~dGossip ~tLiving near traffic pollution tied to heart deaths ~w2010-07-27 According to the results from a recent study, middle-aged and older adults who live near high-traffic roads may have a heightened risk of dying from heart disease -- but the odds seem to go down if they move to a less-travelled neighbourhood. Although according to the researchers, the findings did not prove that traffic pollution is the reason for the excess heart disease deaths. However, they do add to evidence tying vehicle-produced pollutants to the risk of dying from heart problems. In May, the American Heart Association (AHA) released a report stating that recent studies have "substantially strengthened" the evidence that air pollution from traffic, industry and power generation is a risk factor for heart attack, stroke and deaths from cardiovascular causes. The evidence most strongly points to particles known as fine particulate matter, which is produced from burning gasoline and other fossil fuels. The AHA recommends that people with established heart disease and other at-risk individuals - including the elderly and people with risk factors for heart disease, like diabetes and high blood pressure -- try to limit their exposure to congested roadways and spend less time outside on days when air quality is poorer. During the new study, researcher Wen Qi Gan and colleagues at the University of British Columbia analysed data on more than 450,000 Vancouver-area residents between the ages of 45 and 85. They detected that over nine years, residents who consistently lived within roughly 500 feet of a highway or within 165 feet of a major road were more likely to die of heart disease than those who lived farther from high-traffic roadways. In addition, the researchers discovered "two new twists" to what's been known about the relationship between traffic and heart disease deaths, explained senior researcher Dr. Michael Brauer, a professor of environmental health at the university. That is, the risk of heart disease death declined among residents who moved away from high-traffic roads during the study period, while it increased among those who moved closer to congested roads. "It's sort of like what we see with smoking cessation," Brauer said. "The associated disease risks are lower in former smokers," compared with persistent smokers. The results are based on 450,283 middle-aged and older adults with no known heart disease at the outset. Approximately 53,000 persistently lived within 500 feet of a highway or 165 feet of a major road over the nine-year study. In total, 607 -- or just over 1 percent -- died of heart disease during that period; that compared with 0.7 percent of the more than 328,000 people who persistently lived farther from traffic. The researchers were able to account for a number of other factors that could explain any connection between living near major roads and having a higher risk of dying from heart disease -- including residents' age, neighbourhood income levels and any diagnoses of diabetes or major lung disease. The researchers found that living near a highway or major road was still linked to a 29 percent higher risk of heart disease death, versus living farther away. Among people who either moved away from or closer to a major road, the risk of heart disease death was also somewhat elevated -- but lower when compared with residents who persistently lived near busy roads. In addition, the researchers used air pollution data to show that people living close to highways and major roads would have been exposed to higher levels of particulate matter, nitrogen dioxide and other traffic-related pollutants. The findings do not prove that air pollution was the reason for the higher risks. Brauer said that traffic noise, for example, might be involved. Furthermore, the researchers had no information on certain key factors in heart disease risk, including people's smoking habits and weight. However, a body of research has now linked air pollution exposure to the risk of heart disease death, Brauer pointed out. He also added that the evidence suggests that traffic pollution may be a particular risk. A "big question," Brauer said, is whether exposure to air pollution is linked to the initial development of heart disease -- or whether its association with heart disease death reflects an effect mainly on people with existing heart problems. Researchers believe that air pollutants may trigger heart attacks, strokes or other cardiovascular "events" in vulnerable people by causing inflammation in the blood vessels and irritating the nerves of the lungs. Brauer suggested that people view traffic pollution as one of the range of factors that may influence their heart disease risk -- which includes exercise and diet habits, smoking and the presence of any health conditions that contribute to heart disease, like diabetes, high blood pressure and high cholesterol. Living near major roads does not mean a person is destined for heart disease. Brauer noted, living in a low-traffic area does not mean a person can slack on following a healthy lifestyle. Reuters Health, 15 July 2010 a href="http://www.reuters.com/news/health">http://www.reuters.com/news /health</a> ~dGossip ~tBADGE, made from BPA, reacts with food ~w2010-07-27 A new research report has suggested that leftover residues of a compound made from bisphenol A (BPA) for use in food can linings reacts with sugars, proteins and other parts of food to form new molecules. According to the new study published in the Journal of Agricultural and Food Chemistry, a main component of food can linings forms new chemicals when it reacts with different parts of food. BADGE, which is short for bisphenol A diglycidyl ether, is produced from bisphenol A and is a building block of certain types of resins that coat food and drink cans. Like its parent compound, BADGE has endocrine disrupting properties. The researchers from The Netherlands and Great Britain found that BADGE residue left over from manufacturing of the can coating can react with sugars, proteins and other small molecules – for example ethanol in beer. The findings demonstrate how critical it is to understand the extent of chemical migration from resin linings into the can's contents and what happens to the compounds once they interact with the food and beverage. This is important because of the implications for food