Our work on neonicotinoids (neonics)

PAN UK was one of the first organisations to raise the alarm about the impact of neonicotinoids on bees and pollinators. In 2012, PAN UK published a ground-breaking series of briefings on the impact that pesticides, particularly neonicotinoids were having on bees. These briefings formed the basis of a submission to an inquiry held by the UK Environmental Audit Committee into the impacts of neonicotinoids on pollinators.

Our work, together with other organisations in the British Bee Coalition, helped raise awareness of the issue with the public and key decision makers in the UK and the EU. Working with others we motivated millions of citizens across the EU to sign petitions and lobby their politicians to ban the use of neonicotinoids. At the same time we disseminated key scientific studies that clearly showed the harm that pesticides do to bees and pollinators.

In April 2013, the first signs of success came when the EU imposed a temporary ban on three neonicotinoids while they reviewed more scientific studies and field studies on the impacts of these pesticides. Finally, as a result of ongoing pressure from PAN UK and our colleagues as well as the public in the EU and the constant stream of scientific studies, an almost complete ban on the three most toxic neonicotinoids was brought into force in April 2018.

The fight is not yet over to protect our bees and pollinators, but a significant battle has been won.

Between 2000 and 2016 the weight of neonicotinoids applied to all crops in the UK increased from 26,404kg to 87,704kg – an increase of 232%.

What are neonicotinoids?

Neonicotinoids (neonics) are the most widely used insecticides globally. They are used on more than 140 crop varieties to control a variety of pests especially sap-feeding insects, such as aphids and root-feeding grubs. They are also common in veterinary applications such as tick control and flea collars for pets.

They are a relatively new type of insecticide. The first, imidacloprid, was launched by Bayer Cropscience in 1991. Since then a further six compounds have been put on the global market. By 2008, neonicotinoids had taken a 24% share of the total insecticide market of €6.330 billion.

Neonics are systemic pesticides. Unlike contact pesticides, which remain on the surface of the treated foliage, systemic pesticides are taken up by the plant and transported to all its tissues (leaves, flowers, roots and stems, as well as pollen and nectar). Products containing neonics can be applied at the root (as seed coating or soil drench) or sprayed onto crop foliage. The insecticide toxin remains active in the plant for many weeks, protecting the crop from pests season-long.

Between 2000 and 2016, the weight of neonicotinoids applied to all crops in the UK increased from 26,404kg to 87,704kg – an increase of 232%.

Are neonics banned in UK?

Neonicotinoids, especially seed treatments of imidacloprid, clothianidin and thiamethoxam on arable crops, were shown to be causing harm to bees and other important insects. As a result, these three were banned for use by the European Union on 27th April 2018, but remain in use in many other places in the world.

Thiacloprid was withdrawn from use in 2020 due to its potential to harm human health and its ability to remain in ground water. Thiacloprid is also toxic to bees and other pollinator species.

In the UK, one neonicotinoid insecticide is authorised for use: acetamiprid. It is used as:

seed treatments for cereals
soil treatment for pot plants in the ornamental sector
foliar sprays on apples, pears and a range of glasshouse crops
insect sprays for plants in homes and gardens (these include BugClear Ultra and RoseClear Ultra)

Ongoing risk to bees and other pollinators

Despite the ban on neonicotinoids, bees and pollinators are still at risk from the harms they cause. The use of emergency derogations from agribusiness claiming that it’s impossible to grow crops without using the banned insecticides is undermining the ban. The problem is particularly prevalent in certain EU Member States such as Hungary and Poland where derogations for use on oil seed rape and sugar beet have been granted by their governments. In the UK, applications for derogations have been submitted and for the most part denied. But there is ongoing pressure from the UK sugar beet industry to allow the use of neonicotinoids in certain circumstances.

UPDATE

In January 2021, the UK Government bowed to pressure from the sugar industry and granted an emergency derogation allowing sugar beet farmers to use seeds treated with the neonicotinoid thiamethoxam. In response, PAN UK mobilised a broad range of organisations to urge the UK Government to reverse the decision and instead invest in supporting farmers to adopt non-chemical alternatives.

