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DIABETES IS INCREASING
A new study confirms that Vietnam veterans have an increased likelihood of getting diabetes if they have elevated levels of dioxin in their blood.[1] Dioxin is a powerful hormone-disrupting chemical found in Agent Orange, an herbicide sprayed by American forces during the Vietnam war.
Recent studies have also indicated that diabetes is increasing among the general population in the U.S.[2] and worldwide. The increase is especially rapid among children.[3,4] At the recent 16th International Diabetes Conference in Helsinki, Finland, researchers said that diabetes is becoming a global epidemic. "I think we can truly say that the epidemic is here and now," said Paul Zimmet, chief executive officer of the International Diabetes Institute.[5]
Diabetes is a disease of the endocrine system.[6] Specifically, diabetes is a disorder of the pancreas, which is a long, thin organ (roughly 7 inches long), behind your stomach. The pancreas produces hormones that help digest your food, but the pancreas has another important function as well: it creates hormones that regulate your body's use of glucose, a form of sugar that fuels most of the daily activities of all your body's cells.
The pancreas produces three hormones: insulin, glucagon, and somatostatin. When the concentration of sugar rises in your blood (for example, after a meal), insulin stimulates muscle and fat cells to remove glucose from the blood and store it. Insulin also stimulates storage of excess glucose in the liver in the form of a starch called glycogen.
When more sugar is needed in the blood, the pancreas produces the hormone glucagon to break down glycogen in the liver and turn it back into sugar, which is then released into the blood stream. The third pancreatic hormone, somatostatin, is not so well understood as the other two but is thought to help regulate sugar levels in the blood.
When the pancreatic system fails to control glucose properly, the blood can end up containing too much sugar --a condition called hyperglycemia. Eventually the excess sugar is measurable in the urine. When a person's body is not able to use up the available glucose in the blood, the person has DIABETES MELLITUS (Greek words for 'honey that passes through').
There are two kinds of diabetes --insulin-dependent diabetes mellitus (IDDM), and non-insulin dependent diabetes mellitus (NIDDM). IDDM is also called Type I diabetes, or juvenile-onset diabetes because it usually appears during childhood. As the name implies, IDDM requires a person to take insulin, usually by daily injections. Ten percent of diabetics have IDDM.
The other kind of diabetes --NIDDM --does not require a person to take insulin injections. The person's insulin levels are about normal, but their body seems unable to make good use of insulin. They must control their blood sugar by controlling their diet. NIDDM is also called adult-onset diabetes, or Type II diabetes. It usually appears after age 40, and the people who get it are usually obese. Ninety percent of diabetics have NIDDM.
Diabetes is a serious illness. Its main effect is to cause changes in the body's small and large blood vessels. These changes, in turn, lead to other problems: coronary artery disease, heart disease, high blood pressure, stroke, deterioration of nerves and blood vessels in the extremities (sometimes requiring amputation), blindness, kidney disease, and death.
The symptoms of diabetes are vague --tiredness, thirst, and a need to urinate frequently as the body tries to flush away excess blood sugar. For this reason, many people have the disease for years without knowing it. There are 10 million known diabetics in the U.S. and perhaps 5 million more who have not been diagnosed.[6]
Vietnam veterans
The new study of Vietnam veterans looked at dioxin levels in their blood and related that to sugar and insulin levels in their blood, and to the prevalence of diabetes and the time-of-onset of diabetes.[1] The study compared 989 veterans who had participated in Operation Ranch Hand (spraying roughly 12 million gallons of Agent Orange over 10% of South Vietnam during the period 1962 to 1971) vs. a control group of 1276 Air Force veterans who served in Southeast Asia during the same period but did not participate in the herbicide spraying program. During manufacture, Agent Orange was contaminated unintentionally with dioxin at a level of about 3 parts per million (ppm).
The median dioxin level in the serum of the Ranch Hand group was 12.2 parts per trillion (ppt) and the median dioxin level in serum of the control group of veterans was 4.0 ppt. (Blood serum is the fluid remaining after cells are removed from blood.)
The researchers found that the Ranch Hand veterans were about 50% more likely to get diabetes, compared to the control group. In addition the severity of diabetes increased within the Ranch Hand group as the level of dioxin in blood increased. And lastly, the time-to-onset of diabetes was less among the Ranch Hand veterans who had more dioxin in their blood. The study found consistent increases in the likelihood of glucose (blood sugar) abnormalities with increasing dioxin.
Among the control group, the researchers noted an increasing likelihood of abnormally high levels of insulin in blood serum as dioxin levels increased.