safety. The European Union bases its regulations for how much BADGE can migrate from food primarily on the reaction between BADGE and water. However, according to the findings from the latest study, BADGE-water reaction only accounted for as much as 26 percent of the "disappearing" BADGE the researchers added to samples of canned tuna, apple puree and beer. Some of the remaining BADGE could be detected as BADGE-glucose and BADGE-amino acid reaction products. Even when the additional BADGE products were considered, it was still not possible to account for all of the BADGE added to the food. The researchers believe that BADGE can form products with larger, high-molecular-weight carbohydrates, fibres and proteins that would be difficult to detect directly with the methods they used. This was the case for proteins. When the researcher mixed BADGE with insulin, a large protein, the BADGE was effectively invisible. However, when they broke down the protein into its component parts, then the BADGE products could be detected. Although large molecules like the insulin-BADGE product would probably be too large to be absorbed by the body at first, it is possible that after they break down into smaller molecules in the stomach, then exposure to BADGE would be likely. The BPA-like chemical backbone of BADGE was not changed by reactions with food molecules. During this study, the researchers did not investigate whether the structural similarity of these products to BADGE and BPA might lead to similar harmful effects attributed to BPA or if the BADGE products might be related to levels of BPA that have been detected in most of the U.S. population. For the study, BADGE was added to two types of canned food – tuna in sunflower oil and apple puree – and three drinks – an ale, a stout, and a lager. Spiked and nonspiked controls were recanned, homogenised and then analysed three weeks later using liquid chromatography. Environmental Health News, 19 July 2010 <ahref="http://www.environmentalhealthnews.org/">http://www.environme ntalhealthnews.org/</a> ~dGossip ~tNational Oceanic and Atmospheric Administration Finds PM and Black Carbon in Air near Gulf Spill ~w2010-07-27 National Oceanic and Atmospheric Administration (NOAA) scientists said their data on air quality measurements taken in June in the vicinity of the Deepwater Horizon/BP oil spill area are consistent with those of the U.S. Environmental Protection Agency and the Occupational Safety & Healthy Administration. The new NOAA report provides a summary of the levels of nearly 100 air pollutants measured with sophisticated air sampling instruments onboard a WP-3D research aircraft. During the analysis, the researchers detected common air pollutants including ozone, nitrogen oxides and carbon monoxide, in amounts typical of urban areas in U.S. cities. However, 15 to 70 kilometres downwind from the oil spill, concentrations of certain hydrocarbons were much higher than found in typical polluted air. Particulate matter downwind of the oil slick was comparable to concentrations in moderately polluted urban air, but the particles were almost entirely organic material, as opposed to those typically found in urban particulate matter. In addition, the researchers measured large amounts of black carbon in smoke from a controlled burn of crude oil on the water. “Data from the NOAA flights are providing an important detailed and independent set of air quality data to assess air quality risks of workers at sea and the public ashore,” said A. R. Ravishankara, director of the Chemical Sciences Division of NOAA’s Earth System Research Laboratory, who led the study. NOAA scientists measured the air pollutants in four areas, including in the immediate vicinity of the spill, downwind from the spill, and along the Mississippi, Alabama and Florida coastlines. In addition, they measured “background” air in an area far from the spill to serve as a control sample. In analysing the levels of the pollutants, scientists compared them to typical concentrations of a polluted U.S. urban area. The near-shore measurements, 30 to 40 kilometres from shore, demonstrated pollution concentrations generally lower than those typically found in urban areas. The background air was relatively free of pollution from the oil spill. The report offers a highly detailed snapshot of the concentrations of hydrocarbons and other organic chemicals, particulate matter, ozone, carbon monoxide, nitrogen dioxide, peroxyacetyl nitrate and a host of other air pollutants in the Gulf in early June. Measurements were taken from as low as 60 meters above sea level and up to 1,000 meters above sea level, with most flight tracks being about 150 meters above the Gulf. Environmental Protection News, 22 July 2010 <a href="http://www.eponline.com">http://www.eponline.com</a> ~dGossip ~tFlame retardants in house dust match residents' blood levels ~w2010-07-27 A new study has reported that people living in houses with higher levels of flame retardant chemicals in the dust have themselves higher levels of the chemicals in their blood. This finding implicates dust as a major exposure source for the compounds. The mystery of why some people have higher levels of certain flame retardants in their bodies than others may hinge on simple house dust, according to the new study by a team of U.S. researchers. Previous research indicates that dust and food are major sources of exposure to PBDE chemicals yet questions remained regarding the importance of dust as a source. In the new study, the role of dust is clarified because it is the first research to compare levels of flame retardants in house dust with levels in the people who live in the same house. The researchers report that while some foods do harbour PBDEs, eating and breathing dust seems to be the main source of exposure in the United States. Dust, then, may provide an easy and accurate way to predict exposures in the people who live in the home, the researchers explain. This is in contrast to some European countries. PBDE levels are remarkably lower in dust samples collected in Europe compared to the United States, possibly because many PBDEs were banned there years ago. For example, in Belgium and Germany, no associations are found between PBDE levels in dust and in people's blood. Furthermore, levels vary across the United States. The highest levels of PBDEs are measured in