tagged w/ POPs
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Warming in the Arctic is causing the release of toxic chemicals long trapped in the region's snow, ice, ocean and soil, according to a new study.
Researchers from Canada, China and Norway say their work provides the first evidence that some persistent organic pollutants (POPs) are being "remobilized" into the Arctic atmosphere.
"Our results indicate that a wide range of POPs have been remobilized into the Arctic atmosphere over the past two decades as a result of climate change, confirming that Arctic warming could undermine global efforts to reduce environmental and human exposure to these toxic chemicals," write the scientists, whose analysis was published yesterday in the journal Nature Climate Change.
That's of concern because POPs can travel long distances on air currents, persist in food and water supplies, and accumulate in the body fat of humans and other animals. The pollutants also can be passed from mother to fetus and have been linked to serious health problems in humans and other animals.
Co-author Hayley Hung, a scientist with Environment Canada's Air Quality Division who studies toxic organic pollutants in the Arctic, said that in recent years, researchers had posited that warmer conditions would liberate POPs stored in land, ice and ocean reservoirs back into the atmosphere.
"The chemicals are known to be semi-volatile," Hung said. "They have the ability to evaporate out of storage" -- if temperatures are warm enough.
She and her colleagues began to suspect the phenomenon was already under way when they examined 20 years of air monitoring data collected at a high Arctic monitoring site, Zeppelin Mountain Air Monitoring Station in Norway's Svalbard archipelago.
Toxic blasts from the past
Beginning in the mid-2000s, scientists observed higher levels of certain POPs, including hexachlorobenzene and polychlorinated biphenyls (PCBs), at the Norwegian research station. That stood out, Hung said, because the chemicals' use has been restricted to the point where many POPs are no longer produced. As a result, the level of POPs in Arctic air had been decreasing.
"Stockpiles still exist, but these are limited sources," she said, "and the sources are already known to us. So we were surprised to see concentrations actually coming up at the Svalbard station."
The scientists then examined two decades of monitoring data from the Alert monitoring station in the Canadian province of Nunavut. They saw smaller, though still significant, increases in POPs at the second site.
Hung believes the larger increase at the Svalbard site is caused by its proximity to ocean areas where sea ice has retreated. "This is a sign to us that these chemicals are indeed evaporating out of the ocean," she said.
More at the linkWarming in the Arctic is causing the release of toxic chemicals long trapped in the... more
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http://www/environmentalhealthnews.org/ehs/news/pops-in-food
Thirty-eight years after DDT was banned, Americans still consume trace amounts of the infamous insecticide every day, along with more than 20 other banned chemicals. These legacy contaminants are ubiquitous in U.S. food, particularly dairy products, meat and fish. Their decades-long presence underscores the dangers of a new generation of chemicals with similar properties and health risks.
In a photograph from a 1947 newspaper advertisement, a smiling mother leans over her baby’s crib. The wall behind her is decorated with rows of flowers and Disney characters. Above the photo, a headline reads “Protect Your Children From Disease Carrying Insects.”
The ad, for wallpaper impregnated with DDT, captures a moment of historical ignorance, before the infamous insecticide nearly wiped out many birds and turned up inside the bodies of virtually everyone on Earth.
The story of DDT teaches a lesson about the past. But experts say it also provides a glimpse into the future.
Thirty-eight years after it was banned, Americans still consume traces of DDT and its metabolites every day, along with more than 20 other banned chemicals. Residues of these legacy contaminants are ubiquitous in U.S. food, particularly dairy products, meat and fish.
Their decades-long presence in the food supply underscores the dangers of a new and widely used generation of chemicals with similar properties and health risks.
“They’re manmade, and they’re toxic and they bio-accumulate,” said Arnold Schecter, a professor at the University of Texas School of Public Health who has been studying human exposure to chemicals for more than 25 years. “So the fact that they’re still around a long time after they’ve been banned isn’t surprising.”
Recent studies sketch a complex profile of legacy contaminants in U.S. food - a profusion of chemicals in trace amounts, pervasive but uneven across the food supply, occurring sometimes by themselves, but more often in combination with others. Included are DDT and several lesser-known organochlorine pesticides, as well as industrial chemicals such as polychlorinated biphenyls, or PCBs, which were used until the late 1970s in electrical equipment.
This picture raises a host of equally complicated questions: Are small amounts of these chemicals dangerous, by themselves or in mixtures? Why are they still around and how are they getting into our food?
Think of these chemicals like sand in your shoes after a trip to the beach. Despite our efforts to rid ourselves of it, we discover more later - sometimes that evening, sometimes years later - when we put on the same pair of summer shoes and feel the grains between our toes.
“They’re manmade, and they’re toxic, and they bio-accumulate. So the fact that they’re still around a long time after they’ve been banned isn’t surprising,” -Arnold Schecter, University of Texas School of Public Health Like those grains of sand, many chemicals stick around. They belong to a class called “persistent organic pollutants” or POPs - which take decades to break down in sediment and soil and can travel globally on wind and water, ending up in regions as remote as the Arctic. These migratory POPs, when ingested, take up semi-permanent residence in the fat tissue of living organisms. In animals, and sometimes in humans, many of them can raise the risk of cancer or other diseases, alter hormones, reduce fertility or disrupt brain development.
