Food poisoning from organics proves Ewen-Street should get his facts right
Green Party MP Ian Ewen-Street should take care to get the facts right when he rushes into print promoting organic
farming, the Chairman of the Life Sciences Network, Dr William Rolleston said today.
"The only food scare in recent history in New Zealand stemmed from the farming methods of organic farmers and others who
use unconventional farming practices.
"In late February this year New Zealanders were regaled with stories about 'killer zucchini' which had developed high
levels of natural toxins and been sold on the vegetable market. The result was several recorded cases of people
suffering food poisoning in the Canterbury area.
"Now it turns out that, where the growers were able to be identified, a significant proportion were organic growers.
"An examination of common factors shows the levels of toxin apparently increased among zucchini growers who did not
spray their crops. Unusual climatic conditions meant there were huge numbers of aphids about in January and insect
predation is sometimes associated with increased levels of toxins in plants.
"A literature review by Crop & Food scientists showed there was no direct research to show increased levels of the particular toxin (cucurbitacin) in
zucchini fruit as a result of insect activity, though it has been shown in leaves. Neither does this research mean the
contamination did not result from insect activity. More research will need to be done to establish the facts.
"Of greater relevance was the clear link between increased toxin levels and older open-pollinating varieties of seeds.
"The Royal Commission on Genetic Modification was told many times by organic growers of their preference to save seed
from previous crops. It is likely zucchini grown from saved seed will therefore be more vulnerable to toxin build-up.
"The reviewing scientists are very clear that the most likely cause of the build up of toxins is a genetic weakness in
older varieties.
"This is a clear case where the growers' decision to use older varieties and to save seeds is likely to have resulted in
a health risk for consumers - something which has never happened with crops derived from genetic modification.
"It is possible the problem may have been exacerbated by the pressure put on the zucchini by insect predation.
"To the extent there was an insect problem this could have been avoided through use of the same sprays which all
conventional vegetable growers use to limit insect damage, and to make their crop safe for consumption.
"Mr Ewen-Street should acknowledge that, in this case, the organic growers should have responded to the insect
infestation with pesticides, or withdrawn their product from the market for food safety reasons. Organic production
methods sometimes impose risks to the health of consumers and that certifying food as organic does not make it safe.
"Mr Ewen-Street should further acknowledge that all food production methods carry risks; that human error and failure to
follow the right procedures are the biggest food safety risks we face - not new technology.
"Those who live in glass houses should not throw the first stone Mr Ewen-Street," concluded Dr Rolleston.
For further information, contact:
Dr William Rolleston Francis Wevers
Chairman Executive Director
Phone 03 612 6688 Phone 04 916 0100
Mobile 025 246 0634 Mobile 021 916010