Californians. The state has the strictest fire safety standards in the nation, and therefore, flame retardant use is high. Many consumer products contain PBDEs. During fires, the chemicals slow down burning of the electronics, carpeting, textiles, mattresses and upholstered foam furniture that contain them. In the United States, several PBDEs have been phased out of use because of concerns for the toxic and hormonal effects of these chemicals. However, older products such as carpets and furniture that contain these types continue to release them as they age. In addition, products with these chemicals can still be imported and sold. In rodents, certain PBDEs can affect brain development and thyroid hormone levels as well as having endocrine disruptor activities. That is, they can act like or prevent the normal action of hormones in those animals. Additional studies in humans suggest that higher levels of some PBDEs in the body can lead to altered hormone levels. During the new study, the researchers collected used vacuum cleaner bags from 50 households in Massachusetts and examined the contents for the presence of over 30 PBDEs. At the same time, blood samples from 12 adult couples were collected and tested for several of the PBDE types found in the majority of the house dust samples. The levels and types measured show that PBDEs are a large component of indoor dust. Total PBDE concentrations averaged 4,742 nanograms per gram (ng/g) and ranged from 980 to 44,546 ng/g. Of those measured, six were not detected in any house, three were found in a small number of houses – less than 30 percent – and the rest were found in the majority of the dust samples. Thirteen PBDEs were detected in every house sampled. Three of those – BDE 47, 99 and 100 – had related levels in dust and in blood. That is, houses with high levels of these chemicals in dust samples were likely to have occupants with high levels of the chemicals in their blood. Gender had a similar strong association; men with high levels in their blood were likely to live with women who also had high levels in their blood. Environmental Health News, 23 July 2010 <ahref="http://www.environmentalhealthnews.org/">http://www.environme ntalhealthnews.org/</a> ~dGossip ~tHeart risk factors less common in fish lovers ~w2010-07-27 The results from a new study have suggested that middle-aged and older men who eat fish every day are less likely than infrequent fish eaters to develop a collection of risk factors for heart disease, diabetes and stroke. At this stage it is unclear whether it is the fishy diet itself that is contributing to the health benefits. But, the researchers say, the results are in line with studies showing that omega-3 fatty acids -- found most abundantly in oily fish like salmon, mackerel and albacore tuna -- may have heart benefits. Clinical trials have demonstrated that omega-3s can lower triglycerides (a type of blood fat), and a prescription medication containing the fats -- sold as Lovaza -- is sometimes used to treat very high triglyceride levels. In addition, the researchers have suggested that fish oil supplements can help lower blood pressure and may reduce the risk of death among people with established heart disease, according to the National Institutes of Health. During the new study, of 3,500 Korean adults ages 40 to 69, the researchers found that men who had a serving of fish each day were 57 percent less likely than those who dined on fish less than once per week to develop metabolic syndrome over three years. Metabolic syndrome refers to a collection of risk factors for diabetes, heart disease and stroke -- including abdominal obesity, high blood pressure, high blood sugar, low HDL cholesterol and high triglycerides. The syndrome is typically diagnosed when a person has three or more of those traits, and the National Health and Nutrition Examination Survey, a major study, found that it can double the risk of heart attack and stroke. Previous studies have detected an association between higher fish intake and a lower risk of some individual components of metabolic syndrome. However, the current study is the first to demonstrate an association with the collection of risk factors, according to the researchers, led by Dr. Inkyung Baik of Kookmin University in Seoul. The researchers found that of 232 men who said they ate fish every day at the study's outset, 29 -- or about 12 percent -- developed metabolic syndrome over the next three years. Of the 190 men who said they ate fish less than weekly, 16 percent developed metabolic syndrome. When Baik's team considered other factors -- including the men's income and education, body weight and lifestyle habits such as smoking and exercise -- daily fish consumption was linked to a 57 percent lower risk of metabolic syndrome versus less-than-weekly consumption. However, there was no such association seen among women. The reason for the gender discrepancy is not clear. The researchers speculate that, as a group, women may not have gotten enough omega-3 fatty acids from fish to show a reduction in the risk of metabolic syndrome. Men in the top 10 percent for omega-3 intake from fish typically got 786 milligrams (mg) per day, while their female counterparts got 563 mg. In addition, men in that top omega-3 group showed a lower risk of metabolic syndrome than those in the bottom 10 percent -- which, according to Baik's team, supports the theory that it is the fats that explain the connection between fish and the risk of metabolic syndrome. However, this type of study cannot by itself prove cause-and-effect. "Our findings need to be confirmed by other investigators," Dr. Chol Shin, one of the researchers on the study and a professor at Korea University Ansan Hospital, said. And in general, it is not yet clear what the optimal daily intake of omega-3 fatty acids might be, Shin noted. In the U.S., there is no recommended daily allowance set for EPA and DHA, the two major omega-3 fatty acids, writes registered dietitian Gretchen K. Vannice, in an editorial published with the study. However, she adds, the American Dietetic Association and other groups have suggested a daily allowance of anywhere from 250 to 500 mg of EPA and DHA, based on the overall body of research into omega-3s and heart health. Two servings of fatty fish per week would be enough to achieve those levels, Vannice