Monday 11 May 2015

Rotten Tomatoes

Like most folks, I’ve carried around this sort of vague idea of how genetic engineering works, with images of white-coated scientists bent over their super microscopes, physically cutting and splicing gene sequences between species to create new varieties. Authorities proclaim them “safe”, anti-GMO folks say they’re not. I climbed on the anti-GMO bandwagon not so much because of safety concerns over GMOs themselves—after all, the US FDA (Food and Drug Administration) tell us they are “Generally Recognized as Safe” (GRAS)—but because they entice farmers to overuse agri-chemical killers (herbicides and pesticides) that many GMO plants are altered to resist.

Reading Steven Druker’s new book “Altered Genes, TwistedTruth: How the Venture to Genetically Engineer Our Food has Subverted Science,Corrupted Government, and Systematically Deceived the Public” has been a profound eye-opener. I think the story from the book that best encapsulates for me the danger, not only of these foods, but also the danger of the cavalier attitude of authorities that are supposedly responsible for our food safety, is the story of Calgene’s Flavr Savr™ tomato. I’d like to briefly share that tale here.

Back in the early 1990s when genetic engineering was in its infancy, California genetics company Calgene (later acquired by Monsanto) took on the tomato. It was well known that consumers preferred vine-ripened tomatoes, but by the time ripe tomatoes were picked, processed, packaged, transported, and landed on supermarket shelves, they had often gone soft. Tomatoes picked green stayed firm, but lacked flavour. Calgene tackled this problem with genetic engineering.

Calgene scientists modified their tomatoes by supressing the PG enzyme that causes fruit to go soft. They did this by copying out that section of the enzyme gene and reversing it, then reinserting the flipped segment back into the enzyme with the aid of the 35s promoter from the cauliflower mosaic virus. (That detail isn’t all that important, except to point out that the process of genetic modification is far more complicated than most folks realize.) The new tomato looked good.

The US FDA encouraged Calgene to do a safely trial on rats, so they did. In that first 28-day trial, some rats ate the GE Flavr Savr tomatoes, some ate ordinary tomatoes, and some ate no tomatoes at all. At the end of the trial, they found that 10% (4 out of 40) of the rats who had eaten the Flavr Savr™ variety had developed stomach lesions (bleeding) while the others hadn’t. Fluke? They hoped so. They tried the test again, and this time 20% of the Flavr Savr™ rats had stomach lesions. So they tried the test a third time, and this time, again, 20% of the Flavr Savr™ rats had stomach lesions, but so did a few of the non-Flavr Savr™ rats. Understandably concerned, the researchers took their results to the FDA.

Some of the scientists at the FDA who looked at the results expressed their serious concerns about the safety of these tomatoes too, but while they were considering what to do, the administrative branch of the FDA brought in a new ruling stating that GM foods were to be considered GRAS (Generally Recognized as Safe) and that safety studies involving animal test subjects need not be done because GM foods are, by definition, “substantially equivalent” to non-GM foods and therefore need no pre-market approval (1992).

Since animal testing was no longer required, results of these rat tests on Flavr Savr™ could be ignored. The FDA ruling allowed Calgene to proceed with Flavr Savr™ production, and Flavr Savr™ tomatoes were brought to the market in 1994 as a premium-price product. They were discontinued in 1997, ostensibly due to Calgenes "inexperience in business."

There is an even more frightening kicker here. In the Flavr Savr™ study documents, there is a small endnote that reports that 7 rats of the original study DIED within two weeks of consuming the tomatoes. The researchers attributed the deaths vaguely to “husbandry”, and replaced the dead rats, apparently DURING THE TRIAL PERIOD, with fresh, healthy rats. Rather than being investigated, this astounding revelation and violation of standard testing practice appears simply as a note in the study.

The Flavr Savr™ tomato did not survive in the marketplace, but the FDA precedent set—that GM foods do not require animal testing because they are assumed safe—and safer than food additives, which do require testing— has survived. I believe this assumption is profoundly disturbing.


I highly recommend Steven Druker’s book. Druker is a public interest attorney, and although at times the book reads more like a legal argument than a general-interest or scientific analysis, it is clear he has done his homework. He helped initiate a lawsuit against the FDA forcing them to release their files on genetically engineered foods, and his specialty area of expertise is food safety.

1 comment:

  1. Thanks, this is an extremely important story about the era of President George H.W. Bush that established "substantial equivalence" as a faux legal position.

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