John Mark Purdey (December 25, 1953 – November 12, 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").
Purdey's interest in the disease was triggered when four cows he purchased for his farm developed the disease, though no animal raised on his farm ever contracted it. He published a number of papers in which he set down his belief that BSE was not an infectious disease, contrary to the mainstream scientific view, but that it had an environmental cause. 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. Purdey believed that the chemicals, derived from military nerve gases, disturbed the balance of metals in the animals' brains, 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.
In his later papers on BSE, Purdey suggested that a combination of high manganese and low copper in the soil, together with high environmental oxidizing agents, might "initiate a self-perpetuating free radical mediated neurodegenerative disease process (e.g., a TSE) in susceptible genotypes." He also argued that transmissible spongiform encephalopathies (TSEs or prion diseases) are linked to Parkinson's and Alzheimer's. His work was published in a number of minor peer-reviewed journals. He delivered lectures around the world to farmers and academics, and was invited to present his research to the British government's Phillips Inquiry into BSE. He called himself an "underground scientist" and "eco detective." He received a number of awards from New Age and organic farming organizations.
Nonetheless, Purdey's views have not been accepted by mainstream scientists. The Phillips Inquiry concluded that "[t]he theory that BSE is caused by the application to cattle of organophosphorus pesticides is not viable, although there is a possibility that these can increase the susceptibility of cattle to BSE." His papers, published primarily in the journal Medical Hypotheses, are exclusively theoretical and contain no original biochemical research.
Purdey was born in Much Hadham, Hertfordshire, to what The Daily Telegraph describes as a "long line of gifted eccentrics." The Telegraph reports that an ancestor of his reportedly walked from Inverness to London to set up Purdey's gunsmiths, and that, after suffering shell shock during the First World War, his grandfather, Lionel Purdey, lobbied Lord Kitchener to recognize shell shock as an illness that needed treatment.
He was educated at Haileybury College, Hertfordshire, but was reportedly expelled after his A-levels. He turned down a place at London University to study zoology and psychology and, according to The Guardian, "embarked on a kind of post-hippie bucolic existence."
In his mid-twenties, he set up an organic dairy farm, first in Ireland, and later in Pembrokeshire, on which he bred a herd of pedigree Jersey cattle. He wrote on his website that he introduced semen from New Zealand, Denmark, and Canada, in order to produce a "high fat, high yielding, pasture-fed Jersey cow" with an ability to produce milk from a "self-sufficient arable/legume-grass rotational system with minimal reliance upon purchased in concentrate feed." In 1997, one of his cows was the highest yielding Jersey cow in the UK, with 10,150-litre lactation, after she had been sold to a conventional farm. He is reported to have enjoyed playing the saxophone to his cows to keep them calm.
He married Carol MacDonald in 1974, a marriage that produced a son and a daughter. When that relationship broke up, he set up home with Margaret Unwin, with whom he had four daughters and two sons. They married one year before his death. He died of a brain tumour on November 12, 2006 on his farm in Elworthy, West Somerset.
Views of Purdey
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." It was King who, in April 1993, formally alerted the Ministry of Agriculture to Purdey's research, after Purdey forwarded King a letter from Professor Satoshi Ishikawa of Kitasato University, who wrote that Purdey's description "about Mad cows to organophosphates compounds and warble fly is exactly true."
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).
His legal victory attracted letters from farmers who believe that using OP compounds had caused them health problems. Purdey began to educate himself about the science of OPs just as the first recorded case of BSE was confirmed. He became convinced there was a connection, in part because cattle in Britain had been given unusually high doses of OPs; and in part because the theory that BSE was spread by contaminated meat and bone meal (MBM) did not, he argued, explain why the disease was not occurring in countries that had imported the same MBM from the UK.
The Telegraph writes that public support for Purdey increased after the BBC aired a documentary about his theory in 1988.
