John Mark Purdey (25 December 1953 – 12 November 2006) was an English organic farmer who came to public attention in the 1980s, when he began to circulate his own theories regarding the causes of bovine spongiform encephalopathy (BSE or "mad cow disease").
He suggested this cause might be Phosmet, a systemic organophosphate insecticide that was being spread along the spines of intensively farmed cows to eradicate warble fly.
[4] Purdey believed that the chemicals, derived from military nerve gases,[1] disturbed the balance of metals in the animals' brains, namely reducing copper and increasing manganese, giving rise to the misfolded proteins called prions that are regarded as the cause of BSE.
Through the High Court, he successfully challenged the British government's compulsory warble fly eradication program, which would have compelled him to treat his own cattle with the insecticide.
"[7] He later speculated that Parkinson's and Alzheimer's may have similar biochemical triggers and pathways as transmissible spongiform encephalopathies (TSEs or prion diseases).
[2] Nonetheless, Purdey's views have not been accepted by mainstream scientists, mainly because official UK response to the epidemic conflates transmissibility with susceptibility.
Purdey's scientific inquiries were based on his field work at outbreak hot spots worldwide and analysis of documentary evidence, thus his papers are mainly theoretical and contain no original biochemical clinical research.
The theory that BSE was caused by a reaction to the use of organophosphorus compounds (OPs) poured on cattle as systemic pesticides cannot be reconciled with the epidemiology and is not supported by research.
[14] His anti-establishment views, his doggedness, and his willingness to educate himself brought him some high-level contacts in the UK, including the Prince of Wales and Lord King, the former defence secretary, who regarded Purdey's work as a "classic piece of scientific investigation.
"[15] Teresa Gorman, MP for Billericay, and Ted Hughes, the poet laureate, were also supporters, while readers of The Guardian contributed to a fund to help pay for his research into BSE and its human equivalent, Creutzfeldt–Jakob disease (CJD).
GM Watch reported that Purdey's research and field work indicates organophosphate and manganese exposure could increase the incidence of death, contrary to the claims of some corporations.