening resources of the Environment Agency and the resulting decline in river monitoring by the regulator.

During this summer’s election campaign, Sir Keir Starmer said: “The new government will ban neonicotinoid pesticides imidacloprid, clothianidin and thiamethoxam due to their impact on bees.”

But British Sugar and the National Farmers’ Union (NFU) applied to be allowed to use neonicotinoid Cruiser SB on sugar beet, which tackles a plant disease known as virus yellows.

If approved, it will mark the fifth year in a row of emergency use of neonicotinoids.

Richard Benwell, WCL chief executive, said: “The Government must surely deny the request and redouble farming reforms to offer generous support for farmers who cut right down on chemical use.”

“The extensive presence of potent pesticides in rivers is another smoking gun in the hands of intensive agriculture and the decline of nature,” he said.

Barnaby Coupe, senior land use policy manager at the Wildlife Trusts, said: “The UK Government’s pledge to end the emergency use of these bee-killing pesticides must be signed into law.

“Pollinating insects like bees are the foundation of a healthy ecosystem and essential for pollinating crops.

“These chemicals are banned because they are extremely harmful for soils, water, wildlife and human health. The evidence is clear that the environmental risks from neonicotinoids are far too great – there is no place in modern society for them to be used.”

Dr Rob Collins, director of policy and science at the Rivers Trust, said: “The widespread presence of neonicotinoid pesticides in rivers raises alarm bells for the health of our freshwater ecosystems and contributes to the huge cocktail of chemicals afflicting rivers, derived from agriculture, industry, transport and our homes and businesses.

“We need to see greater resources made available to monitor chemicals in the environment and systemic change that delivers a much more sustainable approach to their use, right across society.”

A Defra spokesperson said: “We are committed to tackling all sources of pollution to clean up our rivers, lakes and seas.

“This government has been clear that we will change existing policies to ban the use of neonicotinoid pesticides that threaten bees and other vital pollinators.”