A long-running campaign to highlight the health impacts of a dangerous chemical used by farmers in the UK has been vindicated by the conclusions of a major new study.
Several hundred farmers in the UK are believed to have suffered debilitating health problems from exposure to organophosphate pesticides (OPs), as an Ecologist investigation earlier this year revealed. A large number of them were shnvestigationeep farmers, following government orders in the 1980s and 90s to treat their animals with the chemical to protect against the spread of a disease called sheep scab.
Other groups also known to have been affected include veterans from the Gulf War, who were exposed to pesticides to protect them from pests and mosquitoes, and airline pilots and cabin crew, who can be exposed to organophosphates in engine oil.
Derived from World War II nerve gas agents, organophosphate pesticides are the most widely used insecticides in the world. While high-level exposure to the chemicals has long been known to be dangerous, low-levels of exposure of the kind experienced by farmers spraying the chemical or dipping sheep, was not initially thought to be a hazardous, as the government promoted a new chemical-dependent era of farming.
However, with growing reports of health problems from the farmers around the UK since the mid-1980s, including more than 600 reports of ill health to an official surveillance scheme, the government has been under pressure to acknowledge that low-level exposure may have caused widespread illness.
Now researchers from University College London and the Open University have shown that the type of long-term, low-level exposure many farmers using the chemicals will have experienced produces long-term brain damage.
In the first attempt to review the existing scientific evidence, their independent analysis found that 13 out of 16 studies had shown evidence of neurological problems following long-term, low-level exposure to OPs. The health problems reported included poor memory, reduced reaction time, attention disorders and diminished ability to solve complex problems.
Researchers hope the findings will provide belated recognition to many sufferers still alive today and help others who are unaware their medical condition could be related to the use of organophosphate pesticides.
Norfolk arable and beef farmer Peter Dixon, who used OPs throughout the 1980s, 90s and 2000s before suffering worsening health five years ago, said he struggled for many years to work out the reason for his ill health.
"I felt ill, lethargic and weak all the time," he told me, "my GP couldn’t work out what was wrong with me."
It was only after visiting a private physician that Peter was told his symptoms were linked to OP poisoning. After detox treatment, he has partially recovered, but believes many farmers may still be suffering without knowing the cause.
For Teresa Layton, whose husband David suffers from multiple sclerosis and relies on her 24-hour care, the findings are scant relief. She claims that proper warnings about the dangers of using OPs were never passed onto farmers like her husband David, who was eventually confirmed as having suffered OP poisoning.
"It's so frustrating to think of all the things we could have done as a family and with our children which we haven't now been able to do. And all because of this sheep dip product that the government and chemical companies must have known was dangerous and yet still allowed so many peoples' lives be ruined.
The compulsory use of OPs in sheep dipping has long since been stopped and warnings and health and safety procedures, in the UK at least, much improved. Farmers are now required to take a safety course before being allowed to administer these chemicals. However, campaigners have long been maintaining that the government has deliberately tried to avoid confirming the link for fear of compensation claims from affected farmers.
Former farming minister Lord Rooker confirmed as much in a House of Lords debate on OPs in 2009 saying, “I do not want to be controversial but ones gets the impression of a natural reluctance to investigate...Why? Oh, because there are no new cases; because of the issue of compensation; because the science is not quite clear".
Lead-researcher Dr Sarah Mackenzie Ross, from University College London, said she hoped the findings would force the government to reconsider its position.
“This is the first time anyone has analysed the literature concerning the neurotoxicity of organophosphate pesticides, using the statistical technique of meta-analysis.
“The analysis reveals that the majority of well-designed studies undertaken over the last 20 years find a significant association between low-level exposure to organophosphates and impaired cognitive function.”
A spokesperson from the Veterinary Medicines Directorate said the government's Committee on Toxicology (COT) was currently reviewing research on OPs and their link to ill health in humans. "Until the COT’s review is completed, it is not appropriate for Government to anticipate the outcome of the COT’s review."
The review was given to COT in September 2012, but it is understood that members of the committee want further time to assess the evidence before making a statement.
Tom Levitt is a freelancer writer on food and farming issues. You can follow him on twitter at @tom_levitt
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