Could GMOs Potentially Cause Leukemia in Humans?

The widespread use of foods with genetically modified organisms (GMOs) has long been a cause of concern for health-conscious consumers. Sixty-four countries around the world now require foods containing GMOs to be labeled as such. Despite numerous consumer initiatives in the United States to introduce GMO labeling, the Food and Drug Administration so far has resisted enforcing the labeling of genetically altered foods.

If you’re wondering about the safety of GMOs, a new study may provide yet another reason to stay cautious. The study indicates that biopesticides engineered into GMO crops to make the crops resistant to pests, may be contributing to blood abnormalities ranging from simple anemia to blood cancers like leukemia. The study was published by the Department of Genetics and Morphology at the University of Brazil in the Journal of Hematology & Thromboembolic Diseases.

Bt spore-crystals have been in use in US agriculture since the late 1960’s as an insecticide applied to crops. However, with the advent of recombinant DNA biotechnology, Bt toxin-producing genes have become inserted into the plants themselves. Genertically engineered plants containing Bt toxins have been commercially produced in the U.S. since the mid-90s, and they are now ubiquitous in the US food supply.

In September, 2012, a link between genetically modified food and cancer was confirmed in a French study on rats. The current study goes further and reveals that different binary combinations and doses of Bt toxins can target mammalian cells, in particular, red blood cells, resulting in cell changes that indicate significant damage, such as anemia. The study also found that Bt toxins suppress bone marrow proliferation, resulting in abnormal lymphocyte patterns found in some types of leukemia.

Researchers in this study fed mice various doses of GMO toxins called Cry proteins or Cry toxins. After only one dose, the toxins caused a number of blood abnormalities, which continued to worsen until the seventh day after that single exposure. Damage was seen in the bone marrow cells, ranging from anemia at the lowest dose tested, to higher counts of white blood cells, which are associated with leukemia.

These results, according to researchers Mezzomo and Miranda-Vilela at the University of Brazil, indicate the need for further studies to clarify the mechanism involved in the hematotoxicity found in mice, and to establish the toxicological risks to mammals – before concluding that these GMO control agents are indeed safe for human health.

In short, the jury is still out when it comes to the safety of GMOs for human consumption. If you prefer to play it safe until the health effects of GMOs are more fully ascertained, a little bit of smart shopping can help you stay clear of most of the foods currently containing GMOs. 

Source: Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice. Journal of Hematology & Thromboembolic Diseases, Volume 1, Issue 1.