Mark Purdey's battle has been long and lonely - and he's paid a price in
his private life. But he makes no apology for being obsessive. "A
society needs extremists," he says, "they need obsessive individuals who
can really get to the root of something".
Contrary hypotheses, if they don't "pan out", still sharpen the science.
Summary:
BBC, MARCH 21, 20001 - The Phillips Inquiry into BSE confirmed that the
pesticides could make animals more susceptible to the disease. Not for
the first time, Mark Purdey had made a connection that the official
scientists had missed.
Edward Stourton The man from the Ministry had come with an order for the
treatment of Warble Fly - a parasite which lays its eggs under the skin
of cattle. Like all beef and dairy farmers in the area, Mark Purdey was
told he had to use an organophosphate pesticide on his livestock to
eradicate the infestation.
But he fought the order in court - and he won. When BSE was identified
two years later Mark Purdey noticed that the areas where the disease was
emerging more or less correlated with those where the organophosphates
had been used against Warble Fly. His conclusion that the pesticide
caused BSE turned out to be mistaken.
But nearly twenty years later the Phillips Inquiry into BSE confirmed
that it could make animals more susceptible to the disease. Not for the
first time, Mark Purdey had made a connection that the official
scientists had missed. . .
NICHOLAS REGUSH, ABC NEWS - What if it turns out that the human form of
mad cow disease is triggered by environmental factors - and not by
infectious beef products - as some ongoing British research at Cambridge
University suggests? What if much of the science to date, focusing on
contaminated meat, has been overly simplistic or even dead wrong? The
immediate implication would be that we would have to rethink everything
already done to fight the disease, both in Britain where it began, in
Europe, where it has spread, and in other nations, including the United
States, where concerns are mounting about its potential to be unleashed.
. .
The viewpoint held by most scientists is that an infectious agent likely
moved from sheep to cows and gained enough strength in its cross-species
jump to ravage the nervous system and cause the bovine brain to appear
spongy and rife with holes like Swiss cheese. This brain-destroying "mad
cow" infection was further transmitted, according to this
interpretation, via the rendering of carcasses, to meat and bone meal in
feed. . .
But not according to David Brown, a biochemist at Cambridge University,
who counters that "there is no conclusive proof that [mad cow disease]
caused vCJD." Next week at a scientific conference in Quebec City, he'll
discuss some of his most recent research, pointing to a possible
environmental explanation of both mad cow disease and vCJD. That
conference is all about manganese, a heavy metal, that is essential to
life and is part of the daily diet - for example, wheat, rice and tea
provide the metal - but numerous studies show that environmental
overexposure to it can be dangerous to the nervous system. . .
David Brown agrees with the conventional view that the key agent in the
disease is a protein called a "prion." These prions are thought to keep
nerve cells stable. The conventional view holds that prions can somehow
become malformed and that's when they become infectious and capable of
damaging the brain. The malformed prion, then, according to the
conventional view, is the infectious and transmissible agent in mad cow
disease and vCJD. The infection is neither a virus, nor a bacterium.
Brown parts company here with the conventional view, altogether
dismissing the notion of an "infectious" prion. He told me: "I have
[published] evidence from my cell culture experiments that shows
manganese can change the prion into its abnormal [and dangerous] form."
This is especially the case when the supply of copper to the cell is
low. If David Brown's research is on a correct path, then scientific and
public concerns about infection from beef could eventually be dwarfed by
concerns about toxic effects in the environment that cause copper levels
to decrease and manganese levels to rise. . .
Brown's research has given a boost to the controversial theories of Mark
Purdey, a farmer turned amateur scientist who has been challenging the
conventional view of mad cow disease and vCJD from the start. He has
provided detailed reports to the British government's hearings on mad
cow disease and has published several peer-reviewed scientific papers on
the subject, including data on how manganese in the environment may play
a role in both mad cow disease and vCJD.