Healthy soil and sustainable growing

["Tradingpost" <tradingpost@lobo.net>]

Consequences of GM crop contamination 'are set to worsen'
http://www.guardian.co.uk/science/2008/feb/18/gm.contamination

    * James Randerson in Boston
    * guardian.co.uk,
    * Monday February 18 2008
   
The consequences of contamination between GM crops and non-GM varieties
will be much more serious with the next generation of GM crops, an
influential group of US scientists has warned.

Mixing between GM and non-GM varieties has already caused serious economic
losses for producers in lost sales and exports. But the consequences of
mixing will be much more serious with new crops that are altered to produce
pharmaceuticals and industrial chemicals, the scientists argue. The crops
could harm human health and be toxic to wild animals.

"What would be the impact societally, economically if for example,
cornflakes were contaminated by some sort of drug or chemical? I think it
would be a vast impact economically," said Karen Perry Stillerman, senior
food and environment programme analyst with the Union of Concerned
Scientists.

"I think it's really hard to say [what impact contamination would have]
because there is a variety of different drugs and chemicals that might be
manufactured in plants this way," she added. "Our perception is that some
of them might be toxic, but all of them would certainly cause tremendous
economic upheaval."

The group presented its findings at the American Association for the
Advancement of Science conference in Boston.

Huge research effort

Up to now, commercial GM varieties have been restricted mainly to
modifications for herbicide tolerance or resistance to pests. But a huge
research effort is going into a new generation of crops that are
genetically modified to produce drugs, hormones, vaccines and industrial
chemicals such as the precursors of plastics.

Although public opinion in Britain and the rest of Europe remains firmly
against GM crops in general, it is more favourable to crops with medical
benefits. But the Union of Concerned Scientists said that these are
precisely the crops that pose the greatest risks if they exchange genes
with wild relatives or conventional versions of the same crop.

So-called "pharma crops" can offer advantages over current methods of drug
manufacture. Vaccines produced this way could be grown cheaply in
developing countries and simply given to patients in the food. That would
remove the need for sterile needles and refrigerators to keep vaccine doses
cold - a major obstacle for delivering therapies in poor countries.

Prof Paul Gepts, a plant geneticist at the University of California, Davis,
said past experience suggests that "contamination" events cannot be
avoided. "Gene flow is really a regular occurrence among plants. So if you
put a gene out there it's going to escape. It's going to go to other
varieties of the same crop or to its wild relatives," he said. "It's clear
that zero contamination is impossible at present."

Major economic losses

There have been a handful of examples in the US and elsewhere of genes from
GM varieties not cleared for human consumption getting into nearby food
crops and hence the human food chain. This has led to major economic losses
for producers in lost sales, exports and clean-up costs, but there have
been no proven cases of damage to human health.

"With the products we are talking about, there's the potential for that to
be much more serious than what we have seen so far," said Prof Robert
Wisner at Iowa State University.

According to Gepts, most of the ideas for keeping crops apart are
inadequate, because pollen and seed are carried on the wind, by animals and
birds and on farm machinery. He said the only way to be sure that food
crops would not be contaminated by drug genes or genes for industrial
chemicals would be to use non-food crops such as tobacco.

Alternatively, GM food plants could be grown in greenhouses or underground
to prevent pollen escaping, he said.

Call for ban

The Union of Concerned Scientists is calling on the US Department of
Agriculture to ban the growth of GM pharma crops outdoors unless they are
species that are not eaten by people or livestock.

The USDA is currently putting together new guidelines on GM that are
expected to be completed by the end of the year. Currently, no GM crops
that produce industrial chemicals or pharma crops are grown commercially,
although there are some field trials under way in the US.

Similar issues will apply in the UK and Europe if pharma crops are
approved. So far, though, only a handful of GM crop varieties are grown in
Europe.