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Is genetically-modified talong safe to eat?


If there’s one pest that causes so much damage to eggplants, it’s the Eggplant Fruit and Shoot Borer (EFSB). 
 
Scientifically, it is called “Leucinodes orbonalis,” a moth species prevalent in Asia and Africa. The moths’ larvae feed inside the eggplant fruits making it unmarketable and unfit for human consumption.
 
EFSB feeds almost exclusively on eggplant. An entire crop can be lost from EFSB infestation. 
 
“The EFSB can cause as much as 50-75 percent loss of fruits,” said former Science Secretary Emil Q. Javier. “The worm of the insect bores tunnels in the fruit, rendering them unfit for consumption."
 
The current methods used by some eggplant growers in controlling the EFSB, however, are unacceptable, said Dr. Emiliana Bernardo, a member of the Department of Agriculture’s Scientific and Technical Review Panel which reviews and assesses the safety of gene modified foods.
 
Many eggplant farmers spray chemical insecticides every other day, or up to 80 times per growing season to control EFSB infestation in their farms, pointed out Dr. Bernardo, an entomologist or a scientist who studies insects.
 
The practice is unacceptable and unhealthy to consumers, farmers and the environment, Dr. Bernardo said, adding that studies conducted in major eggplant producing provinces found that almost all farmers use chemical insecticides and that some even dip the unharvested eggplant fruits in a mix of chemicals just to ensure that harvests are marketable.
 
Unfortunately, there is no known genetic resistance to EFSB in cultivated and wild eggplants. 
 
“The insects are concealed in the shoots and fruits and are difficult to reach,” said Dr. Javier, who is the president of the National Academy of Science and Technology. “Thus, in order to protect their crops, farmers spray their plants almost every other day with insecticides.”
 
The birth of Bt
 
One possible solution is to introduce Bacillus thuringiensis (Bt) into the vegetable crop, thus giving birth to Bt talong. 
 
Bt talong was developed by genetically engineering a gene from the bacteria so that the GM eggplants now produce a protein that defends it against insect attacks,” explained Dr. Michael Purugganan, a Filipino plant geneticist who is the Dean of Science at the New York University.
 
Bt, a common soil bacterium, produces a protein that paralyzes the larvae of some harmful insects, including EFSB. “When ingested by the larvae of the target insect, the Bt protein is activated in the gut’s alkaline condition and punctures the mid-gut leaving the insect unable to eat. The insect dies within a few days,” noted a briefing paper circulated by the International Service for the Acquisition of Agri-biotech Applications (ISAAA).
 
Bt is present in the Philippine soil and had been in use for years without any harmful effects. As it comes from the earth itself, Bt is very natural, according to Dr. Bernardo. In 1901, Bt was discovered to have an insecticidal property. By 1950s, it became a well-known biological insecticide.
 
“Bt is easily cultured by fermentation,” the ISAAA briefing paper said. “Thus, over the last 40 years, Bt has been used as an insecticide by farmers worldwide. Organic farming has benefited from Bt insecticide, as it is one of the very few pesticides permitted by organic standards.  The insecticide is applied either as a spray or as ground applications. It comes in both granules and liquefied form.”
 
But despite this, there are those who are oppose with Bt talong or anything related to genetically-modified organisms (GMOs). “By transferring genes across species barriers which have existed for eons, we risk breaching natural thresholds against unexpected biological processes,” said Dr. Peter Wills, a theoretical biologist at Auckland University.
 
According to the American Academy of Environmental Medicine, “GM foods pose serious health risks in the areas of toxicology, allergy and immune function, reproductive health, and metabolic, physiologic and genetic health.”
 
Still a GM food
 
GM foods have been linked with food allergies. Jeffrey M. Smith, founder and executive director of the Institute for Responsible Technology, said that soon after GM soy was introduced in the United Kingdom, reports of allergic reactions to soy products skyrocketed by 50 percent.
 
Antibiotic resistance can get worse, Smith claimed. “Antibiotic resistance is already a huge public health problem, and GM foods may well make it worse, since certain genes (such as ones that come from bacteria) used in the process can combine with disease-causing microbes in the environment or in the guts of animals or people who eat them,” he said.
 
“We are not anti-GMO. We are not anti-development or anti-technology,” Daniel Ocampo, sustainable agriculture campaigner for Greenpeace Southeast Asia, was quoted as saying.  Testing of GMOs, he added, “should be confined in the laboratory, not in the fields.”
 
Last June, 2013, the Court of Appeals struck a blow to GM crops in the Philippines by its decision to stop field trials for Bt talong. By September, the court ruled with finality its previous decision.
 
“The (court’s) decision undermines the Philippines’ leading role and regional competitiveness in biotechnology in Asia, possibly discouraging needed domestic and foreign investments in agriculture,” said the Joint Foreign Chambers (JFC) in a recent statement.
 
For their part, Filipino scientists challenged opponents of the field testing of Bt talong to show proof that biotech crops pose serious risks to humans. Results of 12 years of tests on GMOs showed biotech crops do not cause any harm to humans and the environment.
 
“We have had so many field testing with no proof or evidence that GMOs have harmed the environment or the Filipino people,” said Dr. Desiree M. Hautea, Bt eggplant project leader.
 
Low risk, but is it safe? 
 
The question is: Is the Bt protein found in Bt talong safe to non-target organisms? On tests conducted on dogs, guinea pigs, rats, fish, frogs, and even birds, the Bt protein was found not to have any harmful effects, according to Extension Toxicology Network (Extoxnet), a pesticide information project of several US universities.
 
“The specificity of Bt for its target insects is one of the characteristics that make it an ideal method of biological pest control,” the ISAAA briefing paper said. “The specificity rests on the fact that the toxicity of the Bt protein is receptor-mediated. This means that for an insect to be affected by the Bt protein, it must have specific receptor sites in its gut where the proteins can bind. Fortunately, humans and majority of beneficial insects do not have these receptors.”
 
According to Dr. Bernardo, cooking the Bt talong can completely denature the Bt protein. “It is non-detectable in any cooked food therefore there is no human exposure to Bt proteins in eating cooked Bt crops,” she said.
 
On the other hand, the US Environmental Protection Agency has already administered toxicology assessments, and Bt proteins have already been tested at relatively higher dosages.
 
According to the Extoxnet, “no complaints were made after 18 humans ate one gram of commercial Bt preparation daily for five days, on alternate days. . .Humans who ate one gram per day for three consecutive days were not poisoned or infected.”
 
If that is not comforting enough, here’s what the GM Science Review Panel of the United Kingdom says about genetically-modified (GM) crops: “For human health, to date there is no evidence currently commercialized GM crop varieties or foods made from them, are toxic, allergenic or nutritionally deleterious. On balance, we conclude that the risks to human health are very low for GM crops currently on the market.”  — KDM, GMA News