Editor's note: David Schubert is professor at the Salk Institute for Biological Studies.
(CNN) -- Most people like to know what they are eating. However, labeling for genetically modified organisms is not required in any state. This is largely because of the money expended by GM seed producers toward blocking food-labeling laws.
A common claim made by this group is that GM foods have been proved safe to eat and that there is a global scientific consensus to support this statement; therefore, no labeling is needed.
However, an examination of the scientific data, along with discussions on this topic in other countries, show that both claims are blatantly false. What is the evidence that some GM foods are hazardous to human health and that consumers should be able to make a choice based upon this information?
When GMOs were introduced nearly 20 years ago, there was the promise of crops with increased yields and resistant to flooding and salt. Since then, traditional breeding methods have created commercial varieties with these traits, while genetic engineering has created none. For example, recently published data show that conventional breeding of corn and soy increases yields to a greater extent than GM technologies.
With the promise of reducing the use of agricultural chemicals, most of the current GM crops are supposedly either insect or herbicide resistant. In reality, GM crops have fostered an epidemic of herbicide resistant weeds and insects that are no longer killed by the built-in toxins.
The result is a massive increase in herbicide use -- an additional 527 million pounds over the past 16 years. The major herbicide, glyphosate, is found inside the GM plants we eat, leading to its detection in people. Future GM crops will likely trigger a greater use of more toxic herbicides such as 2,4-D, a component of the Agent Orange defoliant deployed in Vietnam. In addition to these problems, there is increasing evidence that GM crops and the chemicals required for their production are harmful to humans.
An Associated Press story in October documented the large increase in cancer and birth defects in commercial farming areas of Argentina since the introduction of GM crops. These data confirm recent animal studies showing that GM corn and the herbicides sprayed on it caused a dramatic increase in cancer in the same strain of rats used in FDA drug safety tests. Another large study showed an increase in severe stomach inflammation in pigs caused by GM feed containing insecticidal toxins, a condition that would likely lead to cancer in humans.
Since it takes many years for diseases such as cancer to appear, we could be reaching that point in time after the introduction of GM crops. What has been the reaction in the rest of the world to this and similar information?
The European Union has tightened its GM food safety testing requirements as consumers continue to reject GM foods, resulting in the withdrawal of investment from two large GM seed producers, Monsanto and BASF. India, Peru, Bolivia, the Philippines and Mexico have issued moratoria on GM food crops to go along with Japan, South Korea and a large number of other countries.
Scientists in Russia have proposed a total ban on all GM products. And China, which initially embraced the technology, is having an extended debate about GM crops. The world's food authority, Codex Alimentarius, agreed in 2011 that GM food labels are justified to trace back any adverse health effects of GMOs.
As a result of these new revelations about GM technology, the industry is making a major public relations effort to promote itself, often falsely claiming that there is a "consensus" among scientists that the technology is safe.
It is critical for the public to educate itself about the realities of GMOs and not be fooled by the rhetoric from companies that sell it.
Most of the world has studied this issue and concluded that GMOs are not worth the risk. Passing GM labeling initiatives in states will be the initial demonstration that the public understands what is at stake.
At the very least, labeling may help reverse the unsustainable trend in this country towards ever increasing industrial GMO farming.
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The opinions expressed in this commentary are solely those of David Schubert.