The first is the toxicity problem. Some researchers believe that the artificial extraction and addition of genes may increase and accumulate the original trace toxins in foods while achieving the desired effects of some people.
Followed by allergic reactions. People who are allergic to food sometimes have allergies to foods that they were not allergic to. For example: Scientists add a certain piece of corn to the genes of walnuts, wheat, and shellfish. Proteins also grow with genes. Going in, then, people who previously eat corn allergies may be allergic to these walnuts, wheat, and shellfish.
The third issue is nutrition. Scientists believe that foreign genes will destroy nutrients in food in a way that people do not currently understand.
The fourth is the resistance to antibiotics. When scientists add a foreign gene to plants or bacteria, the gene is linked to other genes. After people take this improved food, the food will pass the resistance genes to the pathogenic bacteria in the human body and make the body resistant to drugs.
The fifth is the threat to the environment. Many genetically modified varieties contain bacterial genes extracted from bacilli that produce a protein that is toxic to insects and pests. In a laboratory study, a butterfly larvae died or developed abnormally after eating the pollen of a milkweed plant containing the bacillus gene, causing another worry among ecologists. Other species that are not within the scope of improvement may be victims of improved species.
In the end, biologists are worried that in order to cultivate some of the more excellent characteristics, such as having greater resistance to pests and diseases and drought resistance, and the improvement of crops, their characteristics are likely to be transmitted to wild species through pollen and other media.