Previous studies of industrial workers exposed to dioxin had given mixed results. Some showed increases in likelihood of diabetes with increasing dioxin,[7] while others had shown no such increases.[8] Six studies of three species of laboratory animal (rats, mice, and Guinea pigs) have shown alterations in glucose metabolism with low levels of dioxin exposure, thus increasing the biological plausibility of the idea that dioxin might cause diabetes.[9]
General population
As indicated above, IDDM is largely a disease of children. On the other hand, NIDDM, is largely a disease of adults. Now, however, NIDDM is striking more and more children. Prior to 1992, among pediatric patients with diabetes, only 2% to 3% had NIDDM. In other words, 97% to 98% had IDDM.[3] In recent years, however, there has been a dramatic increase in the number of children diagnosed with NIDDM. In a study of youngsters in Cincinnati, Ohio, in 1994, NIDDM accounted for 16% of all new diabetes cases. Among diabetes patients 10 to 19 years of age in Cincinnati, NIDDM accounted for 33% of diagnoses of diabetes in 1994.[3] This represents a 10-fold increase in NIDDM among children in recent years.
Obesity has been increasing among children in recent years as well. Between 1980 and 1990, the proportion of children defined as obese increased from 15% to 21%.[4] The Cincinnati researchers clearly see these two trends as linked.
The Cincinnati researchers asked themselves whether their results could be caused by greater general awareness of NIDDM among physicians. Or by earlier detection and referral. Or by changes in the general population of Cincinnati in recent years. They ruled out all these potential confounders and concluded that the increase in NIDDM among children is very likely a real increase.
Why are more children getting this adult disease? Many researchers have noted a relationship between obesity and diabetes in both adults and children. Indeed, in the Cincinnati study, 92% of 1027 children with diabetes were obese.
However, there is, so far, no known biological mechanism to explain how the presence of excess body fat might cause diabetes.
The finding that an endocrine-disrupting chemical like dioxin may be able to promote diabetes opens up new avenues for thought about this rapidly-increasing disease. Perhaps it isn't fat itself that causes diabetes --perhaps it is the toxic chemicals stored in our fat that cause disease. It has been known for a long time that human fat accumulates toxic chemicals. For example, the U.S. Public Health Service has been collecting samples of fat from humans for 20 years and analyzing them for halogenated hydrocarbons,[10] including dioxin, beta-hexachlorocyclohexane, heptachlor, DDT, DDD, DDE, PCBs, trichloroethylene, perchloroethylene, 2,4-D, methyl chloride, vinyl chloride, polyvinyl chloride (PVC), and chloroform, among others. We each carry literally hundreds of exotic toxic chemicals in our body fat. For any particular chemical, our fat often has a concentration 100 times as high as the concentration in our blood serum. It is also known that chemicals can be released from fat to re-circulate in the blood stream during times of pregnancy, stress, illness or fasting. Many fat-stored organohalogens are known to interfere with our endocrine systems by mimicking or blocking natural hormones.[11]
Diabetes is on the rise worldwide. "I expect diabetes to be one of the major killers of the world in the year 2010," says Jak Jervell, president of the International Dia- betes Federation.[5] Worldwide, an estimated 135 million people have been diagnosed with diabetes. By 2025, the World Health Organization predicts, the number will be 300 million. "What is bothering me is that the developing world will bear the brunt of this increase," says Jervell. He was referring to people adopting an American lifestyle: fatty fast food, with little or no physical exercise. But there's another key feature of American life that we often don't advertise: from exposure to water, food, and air, we all take a bath more or less continuously in low levels of exotic, poorly-understood toxic chemicals, many of which interfere with our hormones. No doubt about it, for many people it's a wonderful life. But the price we pay in chronic disease is high and steadily rising.[12]
--Peter Montague
COME BEAR WITNESS TO INJUSTICE
Next Thursday, August 14 at 4:30 p.m. a silent vigil will help us all bear witness to the huge injustice represented by the WTI incinerator in East Liverpool, Ohio. (See REHW #255, #287, #288, #298, #315, #320, #325, #326, #328, #341, #542.)
At 6:30 that evening, the U.S. EPA will once again hold a public hearing to explain to the citizens of East Liverpool why their children must attend an elementary school 1100 feet from the stack of the largest hazardous waste incinerator in America.
On May 8 EPA released its 3800-page risk assessment on the WTI incinerator and sent one copy to one citizen in East Liverpool. On May 9 EPA held a public hearing in East Liverpool to take testimony on the risk assessment that no one had seen, much less read. Peer reviewers were given 10 days to review the 3800 pages and send their comments to EPA. One day after the deadline for peer review comments -- May 20th -- EPA issued the full commercial operating permit to the WTI incinerator.