notes. Furthermore, that fits in with the current advice from the American Heart Association that adults strive to eat two servings of fish, preferably fatty varieties, each week. However, even if eating fish regularly does help reduce the risk of metabolic syndrome or its components, it would be only one of many factors involved. A healthy weight, not smoking, regular exercise, and a balanced diet rich in fruits, vegetables, high-fibre foods and "good" unsaturated fats are all considered important. Reuters Health, 20 July 2010 a href="http://www.reuters.com">http://www.reuters.com</a> ~dGossip ~tSmog Might Trigger Cell Death in the Heart, Study Finds ~w2010-07-27 At the recent American Heart Association's Basic Cardiovascular Sciences 2010 Scientific Sessions -- Technological and Conceptual Advances in Cardiovascular Disease, researchers reported that an earlier study in rats provided the first direct indication that a major component of smog might trigger cell death in the heart. The study found that exposure to ground-level ozone over several weeks increased the activity of a substance that triggers cell death in the heart. Ozone (O3) is a highly reactive gas made up of three oxygen molecules. In the upper atmosphere, it protects Earth from the sun's radiation. However, O3 becomes a major component of smog when it forms near the ground through reactions between sunlight, nitrogen oxides and hydrocarbons from fossil fuels and industrial processes. "Several epidemiological studies have linked air pollution to the development of cardiovascular disease, but air pollution contains hundreds of chemicals and those studies were unable to separate out the effects of individual components," said Rajat Sethi, Ph.D., an assistant professor in the Department of Pharmaceutical Sciences at the Texas A&M Health Science Centre Irma Lerma Rangel College of Pharmacy in Kingsville, Texas. "Our study looked for direct evidence of the role of ozone alone in cardiac dysfunction by creating a controlled environment." During the study, the researchers tested four groups of 10 rats living in clear plastic-glass boxes. The first two groups were exposed for eight hours a day to 0.8 parts per million (ppm) of O3 for either 28 or 56 consecutive days. The other two groups were exposed to 28 days or 56 days of clean, filtered air for eight hours per day. After the eight hours of testing, all the rats experienced 16 hours of clean air overnight. The results demonstrated that the hearts of the O3-exposed rats had increased levels of tumour necrosis factor-alpha (TNF α), an indication of inflammation compared to hearts of the control rats. Increased TNF α levels have been linked to a drop in levels of a heart-protective protein called Caveolin-1 (Cav1). Scientists believe Cav1 protects the heart by binding to a chemical called p38MAPK alpha (p38MAPK α), which is known to be a cell death signalling chemical, Sethi said. The researchers found that Cav1 levels decreased in the hearts of rats exposed to O3 compared to the hearts of control rats who breathed filtered air. "We believe the decreased levels of Cav1 make more unbound p38MAPK α available for telling the heart cells to die. That link between Cav1 and O3 has never been shown in the heart," Sethi said. Science Daily, 22 July 2010 <a href="http://www.sciencedaily.com">http://www.sciencedaily.com</a> ~dGossip ~tZinc sprays dull sense of smell in some users ~w2010-07-27 New research has concluded that homeopathic zinc nasal sprays don't fight colds, and they probably cause some people to lose their sense of smell. "Increased Food and Drug Administration oversight of homeopathic medications is needed to monitor the safety of these popular remedies," Drs. Terence M. Davidson and Wendy Smith of the University of California, San Diego, and the Veterans Affairs San Diego Health System write in the July issue of the Archives of Otolaryngology -- Head and Neck Surgery. Homeopathic remedies contain tiny amounts of certain substances mixed with inactive ingredients. While the FDA requires people dispensing homeopathic drugs for "serious disease conditions" to be licensed, Davidson and Smith note, regulation of over-the-counter products is virtually nonexistent. While over-the-counter zinc gluconate sprays remain a popular cold remedy, a number of well-designed studies have shown that the sprays don't work, the researchers point out. There's also growing evidence that zinc nasal sprays could dull people's sense of smell, or even eliminate it, possibly permanently, they add. During the new study, the researchers investigated whether zinc sprays could actually be causing users to lose their sense of smell by examining 25 people who lost their sense of smell soon after using zinc gluconate gel. All had sought care at the university's Nasal Dysfunction Clinic. In addition, they reviewed the medical literature on the relationship between zinc use and olfactory problems. The researchers used a set of nine requirements known as the Bradford Hill Criteria to determine whether zinc caused the patients' olfactory problems. Researchers developed the criteria in 1965 so they could test whether tobacco smoking causes lung cancer without having to perform a large - and unethical - study in which they assigned some people to smoke. The seven criteria require that several people in different parts of the world see the same relationship, which the effect occurs soon after the potential cause, and other findings. The researchers discovered that the zinc-olfaction relationship fulfilled all nine criteria. For example, people report a loss of sense of smell within minutes to hours after using the spray; also, the relationship between zinc use and loss of sense of smell has been reported by several independent groups of researchers. "Based on our analysis, it appears evident that intranasal zinc can and does cause anosmia," the clinical term for loss of sense of smell, the researchers say. Right now, they add, homeopathic remedies aren't required to follow FDA rules on expiration dating or laboratory testing to confirm that they actually contain the active ingredients they claim, at the stated strength. "Protecting our patients from the potential risks of intranasal zinc medications and other homeopathic drugs, especially ones with limited therapeutic benefit, should be a high priority of the FDA," Davidson and