Mark Purdey

Who was Mark Purdey?

John Mark Purdey 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.

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.