Sound science has debunked yet another purported biotech scare, as the Environmental Protection Agency on October 16 declared biotech corn perfectly safe for monarch butterfly consumption.
A 1999 study reported in the journal Nature claimed a high death rate among monarch caterpillar larvae fed milkweed leaves dusted with high doses of pollen from genetically modified corn. The story was quickly trumpeted by the anti-technology lobby and the mainstream media as a stark warning against animal and human consumption of “Frankenfoods.”
The corn at issue had been genetically modified to produce a small amount of toxin specifically targeting a moth larva called the European corn borer. The genetic modification had been widely acknowledged to exclusively affect the corn borer until the Nature study challenged that belief.
NAS confirms safety
EPA thus ordered a round of studies to determine what threat, if any, the biotech corn posed. On September 14, 2001, the National Academy of Sciences reported the results of the numerous studies, all concluding that biotech corn posed no hazard to monarch butterflies or any other creatures other than the corn borer.
“The potential for adverse effects of Bacillus thuringiensis (Bt) Berliner corn . . . on nontarget organisms has received much attention since a correspondence to Nature suggested that pollen from Bt corn could be hazardous to the larvae of the monarch butterfly,” noted the NAS studies’ abstract.
However, the abstract continued, “Ecological risk is a function of exposure (environmental dose) and effect (toxicological response). The amount of pollen dusted on to the milkweed leaves was not quantified in the initial study; as a result, it is not possible to establish a relationship between pollen exposure and effect from these [Nature] data.”
The NAS noted that the Nature conclusions were based on force-feeding the butterfly larvae nothing but pollen-dusted leaves in doses far greater than the larvae are exposed to in biotech cornfields. The NAS scientists concluded that in real-world conditions, there would be no more than five deaths out of every 10,000 butterfly larvae eating biotech corn pollen deposited on milkweed leaves. That number compares favorably to the death rates of larvae eating all sorts of other food sources found naturally in their environment.
“Bt corn has been evaluated thoroughly by EPA, and we are confident that it does not pose risks to human health or to the environment. The safeguards incorporated into these registrations will ensure that farmers can continue to use an effective, low-risk pest control alternative, which helps to protect the environment by reducing the amount of pesticides used,” stated Steve Johnson, assistant administrator of the EPA Office of Prevention, Pesticides and Toxic Substances.
Safer than nature
Henry Miller, a fellow at Stanford University’s Hoover Institution and former head of the Food and Drug Administration’s Office of Biotechnology, noted that biotech corn is not only a non-risk factor to the environment, but in fact makes the environment safer for all manner of plants and animals.
“Food from gene-spliced organisms is, on average, even safer than other food, because the technique is more precise, circumscribed, and predictable than other techniques, and new, insect-resistant varieties of grain crafted with gene-splicing have lower levels of contamination with toxic fungi and insect parts than conventional grains,” explained Miller.
“Thus, gene-spliced corn is not only cheaper to produce but is a potential boon to public health. Moreover, by reducing the need for spraying chemical pesticides on crops, it is environmentally friendly.”
Specifically regarding biotech corn and monarch butterflies, Miller observed that, “In fact, areas with large-scale cultivation of gene-spliced corn around the country showed increased numbers of Monarchs. Moreover, recall that the alternative to planting this corn variety that has increased intrinsic pest resistance is not the absence of any intervention, but spraying the broad-spectrum chemical pesticides, which would decimate butterflies and other beneficial insects.”
Miller further observed that more than 60 percent of processed foods in the U.S. contain ingredients derived from gene-spliced organisms, and yet there has never been a reported injury to a person or the environment as a result of biotech foods.