Smith conclude. Reuters Health, 21 July 2010 a href="http://www.reuters.com/news/health">http://www.reuters.com/news /health</a> ~dGossip ~tGulf Oil Dispersants Unlikely to Be Endocrine Disruptors and Have Relatively Low Cell Toxicity, Tests Find ~w2010-07-27 Government researchers have reported that eight of the most commonly used oil dispersants used to fight oil spills, such as the massive episode in the Gulf of Mexico, appear unlikely to act as endocrine disruptors -- hormone-like substances that can interfere with reproduction, development, and other biological processes. In addition, the tested dispersants had a relatively low potential for cytotoxicity (cell death), with JD-2000 and SAF-RON GOLD showing the least potential. The researchers were from the U. S. Environmental Protection Agency and the National Institutes of Health Chemical Genomics Centre. The study was published in the journal Environmental Science & Technology. Richard Judson and colleagues note that more than 1.5 million gallons of dispersants have been used so far in the Deepwater Horizon spill. These detergent-like chemicals break up oil slicks into small drops. Scientists are concerned that some dispersants contain ingredients that turn into endocrine disruptors in the environment, and could harm marine mammals, fish, and humans. But only limited toxicity testing data is available on currently-used dispersants, and this is only results from the first round of EPA dispersant testing, they state. With an urgent need for such information in the Deepwater Horizon spill, the scientists applied a rapid screening method using mammalian cells to determine the eight dispersants' potential to act as endocrine disruptors and relative toxicity to living cells. The dispersants included a type widely being used to treat the Gulf oil spill. None of the substances showed significant endocrine disruption activity and cytotoxicity was not seen until dispersants were tested at concentrations above 10 parts per million, the scientists said. However, they note that "there are other routes by which chemicals can cause endocrine disruption, as well as other types of toxicity that have not been tested for here." Science Daily, 22 July 2010 <a href="http://www.sciencedaily.com">http://www.sciencedaily.com</a> ~dGossip ~tChemicals higher, thyroid hormone lower in pregnant women near ewaste recycling ~w2010-07-27 Yet another study has raises concerns regarding e-waste recycling and its effects on human health following a new report, which found that pregnant women in China who live nearer the facilities have higher levels of toxic chemicals and depressed levels of thyroid hormones. Pregnant women who live in areas close to electronic waste dismantling sites have higher exposures to persistent organic pollutants and depressed thyroid hormone levels than those who live farther away from the facilities, a new study that compares women in two regions of China, has found. Despite the fact that they have no interactions with the e-waste facility, the recycling activities affect the women living adjacent to the sites. This study raises concerns about e-waste practices and health effects on both the mothers and the developing foetuses. This is the first study to evaluate the levels of these three groups of pollutants in people who live near e-waste recycling sites and to determine their effect on thyroid hormone levels. The results of this study mostly agree with findings from the few prior studies that have also looked at the effects of the chemical groups – either alone or in pairs – on thyroid hormones. PCBs and PBDEs are widely-used chemicals found in electronic products. PCDDs/Fs are typically formed when the electronic products containing these chemicals burn – as sometimes happens during their gutting and recycling. These chemicals have been either banned or phased out from use due to persistence, bioaccumulation and toxicity concerns. Yet, the compounds are still present in residential areas and in consumer products. Electronic waste recycling – including burning, acid leaching and dismantling – can release the pollutants into the air, water and soil where people can be exposed to high levels. All of the chemicals measured affect thyroid regulation in animal exposure studies. Several of these studies document significant associations between exposure to the contaminants and depression of thyroid hormone levels in both children and adults. Steady thyroid hormone levels are critical to the developing foetus, particularly for physical and mental development. Low thyroid hormone levels can cause delays and brain and nervous system problems. During the study, the researchers examined 50 pregnant women who lived in two different regions in southeast China for at least five years. One region is a well-known e-waste recycling area (zone A), in which recycling has been going on for more than 25 years. The second region represents a control reference site (zone B) and is located more than 250 kilometres away from the first region. Researchers measured the levels of about 17 chlorinated dioxins (i.e. PCDDs and PCDFs), six polychlorinated biphenyls (PCBs) and six polybrominated diphenyl ethers (PBDEs) in cord blood collected during delivery. Thyroid hormone levels – T3, thyroxine (T4) and thyroid stimulating hormone (TSH) – were measured in the women’s blood samples taken during the sixteenth week of pregnancy. The results demonstrated that in general, women living near the recycling facilities had higher body burdens – and thus, higher exposures – to all three chemical classes than the women who lived farther away. Median concentrations of PCDDs/Fs, PCBs and PBDEs in cord blood collected from those who live close were 3 times, 5.4 times and 1.4 times higher, respectively, than the levels measured in cord blood collected from women who lived farther away. Furthermore, total thyroxine and thyroid stimulating hormone (TSH) were significantly lower in women nearer the recycling activities. The researchers found that as PCDDs/Fs and PCBs levels increased, levels of T4 decreased. This association was statistically significant. The researchers concluded that the findings from the latest study suggest that further research into human health effects of both employees in e-waste sites and for people living in cities with e-waste facilities from exposure to chemicals