Monday, October 14, 2013

Are Genetically Engineered Foods Safe?

More personally, do I, as a non-scientist, intend to eat genetically engineered foods?  I would like to make this decision based upon current scientific thinking.  Unfortunately, as is the case with Climate Change, there are websites claiming scientific credentials with contradictory claims.  Given the confusion over the scientific rigor of the claims, it is easy, falling into conformational bias, to simply believe those claims that are most aligned with preexisting beliefs or values.   I am resisting the urge to do just that and have been trying to sort out this politicized scientific debate.  I have tried to avoid sites uploaded by either agricultural concerns with a stake in potential profits or anti-GMA sites that appeared to be presenting an argument rather than the science of it all.

A preliminary question might inquire into identifying genetically engineered foods already on the shelves.  There are claims that 80% of the packaged food on grocery shelves is genetically engineered.  These claims are misleading.  Most processed food contains some sugar and most sugar beets and field corn from which high fructose corn syrup are derived from genetically engineered sugar beets and corn.  Source and Source.  The “80%” claim may be misleading because the sources I have cited report that in the case of sugar, the sequence with the artificially engineered nucleotides is broken down or eliminated in the refinement process (or perhaps the digestive process, which is more problematic for me).  The actual components of natural and genetically engineered DNA are the same.  If the sequences are broken down into their component parts, nothing novel is ingested.

There are some genetically engineered whole foods, including varieties of papaya, sweet corn and some squashes.  Furthermore, I presume that as the agriculture industry becomes more experienced with genetic engineering, the selection of genetically engineered foods will increase accordingly.

Preparing for the new agriscape, I try to not to let my Liberal Aversion to New Technology control my choices.   On the other hand I am skeptical of “progress” promoted by industry.  Industry has historically disregarded the public commons.  Capitalism has no mechanism to prevent pollution, exploitation of resources or otherwise consider  long-term negative consequences of industrial action.  And even if we imagine a fully responsible industrial decision there is the problem of unintended consequences.

Genes are composed of DNA strands. DNA informs the production of proteins. When DNA is genetically engineered, the DNA of an organism will make new or different proteins and/or suspend production of other proteins previously manufactured by the non-engineered organism. Proteins, in turn, play critical roles in biologic function. Proteins have required roles in the creating and maintaining structures and regulating the function of tissues and organs. When you change the DNA, the proteins are changed and the organism is modified.

The promise of genetically engineered agriculture is that crops can be modified so that plants are more disease resistant, more pest resistant, more drought resistant, more resistant to rot after harvest and can produce a higher crop yield. The benefits might include a more abundant and more stable more food supply. These benefits could be more apparent in less developed areas which tend to have more marginal nutrition.

The concerns about genetically engineered organisms include the introduction of toxicity or allergens in the food supply, vertical contamination of the artificial DNA into the naturally occurring populations of the same species and horizontal contamination of the artificial DNA into the other species.

It is beyond the province of science to confirm that genetically engineered foods are safe. Scientific testing is limited to looking for problems, but the absence of an identified problem is not a conclusive finding of safety. It is always possible that the problems have just not been identified. The limits of the scientific method suggest two conclusions. First, it is unreasonable to demand that science prove GMOs are safe. Secondly, the fact that problems have not been identified does not mean they do not exist.

A complicating factor in this discussion is the fact that genes do not necessarily have a one-to-one correspondence with a specific biologic feature.  A single gene may affect more than one characteristic of an organism and often genes work in combination with each other.  This means that even when a gene is isolated as affecting pest resistance, there may be other functions of that gene acting alone or in concert with other genes that remain unknown.

Every genetic manipulation creates a novel set of biologic questions.  This means that every genetic change must be studied independently.  The fact that a genetic manipulation may have unintended consequences beyond the specific objective and that some of these unintended consequences may only surface as a result of long-term studies means that even those Genetically Modified Foods deemed safe after short-term studies need to be followed looking for clues as to more subtle and long-term differences.

In Washington State there is an initiative on the ballot that would require labeling.  If the people of Washington vote to include genetic information on some food packaging because the information is material to their consuming decisions because of a host of factors including safety, nutrition and market centralization, then the food industry will have to adapt and make those disclosures.  I am concerned, however, about the inconsistencies in the global market.  I believe it would be in the best interest of Washington, as a stakeholder in international trade, to push for labeling uniformity in global trade.  It seems onerous for our agri-business, if they must adjust the labeling based on every destination market.  I would be a louder voice for labeling, if the genetic engineering was taking place in Uzbekistan rather than Creve Coeur, Missouri.

There are environmental concerns independent of human consumption.  Vertical Contamination has already occurred in Oregon wheat and caused severe economic problems. The consequences of Horizontal Contamination are difficult to assess.  However, birds, rodents, insects and bacteria are all regularly interacting with genetically modified organisms.  It may be that the chances of horizontal contamination with animals or even insects are miniscule.  However, the risk seems higher with regard to bacteria or even a virus.  In the non-food sector genetically modified bacteria could help with Climate Change.  It doesn’t stretch the facts much to imagine that a bacteria with some artificial protein could worsen Climate Change.  I believe that it is difficult to assess the risks.  Some have blamed the Bee Colony Collapse on genetically modified organisms, although the cause of that problem may be a different unintended consequence of agri-business pesticide development. 

In a situation such as this I believe the Precautionary Principle is an appropriate standard for setting policy.  Unfortunately, given the difficulty of risk assessment, application of the principle leads to widely divergent results.  A reasonable policy response would require  that environmental as well as human consumption studies are required for each and every genetically modified organism taken outside the laboratory.

A requirement that all genetically modified organisms are sterile and cannot replicate is sensible, but leads to a concern about market control.  Sterile crops require farmers to purchase new seeds every year from the patent holder.  The ultimate result of the requirement of sterility is that the food supply of the consuming nations becomes dependent upon a limited number of agri-businesses, such as Monsanto, holding patents on genetically engineered crops.  A balancing policy would be to require patent-holders to pay for the pre-release studies and the necessary follow-up studies as well as any remedial action in the event of a problem in the same way that industries are responsible for chemical pollution in the event of a spill.  This policy may result in higher prices for genetically modified foods, but the higher price may be closer to the public cost of the technology.

One argument used by some is that genetic engineering is the same as selective breeding which is publically accepted.  First, selective breeding has led to toxic crops, so the argument cannot reassure us of the safety of genetic engineering.  Secondly, selective breeding can only enhance the inherent capability of the organism in question, while genetic engineering is capable of creating entirely new characteristics.  There is a difference in kind between selective breeding and genetic engineering.

To conclude, I believe that there is no scientific reason to assume that currently available genetically modified food products are not safe.  I have been and will continue to consume foods that are genetically engineered.  That being said, I also believe that long-term studies should be carried out to screen for more subtle or delayed problems.  Each new instance of genetic engineering must be independently studied.  Costs and responsibility for precautions should be borne by patent holders.  Studies should monitor environmental contamination as well as human health concerns.  The issue of labeling is best addressed with a global standard.

The scientific voice I find most compelling in this politicized debate is the Union of Concerned Scientists. (Another UCS page).  The UCS has been accused of being unscientifically cautious, but given the uncertain risk-assessment I find their voice responsible rather than reactionary.

Mike Mallory

Further reading:

Sites claiming GMOs are safe enough-






Sites claiming GMOs are not safe enough –