News Bytes of the Week--Cell phones: The new cigarettes?

Peppers fingered as salmonella culprits; Does soy lower sperm count?; Robot surveillance dragonfly takes flight; and more …
little boy on cell phone brain


Cell phones—The new cigarettes?
There has been a raging debate over whether cell phones—or more specifically electromagnetic radiation that they emit—up a person's cancer risk. The latest chapter: Ronald Herberman, director of the University of Pittsburgh Cancer Institute, this week warned consumers to limit exposure to cell phone radiation—and alerted parents to beware of possible effects on their kids' developing brains. Although the evidence remains controversial, he is convinced that the radiation poses a risk to human health. As he pointed out, a number of countries, including France, Germany and India, have already issued such warnings to their citizens. Herberman outlined 10 ways to reduce exposure. Among them: reduce cell phone use, use a hands-free earpiece, switch ears while chatting to limit radiation concentration in one spot, and avoid using mobile phones in public places to limit second-hand radiation. In particular, he cautions parents about the possible effects of cell phone radiation on children. He indicates that kids should only be allowed to use these devices in cases of emergency, as their developing brains are more likely to be susceptible to possible side effects. He said recent studies indicate that "living tissue is vulnerable to electromagnetic fields within the frequency bands used by cell phones." Worried? Perhaps you should be. But that doesn't mean you should hang up altogether, Herberman says. As he noted in his memo: "Our society will no longer do without cell phones." But he says there's enough biological data to indicate that consumers should take precautions. Herberman also called on the cell phone industry to improve current technologies to limit radiation risks. The U.S. Food and Drug Administration did not respond to requests for comment, but the agency says on its Web site that no clear link exists between cell phone usage and cancer.

Soy vey! Does eating tofu lower sperm count?
Do real men eat soy? Perhaps. But if they want to become fathers, they may want to limit their tofu intake. A new study shows that downing soy products may lower sperm count. The reason, according to the research published in the journal Human Reproduction (pdf): soy beans contain high amounts of phytoestrogens, organic compounds that mimic the female hormone estrogen in the human body and, in animal studies, have been shown to reduce testosterone levels. Lead study author Jorge Chavarro, a research fellow in the Department of Nutrition at the Harvard School of Public Health, and his colleagues found that men who ate at least half a serving a day of soy had, on average, 34 million fewer sperm per milliliter than those who skipped it. But Chavarro doesn't recommend you give up the soy burgers—at least not yet. He notes that the study was limited (99 men) and that more research is needed to prove that tofu actually reduces male fertility.

Found: FDA officials link salmonella outbreak to Mexican-grown jalapeño
Forget tomatoes. At least for now. The U.S. Food and Drug Administration (FDA) has a direct link to hot peppers as a culprit in the salmonella poisoning that has sickened 1,250 people in the U.S. and Canada since April. FDA investigators announced Monday that they found a strain of salmonella that matched the one in victims in a single jalapeño pepper grown in Mexico. The contaminated pepper was uncovered at the Argricola Zaragoza, Inc., packaging facility in McAllen, Tex., a town near the border. The firm has recalled all jalapeños distributed since June 30. The product is known to have shipped to customers in Georgia and Texas. Still unknown: whether the pepper was contaminated on the farm where it was grown, in the packaging facility or while it was being transported from one to the other. FDA officials say that tomatoes were not necessarily blameless in the salmonella outbreak, which landed some 200 people in the hospital. But they insist they are okay to eat now. Jalapeños, however, are still a no-no. The FDA yesterday warned people to steer clear of raw jalapeños. (It says that the elderly, infants and people with compromised immune systems should also avoid closely related serrano peppers.) FDA investigators plan to retrace the route of the tainted jalapeños from the packing plant back to the farm in Mexico where they were grown, to determine the contamination point. They also plan to check out distributors of peppers packaged at the Texas plant to determine if they played a role in the salmonella outbreak.