released during e-waste practices is warranted. Environmental Health News, 20 July 2010 <ahref="http://www.environmentalhealthnews.org/">http://www.environme ntalhealthnews.org/</a> ~dGossip ~tRecreational Pool Disinfectants Linked to Health Problems ~w2010-07-27 Splashing around in a swimming pool on a hot summer day may not be as safe as you think. According to the finds from a new study by researches at the University of Illinois, the application of disinfectants in recreational pools is linked to previously published adverse health outcomes such as asthma and bladder cancer. Each year, 339 million visits take place at pools and water parks across the United States. Not only is swimming fun, but it's also the second most popular form of exercise in the country. Because of this, disinfection of recreational pools is critical to prevent outbreaks of infectious disease. However, Michael Plewa, U of I professor of genetics, said negative outcomes can occur when disinfection byproducts form reactions with organic matter in pool water. Pool water represents extreme cases of disinfection that differ from the disinfection of drinking water as pools are continuously exposed to disinfectants. "All sources of water possess organic matter that comes from decaying leaves, microbes and other dead life forms," Plewa said. "In addition to organic matter and disinfectants, pool waters contain sweat, hair, skin, urine, and consumer products such as cosmetics and sunscreens from swimmers." These consumer products are often nitrogen-rich, causing concern that they may contribute to the generation of nitrogenous disinfection by-products, Plewa added. When mixed with disinfectants, these products may become chemically modified and converted into more toxic agents. These disinfection byproducts can mutate genes, induce birth defects, accelerate the aging process, cause respiratory ailments, and even induce cancer after long-term exposures. In this study, collections from public pools and a control sample of tap water were evaluated to identify recreational water conditions that could be harmful to your health. During the new study, a systematic mammalian cell genotoxicity analysis was used to compare the water samples. Plewa said this sensitive DNA technology examined genomic damage in mammalian cells, allowing researchers to investigate damage at the level of each nucleus within each cell. The study compared different disinfection methods and environmental conditions. The findings proved that all disinfected pool samples exhibited more genomic DNA damage than the source tap water, Plewa said. "Care should be taken in selecting disinfectants to treat recreational pool water," Plewa advised. "The data suggest that brominating agents should be avoided as disinfectants of recreational pool water. The best method to treat pool waters is a combination of UV treatment with chlorine as compared to chlorination alone." Plewa recommends that organic carbon be removed prior to disinfection when the pool water is being recycled. Furthermore, swimmers can help reduce the genotoxicity of pool water by showering before entering the water. Pool owners should also remind patrons about the potential harm caused by urinating in a pool. These simple steps can greatly reduce the precursors of toxic disinfection by-products, Plewa said. Science Daily, 22 July 2010 <a href="http://www.sciencedaily.com">http://www.sciencedaily.com</a> ~dGossip ~tNew membrane makes fresh water from sea and sewage feasible ~w2010-07-27 A special membrane turns salty sea water into fresh water, paving the way for large-scale desalination that would provide desperately needed drinking water. The technology, developed by researchers at Yale University, can clean and purify water from oceans, salty ground water or sewage water with far less energy input than currently is required to do a similar job. The membrane may be a big step forward in reaching the goal of reliable and affordable sources of fresh water. Finding sustainable sources of clean drinking water is a major global challenge, especially in most of the developing world. The need is apparent in both urban areas, due to growing population and demand, and rural regions, where sometimes scarce water supplies are quickly drying up. As fresh water becomes more scarce, desalination and filtering will be increasingly necessary to satisfy the world’s unquenchable thirst for this precious commodity. Yet, neither of the existing desalination technologies – distilling sea water vapours by boiling then collecting the water vapours or reverse osmosis where water is pushed through membranes to filter the salt – are feasible on a large scale. Both require high amounts of energy to either boil the water or create pressure. A newer approach does not require external heat or pressure but lacks an adequate membrane to filter the water. The technique uses a mixture of dissolved carbon dioxide and ammonia gas in water on one side and salty or dirty water on the other side of the membrane. The gas/water mixture draws the clean water through the membrane and leaves the salt and dirt on the other side. A small amount of heat is then applied to drive off the carbon dioxide and ammonia, leaving just pure, fresh water. However, no current membranes can stand up to the ammonia. Now, researchers report that they have developed one – a thin-film composite forward osmosis membrane. They describe the new development in the journal Environmental Science and Technology. The membrane is permeable enough to allow water to flow freely through it but resistant enough to keep the ammonia and chemicals in sewage from passing through it. This landmark development is a beginning. More research is required to bring down the costs of the membranes and make this technology accessible in all parts of the world. Environmental Health News, 20 July 2010 <ahref="http://www.environmentalhealthnews.org/">http://www.environme ntalhealthnews.org/</a> ~dGossip ~tKey Finding: Many Pathogenic Fungi Use the Same Entrance to Invade Host Cells ~w2010-07-27 In a new study, researchers have discovered that many deadly pathogens use the same protein to gain access to the cells of a potential host. The new findings could have implications for blocking infections by agents ranging from wheat rust to malaria. Pathogenic fungi, such as flax rust and soybean