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Toys, refrigerators, washing machines, socks—more and more products contain silver nanoparticles. It’s no wonder: These particles, which measure less 100 nanometers (smaller than a single HIV virus), can kill microbes on contact. But, researcher Darin Furgeson says, nanosilver can also escape into ecosystems and cause serious damage to fish embryos. Furgeson’s team published its results in the journal Small.

In one new experiment, Furgeson, a professor of pharmaceutical sciences, exposed zebrafish embryos to silver nanoparticles in a laboratory, and found that some died and others were left with dramatic mutations. “Some of the fish became extremely distorted, almost making a number nine or a comma instead of a linear fish,” he said [Scientific American]. Eyes, tails, and other body parts turned out malformed in the fish that survived.

Just how much nanosilver gets into the environment? A separate study from Environmental Science & Technology washed nine kinds of nanosilver-containing textiles, including some “anti-bacterial and anti-odor socks” that are already on the market. The researchers found that anywhere from less than 1 percent to as high as 45 percent of the silver came out in the first wash. Most of the silver was in the form of coarse particles of greater than 450 nanometers, suggesting that mechanical stress in the washing machine was responsible for most of the release [The New York Times], and that the nanoparticles might have aggregated to reach that size.

Those nanoparticles flushed out by a washing machine can end up in both fish habitats and drinking water supplies. Furgeson says his fish experiments could help show whether nanosilver is a health concern for humans, too. “Zebrafish have similar tissues and organs to us,” Furgeson said. “They don’t have lungs, but they do have a liver, kidneys and heart – though it is only two chambered – and they have a blood-brain barrier” [Scientific American].

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Image: Wiki Commons / Kristof vt

Environmental monitoring is often expensive, cumbersome, and time-intensive. Equipment that can run quick and easy tests for pollutants like pesticides in our food are almost nonexistent. However, researchers in Canada are working on a new biomonitoring technique using treated paper on a stick that can quickly identify trace amounts of pesticides in your chicken soup, or your first early morning cup of joe [Technology Review]. Could these dipsticks lead to DIY pollution monitoring one day? That may still be far off, but this technology could give researchers a reliable and cheap way to get a better picture of what pollutants—even at trace amounts—are in the environment, and how they interact with our bodies.

In the study, published in the journal Analytical Chemistry, the researchers describe a new paper-based test strip that changes color shades depending on the amount of pesticide present. In laboratory studies using food and beverage samples intentionally contaminated with common pesticides, the test strips accurately identified minute amounts of pesticides. The test strips, which produced results in less than 5 minutes, could be particularly useful in developing countries or remote areas that may lack access to expensive testing equipment and electricity, they note [R&D Magazine]. If the dipsticks pan out, restaurant customers may one day have more to complain about than a stray hair in their soup.

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Image: ACS

It seems that every day brings a new electronic gadget to the market, whether it’s a smart phone, an electronic reader, a laptop the size and weight of a magazine, or a television the size of a wall. But each advance adds to the world’s electronic waste, which is the fastest-growing component of solid waste. Much of the electronic refuse ends up in developing countries, where workers strip down the gadgets to get at the copper and other valuable metals inside, often exposing themselves to toxins in the process. Now, scientists are calling for federal regulations in the United States to stem the tide.

Although the U.S. is one the world’s largest producers of electronic waste (e-waste), it is hardly a leader in addressing this problem, given that the country has “no legally enforceable federal policies requiring comprehensive recycling of e-waste or elimination of hazardous substances from electronic products,” the researchers say [Scientific American]. Instead, e-waste policies are left to the states, not all of which have laws on the books. In the article, published in Science, the authors note that the United States has not ratified the Basel Convention, which regulates the movement of hazardous wastes across international borders and has the support of 169 of the 192 United Nations member countries [Scientific American].

Electronics can contain a host of dangerous materials, from heavy metals to toxic chemicals. Toxic e-waste shows up in forms as varied as high lead levels in the blood of children in Guiya, China, where millions of tonnes of e-waste are illegally dumped, and as fire-retardant chemicals in the eggs of California’s peregrine falcons [CBC News].

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Image: Basel Action Network. E-waste in a Nigerian dump.

Here’s one direct and obvious effect of the economic stimulus package passed in February: The toxic sites where scientists ushered in the nuclear age are getting cleaned up. In Los Alamos, New Mexico, a dump that contains refuse of the Manhattan Project and that was sealed up decades ago is finally being explored, thanks to $212 million from the American Recovery and Reinvestment Act.

But experts aren’t sure what they’ll find inside the dump. At the very least, there is probably a truck down there that was contaminated in 1945 at the Trinity test site, where the world’s first nuclear explosion seared the sky and melted the desert sand 200 miles south of here during World War II [The New York Times]. It may also contain explosive chemicals that could have become more dangerous over the years of burial.

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To zero in on air pollution, just follow the magnetic tree leaves.

That’s the conclusion of an odd new study, which determined that the microscopic metallic particles spewed out of tailpipes and smokestacks actually magnetize the nearby leaves they settle on and adhere to. The study found that the leaves from trees along heavily traveled bus routes were up to 10 times more magnetic than leaves from little traveled roads. The pollution can be detected easily and on the cheap with magnets, according to the study’s authors. Even “a strong magnet wouldn’t [attract] the leaf, but it definitely gives you a detectable signal” [National Geographic News], says researcher Bernie Housen.

