The End of Food. Thomas F. Pawlick

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       The structure of brominated compounds closely resembles that of PCBs, prompting scientists to suspect that the two have similar biological effects. “There is no reason to believe that these things will be any different than the PCBs,” said Ross Nystrom, an adjunct chemistry professor at Carleton University in Ottawa who has worked on the research project. “They look the same. They’ve got the same kinds of chemicals in them, and so far most of the research seems to be saying they behave the same.” ³⁴

      In the past, birds contaminated with PCBs have had offspring with severe birth defects, “including extra limbs, malformed eyes and deformed beaks. Research on children suggests PCBs diminish intelligence.” ³⁵

      Are the BDEs detected in wild gulls likely to turn up in the eggs of domestic poultry, or at some other point in the food chain leading to humans?

      No one knows.

      DIOXIN One of the legacies of the decades-long American attack on Vietnam was the effect of the Dow Chemical Company herbicide Agent Orange on the environment and people of Vietnam, and upon the U.S. servicemen and -women accidentally exposed to it. Visitors to Vietnam today can tour museum exhibits of the grossly malformed victims of the U.S. campaign to deny Vietcong guerrillas the cover of forests and farms by chemically destroying the tree and crop cover of the entire nation. Thousands of crippled children, and horridly malformed fetuses, were part of the effort to “destroy this place in order to save it” from what then-Secretary of Defense Robert McNamara later admitted was a tragically exaggerated, and mistaken, fear of “falling dominos.”

      Now the same substance that destroyed the lives and happiness of so many Vietnamese children and so many American veterans has turned up in the North American food supply—dioxin, known to biochemists as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

      Medically, dioxin is described as: “a toxic, cancer-causing chemical. Initial exposure to this agent can produce chloracne [generalized acne], liver injury, and peripheral neuropathy [muscle weakness, impaired reflexes, and numbness, stinging and burning sensations].³⁶ It has been branded as a cause of severe birth defects. Long-term exposure to the substance can weaken the human immune system and cause cancerous tumors.³⁷

      North Americans, of course, are not being sprayed by the infamous Agent Orange, but they are subject to a never-ending barrage of dioxin, produced as a byproduct of numerous industrial manufacturing processes. Once released into the environment, dioxin tends to concentrate in certain food products, especially meat and other animal products such as eggs.

      Canadian newspaper readers were shocked in 2002 by reports that dioxin—forbidden by law in any food sold in Canada—had been detected in foods imported from the U.S. in quantities up to 18 times higher than internationally accepted limits. “Eight out of 10 samples of pork, beef, and cheese contained chemical byproducts known as dioxins, even though the law stipulates that no such chemicals should be present in food sold in Canada,” said the report.³⁸

      The World Health Organization (WHO) says dioxin levels in meat and animal byproducts must not exceed three parts per trillion for each gram of fat, if health and safety are to be maintained. But samples tested by the Canadian Food Inspection Agency (CFIA) found that a batch of eggs imported from the U.S. had dioxin levels of more than 90 parts per trillion—some 18 times higher than the limit set out by the WHO.

      “By comparison, the dioxin content in a sample of Canadian eggs was 20 parts per trillion”³⁹ CFIA tested beef had dioxin levels of 23 parts per trillion, while cheese samples registered 12 parts per trillion.

      Dioxin is also present in most fish caught by sport fishermen in North America, concentrating especially in the fatty tissues of salmon, trout, carp, and catfish. The danger posed is serious enough that some government departments, like the Ontario Ministry of the Environment, publish annual guides for fishermen, warning them away from badly polluted areas and estimating how much fish they can safely eat from various lakes.⁴⁰ Dioxin is also one of a mix of toxins found increasingly in farmed salmon, which recent studies have found are more contaminated than wild salmon.⁴¹

      Only a few months after the alarming CFIA report, the U.S.-based Institute of Medicine (IOM) issued a warning to North American women, that they should “cut back their consumption of red meat, poultry and whole milk to reduce their exposure to dioxin.”⁴² According to this warning, dioxin “can build up in the body and, in their childbearing years, harm their babies.”⁴³

      “Because the risks posed by the amount of dioxins found in foods have yet to be determined, we are recommending simple, prudent steps to reduce dioxin exposure while data are gathered that will clarify the risks,” said Robert Lawrence, associate dean of the school of public health of Johns Hopkins University and chairman of the IOM committee that issued the warning.⁴⁴

      At the time of the advisory, the U.S. Environmental Protection Agency (EPA) reported that 150 kilograms of dioxins were released into the atmosphere in the U.S. in 2001, up from from 100 kg a year earlier.

      In short, this deadly substance, which so devastated the population of Vietnam, is now present to such an extent in American and Canadian foods that women who plan to have children in future are advised to avoid eating meat, eggs, and dairy products altogether.

      GENETIC MATERIAL (IN GENETICALLY MODIFIED, OR GM, FOODS) When the first genetically modified (GM) food products began to appear on the market, a skeptical public immediately branded them “Frankenfoods,” and reacted with suspicion. This reflex was ridiculed by the foods’ corporate manufacturers as emotional and unscientific, but there is good cause to think that hesitation to accept the starry-eyed predictions of GM foods’ most enthusiastic boosters may be no more than prudent common sense.

      After nuclear power, the most controversial scientific advance of the twentieth century has been genetic engineering. Whole libraries have already been written on the subject, and as the twenty-first century began, it seemed the controversy was likely only to deepen.

      The term genetic engineering refers to the manipulation of any genetic material, such as DNA (deoxyribonucleic acid), for practical uses. Normally, this involves introducing foreign genes into microorganisms so as to change their genetic code—and thus their basic nature.

      First modeled in 1953 by British scientist Francis Crick and the American J. D. Watson, the “double helix” structure of the DNA molecule is the basic building block of the chromosomes contained in the nuclei of living cells, and carry within them the biochemical hereditary information–the codes–that determine the structure and function of most living creatures. Those codes consist of individual genes, segments of DNA that specify particular traits such as (in you and me) hair color, sex, body build, and so forth.

      As anyone knows who has read Mary Shelley’s nineteenth-century novel Frankenstein, or the modern Prometheus, or even seen the host of Hollywood productions based on it (my personal favorite is the 1931 Boris Karloff version), playing around with the basic stuff of life can get messy, resulting in things the players never expected, much less intended– and genes are, in every sense of the expression, the basic stuff of life.

      Obviously, GM techniques hold enormous promise, particularly in medicine where they may eventually lead to cures for some of humankind’s worst physical and mental afflictions. Applied in the field of agriculture, they hold just as much promise—and terrible dangers. The latter come under two headings: 1) the effects of GM foods on human health and, 2) the effects of GM crops on their surrounding environments.

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