Words cannot express the outrage and disgust that we feel. Has there ever been a government agency more arrogant or more cynical than William Jefferson Clinton's (and Carol Browner's) EPA? Come bear silent witness with us. At the East End Elementary School in East Liverpool, Ohio at 4:30 pm. (Don't know where it is? Come to town and ask.) And at the EPA public hearing in City Hall at 6:30. Be there if you can. This is one of the most important citizen fights of this century. We must never concede victory to the forces of evil -- the Von Roll Corporation and its corrupt acolytes in Washington. --Peter Montague
A NEW GLOBAL PROBLEM
A new global environmental problem has emerged from an unexpected source: nitrogen. Nitrogen makes up 78% of Earth's atmosphere; however, in its atmospheric form nitrogen is an unreactive gas, unavailable to most living things. Now a new peer-reviewed report from the Ecological Society of America (ESA) portrays nitrogen as a triple threat: warming the planet via the greenhouse effect, damaging the Earth's protective ozone layer, and reducing biodiversity (the diversity of species upon which ecological stability ultimately rests).[1] ESA is the nation's professional organization for ecologists. Ecology is the branch of biological science that deals with the relationships between organisms and their environment.
Nitrogen problems arise when human activities --mainly industrial agriculture and combustion of fossil fuels --"fix" nitrogen out of the atmosphere by combining it with hydrogen or oxygen. In its "fixed" forms, nitrogen becomes biologically active. Other human activities (burning grasslands and forests, draining wetlands, clearing land for crops) move nitrogen out of long-term storage, making it available to living things.
Two big natural forces fix nitrogen from the atmosphere: lightning and microorganisms, many of which work together with legumes (for example, peas, beans, and alfalfa) and algae. As every farmer knows, planting legumes adds nitrogen to the soil because microorganisms on the plants' roots fix nitrogen from the atmosphere.
Nitrogen fixation in the oceans is poorly understood; however, on the land, natural forces fix somewhere between 90 and 140 million metric tonnes (MMT) of nitrogen per year. (A metric tonne = 1.1 tons, or 2200 pounds.) Of this, lightning accounts for perhaps 10 million metric tonnes (MMT) and microorganisms account for the rest.
Human activities now fix something just over 140 million metric tonnes (MMT) per year, thus doubling (or more) the amount of biologically active nitrogen on the land, according to ESA. Doubling a natural flow of a chemical like nitrogen is "an enormous effect on a global cycle," says Dr. William H. Schlesinger of Duke University, one of the authors of the new ESA report.[2]
Until 1940, human industrial activities fixed almost zero nitrogen. Therefore biologically available nitrogen has increased very rapidly. The ESA report says, "The immediacy and rapidity of the recent increase in N[itrogen] fixation is difficult to overstate." Indeed, a study in 1990 found that half of all the nitrogen ever fixed by industrial processes has been produced after 1980.
Many of the Earth's plant species are adapted to --and function best in --soils and waters containing low levels of available nitrogen. By doubling the amount of available nitrogen, and by increasing the movement of nitrogen from place to place, humans are disrupting ecosystems on a grand scale. "No place on earth is unaffected," says the ESA report. Here is a listing of some of the problems identified by the ESA report:
** Nitrous oxide (N2O) added to the atmosphere is a potent greenhouse gas, allowing sunlight in but refusing to allow heat to escape, thus tending to warm the planet (just the way the glass roof over a greenhouse captures the sun's energy and warms the greenhouse). Nitrous oxide presently accounts for "a few percent" of the global greenhouse gas problem, says the ESA report.
** When it reaches the stratosphere (6 to 30 miles up in the sky) nitrous oxide contributes to the destruction of the Earth's ozone shield. Reducing the ozone shield in turn increases the ultraviolet radiation striking the surface of the Earth which, in turn, damages some of the creatures that form the bottom of the oceans' food chains,[3] and may harm other creatures (including humans) as well.[4]
Nitrous oxide is increasing in the atmosphere at the rate of 0.2% to 0.3% per year. It comes from many sources: fertilizers, nitrogen-enriched groundwater, nitrogen-saturated forests, burning of biomass (grasses and forests), land clearing for crops, and manufacture of nylon.
** Nitric oxide (NO) plays a key role in creating toxic ozone near the ground. Ozone is the most harmful common air pollutant to humans and vegetation. Ozone and other nitrogen compounds are key components of the smog that now envelopes large areas of the planet, especially urban areas.[5]
** The final product of oxidizing NO is nitric acid, a key component of acid rain, which is damaging forests in Canada, the U.S. and Europe. Combustion of fossil fuels is the main source of nitric oxide (20 MMT per year), followed by biomass burning (8 MMT per year). Human sources now account for 80% of all atmospheric NO.
** NH3, or ammonia, injected into the atmosphere is a major source of nitrogen movement between ecosystems. Each year, fertilizer contributes 10 MMT of ammonia to the atmosphere; domestic animal wastes contribute 32 MMT, and biomass burning adds 5 MMT. Humans contribute 70% of all the ammonia reaching the atmosphere.
