Cases of people with Parkinson’s disease are exploding worldwide, with a 30% increase in the Netherlands over the past 10 years, a new study based on data contributed by hundreds of doctors has shown.

The research, published in the Lancet medical magazine, shows 11.8 million people now have Parkinson’s compared to 6.2 million only five years before.

The number of Parkinson’s sufferers has doubled over the last 25 years and it is expected to have doubled again by 2040.

In the Netherlands the number of patients has risen by 30% in the last ten years and incidences may be accelerating, Radboud teaching hospital neurologist Bas Bloem told broadcaster NOS.

“In the last four years, the number of diagnoses at five of the hospitals we are working with has risen by 25%,” he told the broadcaster.

Bloem said the new report, which he says may underestimate the number of sufferers, is “poignant”. “Parkinson’s is one of the most cruel things that can happen to people. It affects motor functions, you can’t think clearly, sex, peeing and pooing and sleeping become more difficult,” he said.

In another recent study, Bloem together with an American colleague, explored the link between Parkinson’s and pollution, particularly from the large scale use of pesticides in agriculture.

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.

“I am convinced Parkinson’s is a man-made disease,” Bloem said. The introduction of extremely neurotoxic pesticides such as the now banned Paraquat in the 1970s probably marked the start of what is now an explosion of cases, he said.

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It can take decades for Parkinson’s to manifest itself but in the Netherlands cases of people in their 20s or 30s are becoming more common.

Bloem is particularly worried about the use of glyphosate which has been approved for use in Europe until 2033. “Some 10 studies suggest a possible link to Parkinson’s but we are not sure if it is a cause. The biggest problem with it is that we don’t know whether it’s safe because the European food safety authority did not take Parkinson’s into account properly,” Bloem said.