Climatic Conundrum: Could wildfires chill the warming Arctic?
Alaskan residents who watched as wildfires claimed a record 10,000 square miles (25,900 square kilometers) of land in 2004 may take cold comfort in the fact that the choking smoke endured during wildfire season could blunt some of the effects of global warming. Researchers from the National Oceanic & Atmospheric Administration (NOAA) analyzed the short-term climatic impact of smoke from wildfires that swept Alaska and western Canada in 2004, burning 22,000 square miles (57,000 square kilometers) in total. They report in the Journal of Geophysical Research that the billowing clouds may have a cooling effect on the Arctic, where dwindling ice sheets have researchers worried about the potential for sudden climate changes to come. They say that smoke carried north on the wind absorbs some of the sun's rays and perhaps lessens the impact of global warming for weeks or months at a time, to a degree that depends on the soot's thickness, the sun's elevation and the brightness of the ice or water surface. They note signs that the 2004 wildfires had atmospheric effects as far north as Greenland and the islands above Norway and down south to the Gulf of Mexico. The only hitch: Particles that land on snow or ice might actually cause it to melt faster. Still, , NOAA says, it is possiblethe Arctic might benefit if wildfires intensified—a distinct possibility as global warming leads to drier summers up north.

Meet Makemake, the fourth dwarf planet
Astronomers have upgraded a distant body discovered in 2005 to the category of dwarf planet, the controversial designation created two years ago by the Paris-based International Astronomical Union (IAU) to deal with planetlike bodies far out in the solar system. The IAU decided at a meeting last week that the object formerly known as 2005 FY9 (or unofficially, "easterbunny") will henceforth be known as Makemake (pronounced MAH-kee MAH-kee) for the Easter Island Polynesian god of fertility and creator of humanity. That makes it the fourth dwarf planet, joining Ceres, Eris and Pluto, and the third "plutoid," or dwarf planet beyond Neptune. (Ceres resides in the asteroid belt between Mars and Jupiter.) Slightly smaller than Pluto and nearly as bright, reddish Makemake is one of the largest transneptunian objects in the solar system. Its discovery, along with that of Eris and similar specimens, precipitated the IAU's decision to create a separate category for round objects in the solar system that have not swept clear their regions of competing debris. This new criterion robbed Pluto of its prior status as a planet.

Not lost in space: NASA plans GPS-like system for return to the moon
NASA has coughed up $1.2 million for a navigation system that will help astronauts find their way around the lunar surface when they return in 2020. The Lunar Astronaut Spatial Orientation and Information System (LASOIS) is designed to function much the same way as a global positioning system (GPS). The major difference: the moon version will rely on signals from lunar beacons, stereo cameras and orbital imaging sensors instead of from GPS satellites to map coordinates. A group of The Ohio State University (O.S.U.) researchers are working with NASA Glenn Research Center, the Massachusetts Institute of Technology and the University of California, Berkeley, to develop the LASOIS. This is old hat for Ron Li, an O.S.U. professor of civil and environmental engineering and geodetic science heading up the project, who was part of a team that developed software that helps NASA scientists guide the Spirit and Opportunity rovers as they roam the Martian landscape. NASA mapped portions of Mars by comparing images taken by a high-resolution imaging science experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter with those snapped by Spirit and Opportunity on the Red Planet's surface. Li explained how the system works this week during a conference held at NASA Ames Research Center at Moffett Field, Calif.: Images taken from space will be combined with surface shots to create maps of lunar terrain; motion sensors on lunar vehicles and clipped onto the astronauts' spacesuits will help computers pinpoint their locations; signals from lunar beacons, the lunar lander and base stations will give astronauts a picture of their surroundings similar to what drivers see when using a GPS device on Earth.

