Mark Purdey

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").

Investigations into BSE 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 also became aware of a fact also considered by the Philips Inquiry: "1145. The practice in the UK of recycling animal protein as an ingredient of animal feed dates back to at least 1926. In the 1970s attention was directed within MAFF to the danger that this practice would result in the spread of infectious diseases. The diseases considered were those caused by conventional viral and bacterial organisms. No consideration appears to have been given to the risk that scrapie might be recycled in sheep, or even transmitted to other farm animals. This may seem surprising. The answer probably lies in the fact that half a century had elapsed without any indication that animal feed containing ovine protein was infecting sheep or any other animal." Purdey published a number of papers in which he set down his belief that BSE was a transmissible disease that 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,

In his later papers on BSE, Purdey suggested in his modified hypothesis that a combination of high manganese and low copper in the soil, together with high environmental oxidising agents, might "initiate a self-perpetuating free radical mediated neurodegenerative disease process (e.g., a TSE) in susceptible genotypes." He later speculated that Parkinson's and Alzheimer's may have similar biochemical triggers and pathways as transmissible spongiform encephalopathies (TSEs or prion diseases). 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. Purdey called himself an "underground scientist" and "eco detective." Australian and CDC reports differed in material aspects from the Phillips Inquiry by differentiating causation and susceptibility. An uncritiqued, unpublished report stated broadly that Purdey's modified hypothesis did not fit the spatial distribution of reported incidences, There is also bias in comprehending, interpreting and reporting the conclusions of Purdey, other scientists, and even the Phillips Inquiry (which actually stated: "1123. 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. One experiment has, however, given some limited support to the possibility that the OP phosmet might modify the susceptibility of cells to the prion disease agent.").

He was educated at Haileybury College, Hertfordshire, but was reportedly expelled after his A-levels.

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 Urwin, with whom he had four daughters and two sons. They married one year before his death. He died of a brain tumour on 12 November 2006 on his farm in Elworthy, West Somerset.

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).

In 2001 the European Commission Health and Consumer Protection Directorate-General differentiated between BSE transmission and BSE susceptibility, stating that the main problem in determining factors that increase susceptibility to BSE was the very limited data set which could not substantially confirm or deny possible factors.

As more data and research has occurred, Purdey's theories still appear relevant although untested. As the incidence of BSE and vCJD returns to previous low levels, data which would be useful in determining susceptibility become sparse. Meanwhile, research emphasis on animal models has properly been focused on determining the modes of transmission. Purdey and others theorized possible similar causative factors such as the matching prions identified in later BSE and vCJD studies.

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.

Papers by Purdey

"Auburn university research substantiates the hypothesis that metal microcrystal nucleators initiate the pathogenesis of TSEs," Med Hypotheses, 2005 Oct 12. "Metal microcrystal pollutants; the heat resistant, transmissible nucleating agents that initiate the pathogenesis of TSEs?," Med Hypotheses, 2005;65(3):448-77. "Elevated levels of ferrimagnetic metals in foodchains supporting the Guam cluster of neurodegeneration: do metal nucleated crystal contaminants evoke magnetic fields that initiate the progressive pathogenesis of neurodegeneration?," Med Hypotheses, 2004;63(5):793–809. "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. "Chronic barium intoxication disrupts sulphated proteoglycan synthesis: a hypothesis for the origins of multiple sclerosis," Med Hypotheses, 2004;62(5):746-54. "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. 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. "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. "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. "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. "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 "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. "Are Organophosphate Pesticides involved in the Causation of Bovine Spongiform Encephalopathy (BSE)? Hypothesis based upon a Literature Review and Limited Trials on BSE Cattle," J. Nutritional Med., 1996 4 43-82.This paper questions the conventional wisdom that spongiform encephalopathies, particularly bovine spongiform encephalopathy (BSE), are solely due to ‘infection’ with an ultrafiltrable particulate protein called a prion. The literature is reviewed and data and circumstantial evidence are presented to support the hypothesis that the BSE epidemic was initiated as a result of a combination of factors—genetic, nutritional and chronic exposure to mutagenic organophosphate pesticides which disrupt the genetic pathway of prion protein synthesis. Possible mechanisms are discussed and the broader implications for modern farming practices inspected. "Mad Cows and Warble Flies," Ecologist. 1994 24 (3) 100–104. "Degenerative Nervous Diseases and chemical Pollution," Ecologist, 1994 24 (3) 100–104. "Mad Cows and Warble Flies: a Link between BSE and Organophosphates?," Ecologist. 1992 22 52–57. "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.