January 24, 2025

expert reaction to Defra denying emergency authorisation to Cruiser SB (a neonicotinoid pesticide)

Scientists comment to the Government’s decision to not grant emergency authorisation to a neonicotinoid pesticide. 

Dr Scott Hayward, Lecturer and Leverhulme Research Fellow, University of Birmingham, said:

“Definitely an evidence based decision. Ongoing research clearly shows significant effects of neonicotinoids on several pollinators species.  Research interest, and thus data, has been dominated by pollinator projects to date, but important to recognise that this is a biodiversity concern beyond just pollinators. There will be impacts on other insects and invertebrates (especially in the soil).

“Our own work shows sub-lethal doses, as low as 9 ppb (parts per billion) can negatively affect bumble bee (Bombus terrestris) performance.  Some other bee and fly species species we’ve assessed don’t seem quite as vulnerable as B. terrestris – but we’ve only looked at relatively short (24 h) durations of exposure and very few species.

“Sugar beet is somewhat of a special case because it doesn’t produce flowers until year 2 of growth, so the concerns that neonics are transferred to the pollen and/or nectar of the plant via seed coating is less of an issue than for other crops – because it is harvested before it produces flowers. However, even seed coating leaves neonic residues in the environment. 

“Several ongoing projects are trying to model how residues persist in the environment across different habitat types and assess to risk to pollinators and other insects more generally.

“Less data on what impact alternative pesticides might have, but simple fact is that pesticides targeting fundamental biological functions in pest species will likely have the same (sometimes greater) effects in non-target species.”

Prof Dave Goulson, Professor of Biology at the University of Sussex, said:

“For the last 4 years, our government ignored the recommendations of the Health and Safety Executive and the Expert Committee on Pesticides, both of which were of the opinion that this derogation request should not be granted. It is pleasing to see that our new government have followed scientific advice and refused the request. There is overwhelming evidence that neonicotinoids harm bees and other wildlife, and contaminate soils, waterways and wildflowers. There is no safe way to use them.

“Farmers across Europe have been growing sugar beet without use of neonicotinoids, so this should not be an insurmountable problem.”

Prof Toby Bruce, Professor of Insect Chemical Ecology at Keele University, said:

“What are farmers supposed to do to protect their crops? Without insecticides sugar beet growers face up to 50% crop losses. If the government plans to ban pesticides (neonicotinoids in this case), then it should also plan to fund research into development of alternative approaches. The situation was previously considered an emergency because farmers are left with no control measures and have no way of protecting their crops from insect pests and the serious crop diseases that they transmit”.

Declared interests

Toby Bruce: “I don’t have any interests to declare.”

No others received.