Robot surveillance dragonfly takes flight
Researchers at the Delft University of Technology in the Netherlands earlier this week unveiled a small, remote-controlled aircraft weighing just 0.11 ounce (3.1 grams) and with a four-inch (10-centimeter) wingspan—just large enough to accommodate an onboard camera. The DelFly "micro air vehicle," which flaps its wings and looks like a dragonfly, can fly for about three minutes at a speed of 16.4 feet (five meters) per second. The team hopes the DelFly Micro—Delft's third-generation robot flyer (after the 0.81-ounce, or 23-gram, DelFly I in 2005 and the 0.56-ounce, or 16-gram, DelFly II a year later) will capture images from nooks and crannies that bigger cameras cannot reach. The DelFly II's camera transmits TV-quality images, allowing it to be operated from a computer using a joystick and giving the person controlling the mechanical insect the feeling of being inside the cockpit of a miniature aircraft. The researchers are hoping to further develop the DelFly Micro's camera so that it can be used the same way. They are also working to give it DelFly II's ability to hover (like a hummingbird) and fly backward. Next on the agenda: the DelFly NaNo, projected to weigh a single gram and have a two-inch (five-centimeter) wingspan. In addition to making ever-smaller robots, the researchers want to add image-recognition software that will let the DelFlys zoom on their own without getting tangled in a tree or crashing into a wall.

Lime-aid: Acid oceans, warming globe? Just add lime
By adding lime to seawater, scientists hope to slow or even reverse some of the worst effects of climate change by cutting the acid in oceans caused by the excess carbon dioxide released by an industrialized world. When the world's seas—which absorb the greenhouse gas—become acidic, coral and other shelled sea life suffers. But by adding lime (derived from the stone formed from billions of dead coral), the acid is neutralized and even more CO2 can be absorbed without upsetting marine denizens—or so goes the theory. First proposed in the 1990s by ExxonMobil, the plan was dismissed because of the hundreds of millions of dollars in energy costs, along with the CO2 that would have been emitted in the process of making and transporting the lime. But researchers backed by another oil giant—Shell—now believe they can get over those hurdles by producing the lime in areas that are rich in limestone and have readily available cheap electricity, such as solar. "There are many such places," says management consultant Tim Kruger, the brains behind this renewed idea. "For example, Australia's Nullarbor Plain would be a prime location for this process, as it has [2,400 cubic miles] 10,000 cubic kilometers of limestone and soaks up roughly 20 megajoules per meter squared of solar irradiation every day." Of course, that wouldn't even put a dent in the 7.7 billion tons (7 billion metric tons) of greenhouse gases that the U.S. alone emits. And no one knows what the other consequences of adding that much lime to the ocean might be.

Back to the Future?: 14-million-year-old fossil reveals a warmer Antarctic
Was the Antarctic once a balmy place? Researchers report in the British journal Proceedings of the Royal Society B that a fossil of a tiny crustacean offers proof that it had a relatively toasty clime as recently as 14 million years ago. The rocks in eastern Antarctica's McMurdo Dry Valleys region yielded the fossil of an ostracod—a shrimplike crustacean that lived in an ancient lake. The tiny crustaceans need liquid water to survive—unavailable in today's Antarctic where temperatures average –13 degrees Fahrenheit (–25 degrees Celsius), but possible eons ago when the climate there was more like Alaska's. The living progeny of the ancient critter don't get any closer to Antarctica than the surrounding seas, but the fossil indicates that the bone-dry landscape, often compared to that of Mars, once was warm enough to have liquid water. What it doesn't reveal is what caused the shift to a colder climate, a process that may be reversing itself at present.

E-squire? Men's mag cover to feature electronic ink news ticker
Esquire magazine plans to give its readers both the written—and digital—word in its October issue, which will feature so-called electronic ink. E Ink, the company that supplies the technology for Amazon's popular Kindle and the Sony Reader e-books, is behind the devices—paperlike display cells that will allow black-and-white words and images to crawl news ticker–style across the cover. A tiny battery will power the display for about 90 days before it runs out of juice. (The issue will also include a foldout ad on the back cover that will also use electronic ink.) Only 100,000 issues of the mag (circulation: 720,000) will feature the snazzy technology; these coveted few will be delivered via refrigerated vehicles designed to preserve the batteries. Esquire editor David Granger told The New York Times that he wants to shake up the world of magazines, which have looked basically the same for the past 150 years. He hopes that in several years the budding technology will have advanced enough that this first attempt will look like "cell phones did in 1982."

Rights & Permissions
Share this Article:


You must sign in or register as a member to submit a comment.
Scientific American MIND iPad

Give a Gift & Get a Gift - Free!

Give a 1 year subscription as low as $14.99

Subscribe Now >>


Email this Article