rust, and similar pathogens known as oomycetes, such as the organism behind the Irish potato famine and sudden oak death, make similar proteins to disarm their hosts' defences. But to work, these effector proteins need to first make their way inside of a cell. Up until now, researchers did not know, in the first place, how these compounds were able to break in. The new study, published in the journal Cell, describes how these blights do it. To infect a plant, pathogenic fungi and oomycetes make a protein called RXLR—a type of effector protein—which enters plant host cells and blocks the plant's defences. However, the new research shows that both of these types of organisms are able to insert their effector proteins inside the cell by binding with a single type of lipid on the host cell's surface. This union allows the effector protein to be carried into the cell through the cell wall, where it can start doing damage. "Even though they're very different, they're using a similar mode of entry," says Shiv Kale, a National Science Foundation graduate research fellow at Virginia Tech's Virginia Bioinformatics Institute and lead author of the new paper, of the various plant pathogens. The "key" that the pathogens use to get into host cells is a lipid known as phosphatidylinositol-3-phosphate (or PI-3-P). That such different organisms would make use of a single lipid was a surprise to Kale and his colleagues. And although PI-3-P had been described before, "that lipid is predominantly on the inside of the cell," Kale says, so finding it on the exterior surface of the cells was "really exciting." Even though the universality of the lipid use was unexpected, "it makes sense from an evolutionary standpoint," Kale explains. If the single key could give pathogens access to a multitude of hosts, the talent would be worth keeping around, leading Kale to conclude that the pathogens' mode of entry is probably "ancient and highly conserved." The single common technique for entry could be salutary for humans and the crops we depend on, though, as researchers in agriculture and medicine strive to find the best ways to block fungal and oomycete infections. "The finding is no doubt a breakthrough in host–pathogen interaction," Takao Kasuga and Lynn Epstein, both of the Department of Plant Sciences at the University of California, Davis, noted in a joint e-mail. "We now know how pathogens' effector proteins are delivered into host cells." These lipid receptors were not just found on the surface of the plant cells tested by Kale and his colleagues, but on some animal cells as well—including human lung epithelial cells. Kale is hopeful that the findings might someday be put to use in new treatments that could suppress PI-3-P and block the pathogen's path. "It seems that if you can find a target for this entry mechanism, you could develop a therapeutic," he says. Such a medication might be useful to patients who have compromised immune systems and fall prey to fungal infections that healthier individuals can usually fight off, such as those with AIDS who are more susceptible to cryptococcal meningitis, a fungal infection that can attack the nervous system. However, the new data did not illuminate whether any of the host's biological processes would be interrupted if the binding capabilities of their cells' external PI-3-P were inhibited, Kale says. And not everyone is sure blocking the host's binding lipid is going to be a simple approach. The substance in question is "a ubiquitous and extremely important part of the cell membrane," Kasuga and Epstein noted. "Manipulating and blocking of effector–PI-3-P interactions without interfering with PI-3-P functions in healthy cells may be a challenge." More broadly, the findings could help to shed light on other scourges, such as malaria. Red blood cells, which malaria infects, have not been shown to have PI-3-P on their surfaces. Nevertheless, the malaria parasite Plasmodium seems to have developed a similar mechanism for entering the cells, Kale notes. Furthermore, examining various entry methods of pathogens, researchers like Kale hope to zero in on an early, possibly universal step in the infection process. Currently, scientists from various disciplines are designing new trials to start putting these findings to work in agricultural and medical realms. Kale notes that this sort of basic discovery, although minute, is just the kind of jumping-off point many basic science researchers dream of. He hopes that eventually preventive treatments will "have some benefit to humanity because of it." Scientific American, 23 July 2010 <a href="http://www.sciam.com">http://www.sciam.com</a> ~dGossip ~tBetter Sampling Needed in Wastewater Monitoring ~w2010-07-27 A new study by Australian researchers has shown that improper sampling protocols to detect pharmaceuticals, personal care products, and illicit drugs in sewage can lead researchers to misestimate the chemicals' concentrations or miss the pollutants altogether. The new study was published in the journal Environmental Science & Technology. Chemical contaminants appear and disappear over time in wastewater, so whether or not researchers detect them depends on when and how frequently scientists collect samples. Scientists want to quantify the flux of pharmaceuticals, personal care products, and illegal drugs through sewage systems to determine how much we release into the environment and to improve sewage plants treatments. However, many scientists lack the instruments that can monitor these contaminants' dynamics with sufficient time resolution, says environmental engineer Christoph Ort of the University of Queensland in Australia. In a separate study, Ort and colleagues examined 87 recent papers that studied 267 different sewer sites, and found that the authors didn't cite or heed internationally-accepted sampling practices. Researchers often collected samples too infrequently and then pooled all their samples together for analysis; in doing so, they lost all information about the dynamics of a compound over time and possibly missed pollutants. In the present study, Ort and colleagues illustrate the point by tracking a medical-imaging contrast agent at a sewage treatment plant that served 100,000 inhabitants. Based on how frequently doctors use the chemical, the investigators estimated that at most one or two people in that population