Bee-killing neonicotinoid pesticides were found to be present in 85% of rivers tested in England in 2023 and 2024 by the Environment Agency, according to new analysis from the Rivers Trust and Wildlife and Countryside Link which was published today (December 2024).
23 out of the 27 surface water areas were found to have tested positive for the presence of one or more neonicotinoids, which is a 6% increase in the corresponding figures for the period 2020-2022, indicating a notable rise in pesticide pollution in English waterways.
Neonicotinoids (also know as neonics) are among the most widely-used insecticides globally and are detrimental to bees and other pollinator species.
Unlike contact pesticides which remain on the surface area of treated foliage, neonics, which are a form of systemic pesticides, are absorbed by and transferred throughout the plant, remaining active and thus, toxic for weeks after.
According to Pesticide Action Network UK, the use of neonicotinoids has multiplied exponentially, increasing from a weight of 26,404kg applied in 2000 to 87,704kg applied in 2016, which is an increase of 232%.
Pesticides
As a result of the gravity of the risk posed to pollinators like the bee, the usage of three popular types of insecticides- imidacloprid, clothianidin and thiamethoxam – were banned within the European Union in 2018, but all three have remained in use in the UK.
According to the report, Clothianidin and Imidacloprid were found to be the most prevalent of insecticides, with evidence of both found in 64% (29 of the 45) of rivers tested between 2020 and 2024.
Clothianidin is a neonicotinoid in its own right but it is also a derivative of thiamethoxam, the prohibited pesticide commonly used to reduce the incidence of yellows virus on sugar beet crops.
Thiamethoxam is particularly lethal for bees, with one teaspoonful capable of killing 1.25 billion bees, according to the report.
Following lobbying from the company, British Sugar, the government has granted the ’emergency autorisation’ of thiamethoxam for the last four years, despite contrary advice from both the Health and Safety Executive and the Expert Committee on Pesticides as well as widescale public opposition.
It remains to be seen whether the new labour government will extend the emergency authorisation for the fifth year in a row.
CEO of Wildlife and Countryside Link, Richard Benwell, said: “The extensive presence of potent pesticides in rivers is another smoking gun in the hands of intensive agriculture and the decline of nature.
“The Labour Party has pledged to end emergency authorisations of the use of banned neonicotinoid pesticides and to halve the risk of pesticide pollution by 2030.
“The sugar industry has again applied for emergency authorisation to use Cruiser SB coated sugar beet seeds and if approved this would make the 5th year in a row of ‘emergency’ use of neonicotinoids.
“The government must surely deny the request and redouble farming reforms to offer generous support for farmers who cut right down on chemical use.”
While imidacloprid is also banned for use on crops in the UK, it is still used in tick and flea treatments, which is the likely main source of imidacloprid pollution in rivers.
Areas where sugar beet farming and processing is concentrated, particularly the east midlands and east of England, saw some of the highest detection rates of neonics in the river samples tested.
The largest numbers of neonics were found at single sites on the River Waveney and River Wensum in the east midlands, where all five of the neonics analysed for were detected.
Other sites that had high numbers of neonics detected included:
- East of England- River Nene, River Ouse and River Ivel;
- West-midlands- River Lugg, River Tame and River Teme
- East-midlands- Sincil Dyke and the River Dove;
- Yorks and Humber- River Ouse and Ancholm;
- South-east- River Test;
- South-west- River Chelt;
- North-west- the River Douglas.
27 river sites across the whole of England were tested for neonics in 2023 and 2024, which is over a third less (37%) than the 43 sites tested in 2020-2022, which nature charities believe is indicative of the decline in river monitoring executed by the regulator.
Director of Policy and Science at the Rivers Trust, Dr. Rob Collins, added:
“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.”
