How We Establish Biotech Crop Safety: Product Characterization

By K. Sauer 3/30/2009

What is substantial equivalence?

The concept of substantial equivalence is widely accepted as the basis for proving the safety of biotech crops. It was introduced by the Organization for Economic Cooperation and Development (OECD) in 1993, and has been validated by many international scientific and governmental organizations since.

According to the Biotechnology Industry Organization's (BIO) Web site, "simply stated, substantial equivalence holds that a biotech food is as safe to consume as an existing food with the same compositional and nutritional characteristics and a history of safe use." Basically, if the biotech crop has the same make-up and nutrients as its conventional counterpart, it's considered as safe as that counterpart. Learn more about the history of and details behind substantial equivalence.

We constantly see or hear story lines claiming biotech crops cause cancer or biotech crops have led to an increased rate of food allergies, among others.

Unfortunately, headlines like this cause concern among consumers. Regardless of what critics and many story lines say, there’s one thing we know—food derived from authorized genetically-modified (GM) crops is as safe as conventional food.

But how do we know this?

Millions of farm animals have consumed nutritious feed rations made with grain from biotech crops and people have consumed hundreds of millions of meals containing foods derived from biotech crops—all without a single substantiated instance of illness or harm due to the GM ingredient.

However, it goes beyond this.

Before we submit a biotech crop to regulatory agencies for approval, it has undergone numerous tests by our research teams to ensure and prove it’s as safe as its conventional equivalent. In February 2009, Monsanto’s regulatory division held a Food and Feed Summit in St. Louis, Missouri. Gary Bannon, Monsanto’s product characterization and detection methods center lead, and Kevin Glenn, Monsanto’s product safety center lead, explained these tests to employees.

Characterizing a New Biotech Product

“[In the Product Characterization Center], we’re responsible for the determination of the safety of the gene itself—the inserted DNA—and the protein that is produced by that particular insert,” Bannon said.

The first order of business is proving they’ve only inserted the intended gene and nothing else.

“If you look at the gene or DNA that we insert, we have to satisfy the regulator that we’ve inserted one copy, that the copy is intact, and that we have not inserted any other portions of the DNA of the plasmid we used for plant transformation into any other portion of the genome of the organism,” Bannon said.

“We want to be sure we put in exactly what we say we put in, that it’s in the correct sequence and it’s not going to be interfering with a critical gene that is already in the plant genome,” he continued.

Along with the research verifying the gene has been inserted correctly, Monsanto also demonstrates the protein produced by the new DNA is safe for human and animal consumption. The first step is to show the naturally occurring protein in conventional crops is substantially equivalent to the protein made by the biotech crop. These equivalence studies involve studying the biochemistry of the protein and making sure it functions the same as the protein in the biotech crop.

When looking at the safety of the protein, Monsanto looks for several things, the most important being a history of safe use.

“The history of safe use is extremely important because it will define how far we have to go to [show] the safety of that protein,” Bannon said.

There are four categories used to show a history of safe use. The first is safety of the donor organism, which means if the gene—and therefore the protein—comes from a bacterium that is not a human or animal pathogen, it’s considered safe. To date, no pathogenic proteins have been used in biotech crops.

The second category is familiarity, which basically asks if the protein is unique, or if it’s been in food and feed in one form or another before. This is proven using algorithms that are well-accepted by international scientific and governmental organizations to compare the new protein and amino acid sequences to proteins from existing organisms.

Taking familiarity one step further is exposure, the third category. Exposure asks if people and animals have come into contact with the protein before and if it’s already in food and feed. If so, we are well on our way to establishing a history of safe use because it’s already been consumed and there haven’t been any reports to show it has harmed people or animals.

Finally, we look at the estimated consumption rate, which means we look at how much of the protein will actually be in food and feed—and therefore how much people or animals have the potential to consume. These will then be used to determine margins of exposure or safety, which is done by the toxicologists in the Product Safety Center, where the overall risk of the product is determined.

And that’s where part two of this story picks up.