The authors admit that finding more pollution along bus routes isn’t exactly shocking, but their efforts may help local communities pinpoint and clean up places that have an abundance of air pollution, especially at places where people spend time outdoors, like on bike trails and walking paths. The research team says that using magnets would be an advance in pollution detection because conventional tests for measuring the amounts of these tiny particles are often expensive and time-consuming [National Geographic News]. The study was presented at the Geological Society of America conference in Portland, Oregon.

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Image: flickr / d_vdm

A team of researchers recently discovered that Tamiflu, the leading flu-fighting drug,  is accumulating in rivers downstream from sewage-treatment plants in Kyoto. How is this possible? Tamiflu’s active ingredient, oseltamivir phosphate, is excreted in the urine of people taking the medication. Concerns are now building that birds, which are natural influenza carriers, are being exposed to waterborne residues of Tamiflu’s active form and might develop and spread drug-resistant strains of seasonal and avian flu [Science News]. The resistant virus strains would be of the conventional seasonal or avian flu variety, not the H1N1 swine flu strain that is currently pandemic in humans. Seasonal flu, however, kills thousands of people each year.

Study coauthor Gopal Ghosh explains that the team took measurements during normal flu season, and found concentrations that seem “high enough to lead to antiviral resistance in waterfowl” [Science News]. Computer models show that oseltamivir phosphate will survive sewage treatment, but it should break down when exposed to sunlight and its concentrations should decrease by half every three weeks. The high concentrations were found during a period where 1,738 flu cases were reported in Kyoto, according to the study, published in the journal Environmental Health Perspectives. In the United States, Tamiflu is only recommended for the very sick or those with compromised immune system, while Japan has a more liberal policy.

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Image: flickr / law_keven

Just a few days ago, we wrote that laughing gas, or nitrous oxide, has become today’s biggest threat to the ozone layer. So what’s the greatest source of nitrous oxide? Manure, according to new research published in Nature Geoscience.

Nitrous oxide, which also contributes to global warming, is produced naturally and through human activities like agriculture. Fertilizer is a recognized source of the gas, but until now, manure had been largely overlooked. Says researcher Eric Davidson: “[Fertilisers] are extremely important, but that’s only part of the story.” … He says nitrous oxide levels started increasing in the late 19th century “long before we started using nitrogen fertilisers in the 1960’s” [ABC Science]. And as a growing number of people around the globe consume meat, the manure that is an inevitable byproduct of meat production could pump an increasing amount of nitrous oxide into the atmosphere–or we could harness the power-producing potential of the waste.

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Image: flickr / Rennett Stowe

Here’s the good news: Plastic may break down in the ocean in as little as a year, not 500 to 1,000 years as scientists previously thought. Now, the bad news: This degradation could be releasing harmful compounds such as bisphenol A (BPA) into the ocean, according to research presented at the American Chemical Society meeting on Wednesday.

Ocean-borne plastic, such as that in the vast Great Pacific Garbage Patch, has traditionally been viewed as an environmental hazard due to the danger it can pose to sea life and birds. But to find out more about how plastic behaves when in the ocean, researchers acquired water samples from Japan, India, Europe, the United States, and other locations. The results? All the water samples were found to contain derivatives of polystyrene, a common plastic used in disposable cutlery, Styrofoam, and DVD cases, among other things [National Geographic News].

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A study that set out to determine the how many of the fish in our nation’s streams are contaminated with mercury came back with an ominous answer: quite possibly, all of them. Researchers from the U.S. Geological Survey sampled 34 species of fish at 291 stream sites across the country, and found mercury in every single fish they tested. “This study shows just how widespread mercury pollution has become in our air, watersheds, and many of our fish in freshwater streams,” U.S. Interior Secretary Ken Salazar said [Los Angeles Times].

A quarter of the fish had mercury levels that are considered unsafe for people who eat fish regularly, according to the Interior Department. The main source of mercury to most of the streams tested, according to the researchers, is emissions from coal-fired power plants. The mercury released from smokestacks rains down into waterways, where natural processes convert it into methylmercury — a form that allows the toxin to wind its way up the food chain into fish [AP]. But fish with high mercury levels were also found in Western areas that have been mined for gold or mercury.

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Image: flickr / kasperbs

Scientists will venture this summer to the Eastern Pacific Garbage Patch–a blob of discarded plastic twice the size of Texas that’s floating in the Pacific Ocean–in an extensive effort to assess just how detrimental the patch is to the marine ecosystem.

Two boats push off this month to examine and analyze the patch of plastic; one left from San Diego yesterday, the other is set to leave from San Francisco tomorrow. The expeditions will last four weeks and will cost $1.1 million. Researchers from the Scripps Institution of Oceanography in San Diego will conduct a wide range of experiments on the debris’ impact on phytoplankton, zooplankton, fish, whales, birds, salts and fouling communities – groups of organisms that live on the debris. They will spend 10 days traveling to and from the remote region [San Diego Union-Tribune]. Once the researchers are back on dry land, it will take months to fully analyze the samples collected during the voyage.