The good news is that DDT and other organochlorine pesticides, PCBs and industrial byproducts called dioxins have declined significantly in food and the environment since they were banned or restricted decades ago. A few have dipped below detectable levels. “We don’t expect the levels in food or people to go down abruptly, we expect them to go down over time. And that’s what we’re seeing,” Schecter said.
Declining populations of birds of prey are often the first sign of pollution that may threaten people’s health.
Precise trends of chemicals in food are hard to identify because both government and independent studies have focused on different foods in different places at different times. However, levels in human breast milk indicate that, by 1990, DDT had dropped to one-tenth of 1970 levels, according to a 1999 report in the International Journal of Epidemiology. Similar trends exist for PCBs and dioxins. In most places, POPs are a mere fraction of what they were.
Last year, as part of an ongoing study of POPs in the food supply, Schecter and his colleagues collected and analyzed more than 300 samples from supermarkets around Dallas, Texas. The samples were combined into 31 food types, such as yogurt, chicken and peanut butter, and tested for old contaminants as well as newer ones.
“Every food within this study contained multiple pesticides,” the authors wrote in a paper published in February in the journal Environmental Health Perspectives.
The DDT metabolite DDE was the most prevalent, occurring in 23 of the 31 foods sampled.
People consume more DDT than any other persistent organic pollutant, the researchers found. Its relative abundance in food today is due to its widespread historical use. In the United States alone, an estimated 1.35 billion pounds were sprayed to wipe out mosquitoes and agricultural pests over a period of about 30 years, according to the Environmental Protection Agency.
continuedhttp://www/environmentalhealthnews.org/ehs/news/pops-in-food
Thirty-eight years... more
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Swiss researchers have found that Alpine glaciers melting under the impact of climate change are releasing highly toxic pollutants that had been absorbed by the ice for decades.
They warned in a study abstract published in the journal Environmental Science and Technology that it could have a "dire environmental impact" on "pristine mountain areas" as global warming accelerates.
Much of the pollution was dumped on Europe's biggest mountain range by atmospheric currents from further afield, according to the researchers at three Swiss scientific institutes.
Their study of layers of sediment from an Alpine lake formed by a hydroelectric dam built in central Switzerland in 1953 revealed "sharp" build-ups of now banned chemical compounds from industry and farming, including dioxins and pesticides like DDT.
"We can confirm with the help of these layers that, in the 1960s and 1970s, POPs (Persistant Organic Pollutants) were produced in great quantities and were also deposited in this Alpine lake," said one of the authors, Christian Bogdal, of the Swiss Federal Laboratory for Materials Testing and Research.
But while the concentration of POPs fell after the 1970s as many of those compounds were banned, the scientists found an unusual resurgence in more recent sediment from the past 10 to 15 years.
They concluded that the lake, the Oberaarsee, was largely fed by water from a nearby melting glacier that was releasing pollutants at a level comparable to when the compounds were still in use.
"At this stage our study indicates that accelerated glacier melting due to global warming may also account for enhanced release of legacy organic pollutants at historically high levels," according to the full study.
One of the scientists, Peter Schmid, told AFP on Wednesday that their findings were replicated at two other glacial lakes in the Swiss Alps.
But another lake that was not fed by glaciers did not show any increase in the compounds.
The authors said that that it was the first time that glaciers were demonstrated to be a secondary source of such pollution.
Production and use of POPs was banned or restricted under an international treaty in 2001, although several major industrialised nations such as the United States had started to outlaw them in preceding decades.
They are regarded as very durable and carcinogenic, and in some instances can be absorbed through the skin.
Their release in an Alpine setting could lead to "short but intense pulses" of pollution in spring and summer, the scientists concluded.
That could affect drinking water in Alpine huts, the food chain through fish from nearby lakes, irrigation facilities and even artificial snow on ski slopes.Swiss researchers have found that Alpine glaciers melting under the impact of climate... more
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There is no disputing that something is responsible for the acute rise in Type 2 diabetes, especially in children in the last decade. I don't think it is just what they may be eating, it is the poisons in what they are eating.
Excerpt:
Eat right and exercise, conventional wisdom has it, if you want to avoid joining the diabetes epidemic.
But a new study adds some muscle to a growing body of research suggesting those steps, although beneficial, might not be enough for people exposed to chemicals in the environment.
The scientists linked diabetes and people's body burdens of DDE, a chemical produced as the body breaks down the pesticide DDT, banned in the United States more than 35 years ago.
"Even though we haven't used DDT in decades, its metabolites are still detected in almost everyone in the country," said lead researcher Mary Turyk, an epidemiologist at the University of Illinois-Chicago's School of Public Health.
Since the early 1990s, researchers have monitored a group of Great Lakes charter boat captains, recreational fishermen and others to learn about the health effects of eating fish tainted with persistent organic pollutants - chemicals that remain in the environment for decades and grow more concentrated as they move up food chains.
For the new study, blood samples from the Great Lakes group showed "consistent, dose-related associations of DDE" with diabetes, the researchers wrote in the July issue of Environmental Health Perspectives.
