More than 50 campaign groups have called on the Dutch cabinet to oppose plans by the European Commission to relax rules on the use of pesticides, warning that the proposals pose a serious threat to biodiversity and public health.

The organisations, including Natuurmonumenten, the Butterfly Foundation and the Parkinson Association, were reacting to a commission announcement this week about simplifying regulations for farmers and growers. The commission says the changes would save billions of euros for agricultural businesses and governments.

Critics argue that the plans would weaken existing safeguards. Under the proposals, some pesticides could be approved more quickly and for an indefinite period. Chemicals that have been shown to be toxic would also be allowed to remain in use for longer, with the phase-out period extended from 18 months to three years.

“We were hoping for progress, but what we are seeing now is a deterioration,” said Petra van de Putten-Clauwens, who has Parkinson’s disease. On Thursday morning she handed a petition to MPs responsible for agriculture, together with other patients.

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While it is not yet possible to prove a direct link between pesticide exposure and Parkinson’s disease in individual cases, evidence of a connection is mounting, the organisations said.

Nijmegen-based neurologist Bas Bloem, who also signed the letter, has previously warned that Parkinson’s could become a global pandemic if pesticide use is not reduced.

The European parliament and EU member states still have to approve the commission’s proposal, with a decision expected early next year. The organisations say this means the Dutch government and parliament must act now.

MPs from D66 and GroenLinks-PvdA have submitted a motion to parliament instructing caretaker agriculture minister Femke Wiersma to argue against the proposed relaxation in Brussels. A vote on the motion is expected later on Thursday.

In 2023, the lower house voted against continued approval of the herbicide glyphosate, amid concerns about possible health risks. The then agriculture minister chose to abstain in the EU vote, leaving the substance authorised.

Wiersma has so far said there is no conclusive proof that the pesticides in question are harmful.

In 2024, European research led by Wageningen University showed that 42% of Dutch farmland has excessive levels of nitrogen and phosphates, in addition to widespread contamination with pesticide compounds. Research is also ongoing into a higher incidence of Parkinson’s in the bulb growing areas in the Netherlands.