would excrete the compound into the sewage system during a weekday. Then, the researchers monitored the wastewater over a fourhour time period. To ensure that they didn't miss a single toilet flush, they collected 120 samples, each consisting of two minutes of wastewater flow. When they analysed the samples by mass spectrometry, the contrast agent only showed up in 30. If they had sampled less frequently, the scientists may have missed its presence completely. Scientists often resort to improper sampling because of expense or logistical limitations, says chemist Bruce Brownawell at Stony Brook University in New York, but this study highlights its pitfalls: "It makes us vigilant about paying attention to the sampling methods." Chemical & Engineering News, 23 July 2010 <a href="http://pubs.acs.org/cen/news">http://pubs.acs.org/cen/news</a> ~dGossip ~tVitamin C helps fight cancer A new study, led by Associate Professor Margreet Vissers of the University of Otago’s Free Radical Research Group, is the first real evidence of a connection between vitamin C and tumour growth. Associate Professor Vissers says “Our results offer a promising and simple intervention to help in our fight against cancer, at the level of both prevention and cure”. The new study was published in the journal Cancer Research. The role of vitamin C in cancer treatment has been the subject of debate for many years, with many anecdotal accounts of the beneficial role of vitamin C in both the prevention and treatment of cancer. In previous studies, Associate Professor Vissers has demonstrated the vitamin’s importance in maintaining cell health and hinted at its potential for limiting diseases such as cancer. In her latest research, she investigated whether vitamin C levels were lowered in patients with endometrial tumours. The study examined whether the cancer cells had low vitamin C levels and whether this correlated with tumour aggressiveness and resistance to chemotherapy. Associate Professor Vissers and her colleagues discovered tumours were less able to accumulate vitamin C compared with normal healthy tissue, and that this related to the ability of the tumour to survive and grow. Tumours with low vitamin C levels had more of a protein called HIF-1 which allows them to thrive in conditions of stress. The findings are significant as they show, for the first time, a direct relationship between HIF-1 and vitamin C levels in tumours and suggest it would be beneficial for people with cancer cells to have more vitamin C. This could help limit the rate of tumour growth, increase the responsiveness to chemotherapy and may prevent the formation of solid tumours. Science Alert, 19 July 2010 <a href="http://www.sciencealert.com.au">http://www.sciencealert.com.au< /a> ~dGossip ~tResearchers Model Personal Pollution Exposure ~w2010-07-27 In a new study, researchers have concluded that people's diet, not their local environment, best determines their pollutant loads. Environmental toxicologists would like to better predict how much organic chemical pollution settles into our bodies, but two roadblocks stand in their way. Scientists don't know the exact emission rates of these chemicals or how quickly they biodegrade in the environment. A new study sidesteps these data gaps and finds that people's diets matter more than their local environment. Organic contaminants, such as plasticisers and pesticides, make a long, complicated trip through the environment to us. "This complexity leads to great variability in human exposure between ecosystems," says Emma Undeman, an environmental chemist at Stockholm University in Sweden. For example, even though pollution emissions in the Arctic are very low, people who live there accumulate greater levels of harmful chemicals than people living in higher-emitting temperate regions. Undeman and her colleagues wanted to find a novel way to predict this variability that overcame toxicologists' two roadblocks. They started by asking a question: If different ecosystems, such as the tropics or the Arctic, had identical emission levels and you compared people's contaminant loads in each region, how would they differ? To answer their question, the scientists combined two models: one that calculates how chemicals move in an ecosystem and one that analyses how the chemicals behave in that region's food chain. The models took into account environmental factors such as temperature and precipitation along with details about people's diet from each region. With their linked-up models, the researchers set pollution emission rates equal for all ecosystems and estimated a person's average pollutant exposure in each region. They then normalised each region's estimates to that of the temperate zone to create an exposure susceptibility index, which allowed them to rank exposures for each region. Not surprisingly, the Arctic came out on top. But the gap between the Arctic and other regions was larger than expected: A person living in the Arctic is about 520 times more susceptible to some pollutant exposures than a person eating a mixed diet in the temperate zone, the scientists estimated. Surprisingly, diet was the key factor, Undeman says. "The Arctic is a very susceptible environment because people there eat seal, which is a very good exposure vector for chemicals," she says. Seals and other marine mammals pack a high pollutant load because they live longer and feed on predatory fish that bioaccumulate contaminants. Because vegetables sit at the bottom of the food chain and amass fewer pollutants, vegans in temperate zones were the least susceptible, the researchers concluded. Frank Wania, an environmental chemist at the University of Toronto, Scarborough in Canada and a co-author of the study, says that these calculations show that policymakers can't take risk assessments for the well-studied temperate region and apply them elsewhere, because the risks vary by several orders of magnitude. Tom McKone, an environmental health scientist at the University of California, Berkeley, agrees that these susceptibility calculations could be powerful tools for policymakers: "It takes a complicated set of processes and integrates it into a single number that makes sense." Chemical & Engineering News, 22 July 2010 <a href="http://pubs.acs.org/cen/news">http://pubs.acs.org/cen/news</a>
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