** As a result of all these contributions of fixed nitrogen to the atmosphere, fixed nitrogen is deposited back on land and oceans at an increased rate. In the midwestern and eastern U.S., nitrogen deposition from the atmosphere onto the land is more than 10 times as great as the natural rate. In parts of northern Europe nitrogen deposition is now more than 100 times as great as the natural rate.
** Nitrogen deposited on the land tends to move into nearby waters, carrying with it calcium and magnesium from the soil. As a result, both the soils and the receiving waters tend to become more acidic. After calcium in the soil has been depleted, then aluminum begins to move into nerby waters with the nitrogen. Aluminum is toxic to many aquatic species.
As sulfur dioxide emissions have been curbed in recent years, nitrogen has become better-recognized as a source of acidification in lakes. As areas of land become nitrogen-saturated (meaning, they can't absorb any more of it), nitrogen run-off and consequent acidification are increasing.
Another effect of all these changes is to create nutrient imbalances in trees. Such imbalances can lead to reduced photosynthesis, reduced forest growth and even to increased tree deaths, according to the ESA report.
** Ecologists in Minnesota treated 162 plots of land with varying amounts of nitrogen and examined the results.[6] After 12 years they found three important changes:
1. Some plant species disappeared completely, driven out by others that thrived better in a high-nitrogen environment. The result was a loss of biodiversity as "weedy" species took over and the land became biologically impoverished.
2. When these weedy species died, their higher nitrogen content put more nitrate nitrogen into the soil. Nitrate is highly soluble in water and moves readily into local streams. In high concentrations, nitrate is toxic to humans; at lower concentrations it can cause blooms of algae, depleting oxygen and upsetting the balance of aquatic ecosystems.
3. Because the weedy plants were rich in nitrogen, bacteria and fungi that feed on nitrogen decomposed them rapidly. Because of the rapid decomposition, these plants did not capture and retain any more carbon than the plants they had displaced. This was a disappointing discovery. Ecologists had hoped that, by encouraging plant growth, high nitrogen levels would capture increased carbon, thus reducing the threat of global warming from carbon dioxide, the main greenhouse gas. It turns out not to work that way. Evidently, planting trees won't get us out of the global warming jam.[7]
** The nitrogen content of the Mississippi River has more than doubled since 1965, and nitrate concentrations in the major rivers of the northeastern U.S. have increased 3-to 10-fold since 1900, according to the ESA report. The same is true of European rivers. Nitrogen from rivers is now reaching the Atlantic Ocean at rates 2 to 20 times as great as during pre-industrial times. Around the North Sea, the increase has been 6-to 20-fold.
** Nitrogen entering the oceans is causing fertilization and eutrophication of estuaries and coastal seas: "...it represents perhaps the greatest threat to the integrity of coastal ecosystems," says the ESA report. Eutrophication is the excessive growth of plants, leading to oxygen deficiency which has killed significant numbers of fin fish and shellfish in the Chesapeake Bay, Long Island Sound, the Black Sea, the Baltic Sea, and elsewhere.
Nitrogen-fed algae blooms have been identified as the source of a major outbreak of cholera in South America in 1991. The algae harbor the cholera-causing bacterium. In 1991, 500,000 people fell ill and 5000 died when cholera erupted along the coastline of Peru and quickly spread to 18 other countries.[8]
These nitrogen problems are not going to be easy to solve. The ESA report says, "The momentum of human population growth and increasing urbanization ensure that industrial N[itrogen] fixation will continue at high rates for decades."
The ESA report suggests that, by 2020, industrial agriculture will be contributing 134 MMT per year, up 68% from the 80 MMT it contributes annually today. And by 2020, fossil fuel combustion will be contributing 46 MMT per year, about twice its present contribution.
Obviously these projections could prove wrong if the corporations promoting industrial agriculture and fossil fuel combustion could be brought under control. The Ecological Society of America's report does not consider this possibility. In the section, "Future Prospects and Management Options," the report only considers slightly-less-wasteful ways of using nitrogen fertilizer on industrial farms.
Disappointingly, ESA's report never acknowledges the really viable alternative to industrial farming, which is ecological farming that seeks to mirror and maintain the natural ecology in which it is practiced.[9]
As the ESA report documents to a dismaying degree, the industrial farming model is leading to widespread deterioration of global ecosystems. It is not sustainable.[10]
Instead of the Henry Ford model, which aims to alter natural ecological neighborhoods to maximize short-term yields of a few specialized crops for export to world markets, the organic farming model achieves higher yields[11] using less energy[12] and emphasizes food locally produced for local people with local control.[9] It is an ecological approach that views humans as products of, and partners in, the local ecology, not masters of it.
--Peter Montague
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