Thursday, November 06, 2003

GM Foods

Back in August I asked for some real science to be brought to bear on the GM foods debate. When I wrote that, I didn't know that a 4 year farm scale study into some GM foods was nearing its end. The results were published in mid-October, but are not available online (at least not that I could find).

The first I saw about this was on RTE's web site on Oct. 16. I saw this and felt that perhaps GM foods are not all they're cracked up to be:
campaigners against the growing of genetically modified crops have welcomed the results of field trials carried out in Britain over the past three years. They say they show the alleged benefits of GM do not exist. The field trials found that some GM crops were worse for wildlife than conventional crops.
However, I never trust RTE, so today I decided to go back and see what I could find.

The Guardian's report from Oct. 17 provides a fuller picture. Apparently, the primary problem is that genetically modified beet and rape allow farmers to more effectively control weeds. This increased weed control leads to a reduction in the food supply for some birds and insects. However (and this is a big however), the opposite is the case with GM maize (corn to us Americans).

So, science does indicate that growing certain GM crops can have a negative effect on wildlife in the area where these crops are grown. Does this mean we should ban the growing of these crops? That depends. How badly do we want to improve our farmers' yields? How much of a decline in the populations of insects and birds should we expect if we allowed these crops to be grown? Could farmers grow GM foods in a way that would minimize this effect on birds and insects? And, is it possible that improvements in the herbicides used with conventional crops could have the same effect anyway?

Trevor Sargent claims that "contamination of conventional and organic crops can occur within a 16 mile radius of a GM trial site" according to the "latest UK scientific research". However, these field studies involved growing conventional crops side-by-side (fields were divided in half) with the GM crops and I would have imagined that if contamination was going to occur, it would have occurred in these fields. The Guardian doesn't mention anything along these lines, so presumably, Mr. Sargent's information is from some other report.

This investigation deals entirely with the impact that growing GM foods can have. Science still claims that eating GM foods is in no way harmful to people. This Royal Society report from 2002 indicates that
the risks to human health associated with the use of specific viral DNA sequences in GM plants are negligible. Given the very long history of DNA consumption from a wide variety of sources, it is likely that such consumption poses no significant risk to human health, and that additional ingestion of GM DNA has no effect.
This report also discusses some of the risks associated with conventional plant breeding as a comparison with genetically modified.

Two key questions arise with regards to genetically modified food:
  1. Is it safe to grow?
  2. Is it safe to eat?
The answer to the second question seems an emphatic YES, while the first is (currently) yes/no depending on the crops to be grown and the extent to which we want to allow them to be grown.