The Government has decided to allow the emergency use of the neonicotinoid thiamethoxam on sugar beet in England in 2021, despite objections from conservationists. The decision, in response to pressure from England’s farmers, will permit the treatment of sugar beet seed to combat beet yellows virus, which is spread by multiple species of aphids.
Neonicotinoids are broad spectrum neurotoxic insecticides; they are designed to kill all insects in all stages of their lives by attacking their central nervous systems. Neonicotinoids are also systemic, they dissolve in water and are absorbed by plants, making the plant itself toxic. All parts of a plant grown from neonicotinoid coated seed, its roots, leaves, flowers and pollen, can be toxic to insects for years after the initial treatment.
Pollinators:  honey bee;  marmalade hover fly;
The use of these systemic insecticides is believed to have contributed to the widespread loss of pollinating insects in the UK, particularly our honey bees. Insect pollinators are vital for global ecosystems and for food security: 75% of our crop species, 35% of global crop production, and up to 88% of flowering plant species are all dependent on insect pollinators.
The chemistry of neonicotinoids is stable and persists in the ground water. Research has shown that, applied as seed treatment, only 5% of the toxin is absorbed by the plant and the other 95% remains in the soil. Because they are water soluble, the insecticides are taken up by the annual wildflowers that grow after a treated crop has been harvested, or wash down into our waterways where minute amounts can kill the aquatic nymphs of water flies, seriously damaging freshwater food chains.
Water fly:  dragonfly;  damselfly
The agricultural use of thiamethoxam was totally banned in the EU in 2013 but, of course, we are no longer a part of the EU and those protections no longer apply in the UK. There are also neonicotinoids still commonly available in veterinary applications such as tick control and flea treatments for pets.
It is time to permanently ban all neonicotinoids in the UK. We can no longer pretend that they can be used safely; we know how dangerous they are. We have to make room for our damaged and failing invertebrate populations to recover while recovery is still possible.