The EU General Court has upheld the region’s partial ban on three neonicotinoid pesticides that have been blamed for killing off bees, dismissing cases brought by agrochemical manufacturers Bayer and Syngenta.

On 17 May, the court confirmed the validity of the partial ban on clothianidin, thamethoxam and imidacloprid insecticides, introduced in 2013 for crops including rapeseed, maize, wheat, barley, oats and some spring cereals.

The court said the EU’s “precautionary principle” meant that the EU could take measures if there was scientific uncertainty about risks to human health or the environment, and did not have to wait until it was clear harm had been caused, Reuters reported.

According to studies, neonicotinoids could disorient bees and prevent them from finding their way back to their home hives, while also weakening their resistance to disease, Business Live said.

In recent years, there had been growing concerns over the health of bees – which pollinate 90% of the world’s major crops – with pesticides blamed for colony collapse disorder, along with mites, virus and fungus.

In April, the EU banned all outdoor use of clothianidin, thamethoxam and imidacloprid, limiting their use to crops in greenhouses.

Reuters said imidacloprid was developed by Bayer CropScience, clothianidin developed by Takeda Chemical Industries and Bayer CropScience and Syngenta was behind thiamethoxam.

Syngenta called the EU’s ruling “disappointing and unfortunate”, accusing the court of enacting the ban outside of legally approved regulation.

“The handling of this specific case reflects our more general concern at the approach the European Commission is taking to regulating technology in agriculture,” Syngenta said in a statement.

“This has negatively affected all interested parties and, above all, has damaged consumer trust.”