Toxicity From Genetically-Engineered Foods

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Genetically altered food: Buyer beware

By John Fagan

There's a war on in Europe, and most Americans have hardly heard about it. It concerns the safety of something very basic to human life: our food. Why are we so uninformed while European consumers are up in arms and their governments are taking swift action against the uncontrolled introduction of genetically modified foods?

Mention genetically altered foods to most Americans, and you will get a blank stare. A genetically cloned sheep has stolen the headlines. Yet with each passing day, we are filling our grocery carts with these foods in ever-increasing percentages without our knowledge or consent.

In Europe, shiploads of these products have been halted at borders. Supermarket chains and food producers have banned these products from their shelves or promised consumers that they will label these foods conspicuously. In fact, several nations are enacting stringent labeling requirements.

What is at the core of the fear about these new foods? And should this concern derail work some claim will increase agricultural efficiency and reduce world hunger? Scientific journals and leading scientists have joined in the chorus to urge definitive research into the possible risks in advance of mass use by humans.

Scientists have altered foods by inserting into them genes from bacteria and viruses. Many more such products containing foreign DNA from insects, fish and even humans are in the R&D pipeline and soon will be headed for our dinner plates.

Foods altered through genetic engineering often contain proteins and other components that have never before been part of the human diet: proteins from bacteria and viruses and, in the future, proteins from insects, scorpions and people. There is no way to predict whether those foods are safe to eat. The only way to tell is to test them rigorously. Yet our government does not require such testing.

The risks are not hypothetical. Any unbiased scientist familiar with the technology will admit that genetic engineering can give rise to unanticipated allergens and toxins. Already we have seen this scenario in action. In 1989, a dietary supplement, L-tryptophan, caused 37 U.S. deaths and 1,511 nonfatal cases of a disease called eosinophilia-myalgia syndrome (EMS). The Centers for Disease Control linked these cases to tryptophan manufactured using genetically engineered bacteria. A study published in Science in 1990 confirmed that the tryptophan was contaminated with a toxic "novel amino acid" not present in tryptophan produced by other methods.

How could this problem have been prevented? Routine food-safety tests could not have done the job. They can only detect the presence of toxins or allergens known to be present in common foods such as shellfish and peanuts. Such tests on the genetically altered tryptophan would not have registered a blip. Only biological and clinical tests on humans would have revealed the truth. Unfortunately, these tests were not done. Moreover, they are still not required for other genetically engineered foods. Advocates maintain that the risk from any given genetically engineered food is small and argue, therefore, that it is unnecessary to carry out stringent safety testing.

This view is not scientifically responsible. Thousands of these foods products will be brought to market over the next several years. When we do the math, the small risk that any given product will produce unanticipated effects translates into virtual certainty of harm when many new genetically engineered foods have become part of the diet of large populations over extended periods of time.

What is the solution? Given that billions of dollars have been invested in developing these products, we cannot exclude them from the market. Nonetheless, consumer safety must be protected. Here are three suggestions to address both issues: Safety testing must be made more stringent. (Bold) The only scientifically valid approach is to feed these foods to human volunteers and see how they respond. Such testing is required by the FDA before new foods or additives produced by other methods can be marketed. Why should genetically altered foods be an exception? All genetically engineered foods must be labeled as such. Safety testing can never give us a guarantee with 100% certainty. For example, tests extending over three years may fail to detect harmful effects that require five years to emerge. Mandatory labeling gives the consumer choice in whether to accept that risk. Health officials can also better trace the source of any problems if the products are labeled.

The public must be properly informed about the benefits and risks.

Informed choice by consumers will protect the integrity of the biotechnology and food industries and maintain confidence in the American food supply.

Genetically modified foods that have been approved, are awaiting approval or are under development in the USA:

Apples Rice
Barley Soybeans
Beans Squash
Chestnuts Stawberries
Corn Sugar cane
Cucumbers Sunflowers
Lettuce Tomatoes
Melons Tobacco
Peppers Walnuts
Papayas Watermelons
Potatoes Wheat

Source: U.S. Agriculture Dept.

Dr. John B. Fagan is a molecular biologist who has conducted research using recombinant DNA techniques.