However, due to pest thresholds not being met the derogation was not acted on in 2021 and thiamethoxam was not used by sugar beet growers that season.
In March 2022, another emergency derogation request submitted by the sugar industry was granted by then Defra minister George Eustice. The neonicotinoid was applied as a seed treatment to protect the sugar beet crop from the Yellow Virus that is carried by aphids.

PAN UK’s response to this emergency authorisation can be read here.

Further reading: our blog post ‘Bees, beets and obesity‘ outlines the links between neonicotinoids and the sugar industry.

Neonicotinoids are an insecticide that pose a risk to bees and other pollinators

How do neonics work?

Neonics affect the central nervous system of insects. They bind to receptors of the enzyme nicotinic acetylcholine, causing excitation of the nerves, leading to eventual paralysis and death. This specific neural pathway is more abundant in insects than warm-blooded animals and are therefore selectively more toxic to insects than mammals.

Bees have a particular genetic vulnerability to neonics because they have more of these receptors than other insects, as well as more learning and memory genes for their highly evolved system of social communication and organisation. Unlike many insect pest species which are able to detoxify harmful chemicals, bees possess fewer genes for detoxification.

While the older organophosphate and carbamate insecticides tend to degrade quite rapidly in the environment, neonics are more persistent. Imidacloprid can last for months or years in soil and may leach into groundwater under some conditions.

Neonics were originally welcomed as much safer for humans, livestock and birds than other insecticides. Seed treatments were seen as a more effective method of targeting pests than spraying crop foliage, and more environmentally-friendly because they can reduce the number of spray applications needed in-field. However, over time, it has become clear that they pose different and poorly understood risks to bees and other non-target invertebrates precisely because of the properties that have made them so useful to farmers: their systemic action; their persistence in crops and soil; and their potency at low concentrations. Added to this, their widespread use in many cropping systems and their unplanned presence in pollen and nectar builds up a worrying picture of low level but continued exposure for pollinators, which our regulatory risk assessment schemes are only just starting to address.

Why are Neonics so Bad for Bees?

Acutely Toxic by Direct Contact

Like many other broad-spectrum insecticides, neonicotinoids are acutely toxic to bees and other pollinator species by direct contact or by mouth. To prevent accidental contact exposure, products containing neonics carry warnings on the label and instructions to avoid spraying on crops in flower or at times when bees are foraging in fields or close by. Making sure that all farmers comply with these instructions remains a challenge.

Sublethal Effects in Pollen & Nectar

Neonics may be present in pollen and nectar at levels sufficient to impair pollinator health, including disruption to foraging behaviour, homing ability, communication and larval development. Neonic levels in pollen can cause chronic harm to the bee brood. Several studies show that exposure to insecticides at low doses can negatively affect the immune system of bees, making them more susceptible to the impact of parasite and disease infections. A clear increase in growth of Nosema fungal disease was reported in bees reared in colonies exposed to very low doses of imidacloprid, at levels below those considered harmful to bees.

Mechanical Problems with Treated Seeds

There have been numerous serious acute bee poisoning incidents due to mechanical problems with the seed treatment process and field sowing of neonicotinoids. In southwest Germany in 2008, millions of bees died following sowing of maize seed treated with clothianidin. The seed companies involved had failed to apply the sticking agent properly during seed treatment, causing clothianidin-laden dust to be released from the drilling machines. In parts of the US Mid-West in 2010, significant bee kills were reported during spring sowing of maize. Clothianidin and thiamethoxam were found responsible, via the talc used to allow treated seed to flow smoothly through the air-assisted planter equipment. Bees were killed through exposure to the contaminated talc exhaust behind the tractor.

Toxic Breakdown

Neonic breakdown products can be much more toxic than the original pesticides, posing a risk to bee larvae which may be exposed to the longer-lasting breakdown products inside the hive.

Exposure Via Other Routes

Neonics can also remain active in the soil for months, either being taken up unintentionally by crops in the following season or being transported in soil dust to contaminate flowering weeds or contact insects directly. Research also shows that very high concentrations of insecticides can be excreted by treated seedlings in ‘guttation’ droplets on young leaves, posing a risk to bees and other insects which sometimes collect these droplets as drinking water for the hive.

Working to protect human health and the environment from pesticides