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The Chesapeake Bay was once carpeted with oysters, but that was before centuries of overfishing, pollution, and disease took their toll: Today the oyster population has been reduced to less than 1 percent of its historical population. But a new restoration effort has shown unprecedented progress in bringing the bivalves back. In the Great Wicomico River, a tributary of the Bay, researchers have created a 87-acre oyster colony that contains about 185 million oysters.

The Chesapeake’s oyster reefs were destroyed by centuries of watermen towing rakelike metal “dredges” and silted over by dirt flowing from the mid-Atlantic’s farms and growing cities. The final blow came in the mid-20th century: A pair of new diseases killed oysters by the millions. Now, in many places, the bay bottom is a flat expanse of green mud. “Just picture, you know, a clear-cut forest,” said Kennedy Paynter, a biology professor [Washington Post].

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A new political fight is brewing over where to locate a mercury storage facility, as state officials and residents around the seven sites in consideration have grown alarmed at the prospect of the federal government forcing thousands of casks of the toxic metal on them. Ironically, the conflict began when the federal government passed a law to forbid sending the dangerous metal abroad, but nobody seems eager to keep it at home.

Last year, then-Senator Barack Obama sponsored a bill to bar mercury exports beginning in 2013, and President Bush signed it. The bill also requires the Department of Energy to identify a safe, long-term storage site for up to 17,000 tons of mercury, which is so dense that it would fill less than half of an Olympic-size swimming pool. That includes stockpiles held by the federal government, as well as commercial supplies [AP]. The seven sites in consideration for the storage facility are scattered across the country, in South Carolina, Missouri, Colorado, Nevada, Idaho, Texas, and Washington.

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Human beings are increasingly making their homes on the coasts of continents, but this demographic shift is taking a toll on a sensitive coastal ecosystem that is often overlooked: seagrass meadows. A new analysis of seagrass abundance around the world found that 27 percent of these meadows have disappeared since 1879, and the rate of loss is accelerating. The study’s authors write: “Seagrass loss rates are comparable to those reported for mangroves, coral reefs and tropical rainforests, and place seagrass meadows among the most threatened ecosystems on earth….. Our report of mounting seagrass losses reveals a major global environmental crisis in coastal ecosystems, for which seagrasses are sentinels of change” [Nature News].

Endangered species expert Susanne Livingstone notes that despite these losses seagrass rarely makes it into the public consciousness. “It’s probably because they’re not as sexy [as corals], they’re not as attractive,” she says. “They’re just as ecologically important if not more so” [Nature News]. Seagrass meadows provide grazing for a variety of marine animals, including the green turtle and the manatee-like dugong. The coastal areas also serve as nurseries for fish; both coral reefs and commercial fisheries would feel the impact if seagrass meadows vanish.

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Global warming is expected to cause such alarming climate disruptions that talk of hurricanes and heat waves can overshadow another drastic process at work: Burning fossil fuels and otherwise producing excess carbon dioxide makes oceans and other bodies of water more acidic, as the water absorbs the gas. This acidification can change a fish’s physiology in ways that were previously unpredicted and could affect the fish’s survival, according to a study in Science.

Scientists raised groups of white sea bass in water of varying concentrations of carbon dioxide. They found that the fish in the most highly acidified water had the largest rock-shaped ear bones, known in biology parlance at otoliths. That contradicts what the researchers had hypothesized: The ear structure in fish, known as an otolith, is made up of minerals. Scientists knew that increasing carbon dioxide in the oceans — absorbed from the atmosphere — is making the sea more acidic, which can dissolve and weaken shells. They wondered if it also would reduce the size of the otoliths [Los Angeles Times]. Instead, the ear bones of fish growing in the tank with six times as much carbon dioxide than normal were 15 to 17 percent larger than normal. An water with a CO2 concentration about 3.5 times higher than current levels yielded fish with otoliths that were 7 to 9 percent larger than those raised in water with today’s carbon dioxide levels. That’s the CO2 level predicted by the year 2100.

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Cleveland’s Cuyahoga River caught on fire 40 years ago June 22 when oily garbage floating in it was ignited, probably by sparks from a passing train. In turn, the fire sparked the creation of environmental agencies such as the Environmental Protection Agency, along with passage of 1972’s Clean Water Act. And the river, once a dumping ground for industrial waste and an icon for environmental disrepair, today supports more than 60 species of fish along with beavers and various bird species, and serves as an example of environmental restoration.

The river’s recovery is an inspirational account of how even the most putrid bodies of water could be cleaned up. Indeed, the first time [Cleveland resident] Gene Roberts fell into the Cuyahoga River, he worried he might die. The year was 1963, and the river was still an open sewer for industrial waste. Walking home, Mr. Roberts smelled so bad that his friends ran to stay upwind of him. Recently, Mr. Roberts returned to the river carrying his fly-fishing rod. In 20 minutes, he caught six smallmouth bass. “It’s a miracle,” said Mr. Roberts, 58. “The river has come back to life” [The New York Times].

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