Papers by Purdey
- "Auburn university research substantiates the hypothesis that metal microcrystal nucleators initiate the pathogenesis of TSEs," Med Hypotheses, 2005 Oct 12. PMID 16226390
- "Metal microcrystal pollutants; the heat resistant, transmissible nucleating agents that initiate the pathogenesis of TSEs?," Med Hypotheses, 2005;65(3):448-77. PMID 15908137
- "The pathogenesis of Machado Joseph Disease: a high manganese/low magnesium initiated CAG expansion mutation in susceptible genotypes?," J Am Coll Nutr, 2004 Dec;23(6):715S-29S. PMID 15637221
- "Elevated levels of ferrimagnetic metals in foodchains supporting the Guam cluster of neurodegeneration: do metal nucleated crystal contaminents evoke magnetic fields that initiate the progressive pathogenesis of neurodegeneration?," Med Hypotheses, 2004;63(5):793-809. PMID 15488650
- "Elevated silver, barium and strontium in antlers, vegetation and soils sourced from CWD cluster areas: do Ag/Ba/Sr piezoelectric crystals represent the transmissible pathogenic agent in TSEs?," Med Hypotheses, 2004;63(2):211-25. PMID 15236778
- "Chronic barium intoxication disrupts sulphated proteoglycan synthesis: a hypothesis for the origins of multiple sclerosis," Med Hypotheses, 2004;62(5):746-54. PMID 15082100
- "Does an infrasonic acoustic shock wave resonance of the manganese 3+ loaded/copper depleted prion protein initiate the pathogenesis of TSE?" Med Hypotheses, 2003 Jun;60(6):797-820. PMID 12699706
- with Bounias M. "Transmissible spongiform encephalopathies: a family of etiologically complex diseases — a review," Sci Total Environ, 2002 Oct 7;297(1-3):1-19. PMID 12389776
- "Does an ultra violet photooxidation of the manganese-loaded/copper-depleted prion protein in the retina initiate the pathogenesis of TSE?" Med Hypotheses, 2001 Jul;57(1):29-45. PMID 11421622
- "Ecosystems supporting clusters of sporadic TSEs demonstrate excesses of the radical-generating divalent cation manganese and deficiencies of antioxidant co factors Cu, Se, Fe, Zn. Does a foreign cation substitution at prion protein's Cu domain initiate TSE?" Med Hypotheses, 2000 Feb;54(2):278-306. PMID 10790765
- "High-dose exposure to systemic phosmet insecticide modifies the phosphatidylinositol anchor on the prion protein: the origins of new variant transmissible spongiform encephalopathies?," Med Hypotheses, 1998 Feb;50(2):91-111. doi:10.1016/S0306-9877(98)90194-3 PMID 9572563
- "The UK epidemic of BSE: slow virus or chronic pesticide-initiated modification of the prion protein? Part 2: An epidemiological perspective," Med Hypotheses. 1996 May;46(5):445-54 PMID 8735882
- "The UK epidemic of BSE: slow virus or chronic pesticide-initiated modification of the prion protein? Part 1: Mechanisms for a chemically induced pathogenesis/transmissibility," Med Hypotheses, 1996 May;46(5):429-43. PMID 8735881
- "Mad Cows and Warble Flies," Ecologist. 1994 24 (3) 100-104.
- "Degenerative Nervous Diseases and chemical Pollution," Ecologist, 1994 24 (3) 100-104.
- "BSE," Ecologist, 2002 32 (9) 33-37.
- "The manganese loaded/Copper depleted bovine brain fails to neutralise incoming shockbursts of low frequency infrasound; The Origins of BSE?" Journal of Cattle Practice ( J of British Cattle Veterinary Association ), 2002 October, Vol 10 (4) p 311-335.
- with Bounias M. "TSEs; a family of etiologically complex diseases," The Science of the Total Environment, 2002 297 (1-3) pp. 1–19.
- "Mark Purdey", The Daily Telegraph, November 18, 2006.
- Mark Purdey, markpurdey.com.
- Purdey, M. "Are Organophosphate Pesticides Involved in the Causation of Bovine Spongiform Encephalopathy (BSE)? Hypothesis Based upon a Literature Review and Limited Trials on BSE Cattle," Journal of Nutritional Medicine, 1994, 4, 43-82; see also Purdey, M. "High-dose exposure to systemic phosmet insecticide modifies the phosphatidylinositol anchor on the prion protein: the origins of new variant transmissible spongiform encephalopathies?", Med. Hypotheses, volume 50, issue 2, pp. 91-111, 1998.
- Biography, markpurdey.com.
- Purdey, M. "Mad Cows and Warble Flies: A Link between BSE and Organophosphates?," The Ecologist, 1992, 22(2), 52-57, cited in "Scientists after Southwood; section 5, Challenges to the Government's approach, Mr. Mark Purdey", Phillips Inquiry, volume 11, p. 304.
- "Scientists after Southwood; section 5, Challenges to the Government's approach, Mr. Mark Purdey", Phillips Inquiry, volume 11, p. 304.
- "Volume 1: Findings and Conclusions. Executive Summary of the Report of the Inquiry. 3. The cause of BSE", Phillips Inquiry, October 2000.
- "Mark Purdey", The Daily Telegraph, November 18, 2006; also see Purdey, Lionel. History of the Purdey Family.
- Woffinden, Bob. "Obituary", The Guardian, November 21, 2006.
- Letter from Satoshi Ishikawa to Mark Purdey", December 22, 1992, cited in "Scientists after Southwood; section 5, Challenges to the Government's approach, Mr. Mark Purdey", Phillips Inquiry, volume 11, p. 304.
- "Tributes to Mark Purdey", markpurdey.com
- Monbiot, George. "Mad cows, Bretons and manganese", The Guardian, November 23, 2000.
- "Farmer says chemicals cause BSE", BBC News, April 2, 1998.
- "Mad Cows and an Englishman" on YouTube, BBC documentary, 2001.
- Connor, Steve. "Mark Purdey: One-man BSE campaigner", The Independent, November 17, 2006.