Among 471 adults, including 36 with diabetes, there was no link to the disease based on the amount of fish consumed or exposure to other pollutants. But the higher the concentration of DDE in the blood, the more likely they were to develop diabetes.
Article continues: http://www.organicconsumers.org/articles/article_18633.cfmThere is no disputing that something is responsible for the acute rise in Type 2... more
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Nine persistent organic pollutants (POPs) were listed today under the Stockholm Convention. Over 160 Governments have just concluded a one-week conference with practical decisions that will strengthen a global effort to eradicate some of the most toxic chemicals known to humankind.
The Conference of the Parties (COP) has marked a historic week for the Stockholm Convention. For the first time, the Convention was amended to include nine new chemicals. Many of these are still widely used today as pesticides, flame retardants and in a number of other commercial uses.
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A landmark decision was also reached on the endorsement of the DDT global partnership. While DDT is targeted for eventual elimination, the Convention recognizes that some countries will continue to use this pesticide to protect their citizens from malaria and other diseases.
The PCB Elimination Network was also endorsed. Countries have now strengthened efforts to phase out polychlorinated biphenyls or PCBs through a cooperative framework to support countries in the environmentally sound management and disposal of these harmful substances. The Network will be tasked with establishing key data and evaluating whether the use of PCBs is indeed declining.
The Conference also reviewed the process for evaluating the Convention's effectiveness in reducing POPs over time. A global monitoring programme building on various national and regional monitoring systems will produce a worldwide picture of trends in the quantity and types of POPs in the environment and in the human body.
The message of the Conference is clear: without 'Meeting the Challenges of a POPs-free Future', the chemical footprint represented by these toxic substances will remain and the global effort to minimize their impact on human health and the environment will fail. In a big step forward, Governments worldwide have united this week under the Stockholm Convention to push chemicals issues up to the top of the global agenda.Nine persistent organic pollutants (POPs) were listed today under the Stockholm... more
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I find it quite coincidental that diabetes has also reached epidemic proportions after the introduction of GMOS in our food source. I think it is absolutely possible that the disease can be contracted from the chemicals in our food and the toxins in our environment. I think much of the health ills we suffer are environmental in nature. This is why I cannot understand why the environment is not ever linked to a healthcare plan in this country. If you tackle environmental pollution and toxins you obviously will have a positive effect on health.
From the article:
ON 10 July 1976, a reactor at a chemical plant near the small town of Seveso in northern Italy exploded, sending a toxic cloud drifting into the summer sky. Around 18 square kilometres of land was contaminated with TCDD, a member of the notorious class of industrial chemicals known as dioxins.
The immediate after-effects were relatively mild: 15 children landed in hospital with skin inflammation and around 3300 small animals were killed. Today, however, the accident casts a long shadow over the people of Seveso, who are suffering increased numbers of premature deaths from cancer, cardiovascular disease and, perhaps surprisingly, diabetes (American Journal of Epidemiology, vol 167, p 847).
To some diabetes researchers, Seveso serves as a warning to us all. Ask why diabetes is epidemic in the 21st century and most people will point the finger at bad diet, laziness and obesity. According to a small but growing group of scientists, though, the real culprit is a family of toxic chemicals known as persistent organic pollutants, or POPs. If these researchers are right, POPs - which include some of the most reviled chemicals ever created, including dioxins, DDT and PCBs - may be key players in the web of events that lead people to develop the disease.
The claim has yet to attract widespread attention from mainstream diabetes research. Even its champions were initially surprised by it. "I had never even heard of POPs until 2005," says Duk-Hee Lee, an epidemiologist at Kyungpook National University in Daegu, Korea, who led the work. Lee and her co-workers are now convinced, albeit reluctantly, that they are onto something. "The hypothesis is one that I wish were not true," says her colleague David Jacobs of the University of Minnesota, Minneapolis.
Diabetes, and particularly its commonest form, type 2 (see "Diabetes basics"), is practically everyone's business. The World Health Organization estimates that it already affects 180 million people worldwide, with the number predicted to more than double by 2030. Last year the epidemic cost $174 billion in the US alone, according to the American Diabetes Association.
The standard explanation for type 2 diabetes is that it is a "lifestyle disease" caused by laziness and gluttony. For at least a decade, however, epidemiologists have known that people briefly exposed to high concentrations of POPs face a modest increase in their risk of developing diabetes later in life. Those affected include the people of Seveso and US veterans who were exposed to dioxin-contaminated Agent Orange during the Vietnam war.
Two years ago, Lee, Jacobs and others decided to see whether everyday exposure to POPs is also linked to diabetes. To their surprise and horror, they found that it is.
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Taking into account factors such as weight, age, waist circumference and ethnic group, Lee calculated that in people with the highest combined levels of all six POPs the rate of diabetes was a massive 38 times greater than in those with the lowest levels (Diabetes Care, vol 29, p 1638). "The people who disagree with us will say it's all noise," says Jacobs, "but it's pretty hard to get odds ratios of 38 with noise."I find it quite coincidental that diabetes has also reached epidemic proportions after... more
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