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The article reports that in November 1846, the Donner party--a wagon train of 81 settlers headed west across the Sierra Nevada, California--became hopelessly snowbound. Recently, archaeologists have discovered the exact location, near Alder Creek 11 kilometers away from a lake, where 22 settlers hunkered down. The team, which described its findings at a symposium held by the Society for Historical Archaeology in Sacramento, California, found no human burials or signs of cannibalism such as cooked human bones.

The article reports that an Indian advocacy group plans to release a massive report on biodiversity that the Indian government commissioned but decided to shelve. The 1300-page report, entitled "Securing India's Future: Final Technical Report of the National Biodiversity Strategy and Action Plan," was commissioned in 2000 by the Ministry of Environment and Forests to look at how the country should manage its rich biodiversity. The report is part of India's obligatory response as a signer of the Convention on Biodiversity.

Scientists have for the first time genetically modified plants to contain a particularly healthy kind of fatty acid in their seeds. The most beneficial of so-called omega-3 fatty acids are found only in fish, so growing omega-3-rich transgenic plants instead could increase public consumption while relieving pressure on fisheries, researchers say. The oil and fat in food consist of fatty acids, which are chains of carbon and hydrogen atoms. Because most people don't eat enough fish to get the recommended amount of eicosapentaenoic acid (EPA), and because fisheries are already in decline, researchers have been trying to engineer plants with enzymes to make EPA.

This article reports that hummingbirds originated from Europe. A few fossils of what appeared to be primitive hummingbirds have turned up in the primitive times, but as far as anyone knew, their modern descendents never set wing in Eurasia. Gerald Mayr, a scholar, describes the discovery in the May 7 issue of the journal "Science." The new fossil called Eurotrochilus demonstrates that in the primitive times, hummingbird ancestors had evolved the main features of living hummingbirds, such as a long, slender beak adapted for feeding on nectar, by 30 million years ago.

Plant pathologists across the U.S. are scrambling to halt the potential spread of a fungus-like pathogen that kills oaks. In a nightmare come true, the pathogen, Phytophthora ramorum, was found in March 2004, in a nursery that has shipped potentially infected plants to more than 600 nurseries in 39 states. The pathogen causes lethal trunk infections in several kinds of oaks, and it has killed tens of thousands in California. Scientists are also tweaking their plans for a survey of southeastern states, many of which have broad stands of susceptible oaks.

Cites a study conducted by ecosystem scientist Bruce Peterson and colleagues in Woods Hole, Massacusetts-based Marine Biological Laboratory with hydrologists from the U.S. and Russia to track the water flow of the Arctic Ocean and analyze discharge records for six major Eurasian rivers, published in the December 13, 2002 issue of the journal 'Science.' impact of global warming on increase in the flow.

Reports on the fellowships announced by the Howard Hughes Medical Institute (HHMI) in Chevy Chase, Maryland, that will give each of 20 top biologists $1 million over four years to enhance undergraduate education. Comments of Peter Bruns, vice president of HHMI for grants and research, on undergraduate science curricula; Utility of the money to the grant recipients; List of the 20 HHMI grant recipients.

The article offers information on the live online chat about genetically modified foods on November 15, 2012, sponsored by "Science" journal.

This article reports that the U.S. Environmental Protection Agency proposed new rules that would cut almost in half the maximum amount of fine particulates that people should breathe over 24 hours. However, the agency did not reduce the average annual amount allowed, rejecting the advice of its own scientists and its scientific advisory panel. Many studies have shown that the inhalation of small particles can harm health and even lead to the premature death of people suffering from lung and heart disease. The agency proposes lowering the standard for 24-hour exposure for PM 2.5 from 65 micrograms per cubic meter. Lung Chi Chen of the New York University School of Medicine in New York City and his colleagues exposed heart disease-prone mice to polluted air.

The article reports on the discovery of a dinosaur fossil. There's no shortage of anatomical evidence that birds evolved from dinosaurs. But paleontologists have still had to contend with a slightly embarrassing gap in the fossil record. The oldest known bird fossil, Archaeopteryx, is much older than fossils of its closest dinosaurian relatives. Archaeopteryx is known from several 150-million-year old specimens found in Upper Jurassic limestone in Germany. One of those older dinosaur relatives, a contemporary of Archaeopteryx, was described at the annual meeting of the Society of Vertebrate Paleontology. Collected in 2000 from Upper Jurassic rock layers in eastern Wyoming, the fossil's bones were so delicate that William Wahl, of the Wyoming Dinosaur Center in Thermopolis, needed several years to prepare them.

This article reports that the U.S. House of Representatives yesterday passed legislation that would alter the Endangered Species Act (ESA). The bill, introduced by a longtime opponent, was pushed through at a whirlwind pace, and critics say it will weaken protections of species. Representative Richard Pombo has made reform of the act a priority since coming to the Congress in 1993. He and other critics say that it has caused economic harm to landowners while not adequately helping endangered species recover. Becoming chair of the House Resources Committee in 2003 gave him the clout he needed. The bill contains several major changes in the 32-year-old ESA. It would eliminate so-called critical habitat provisions, land or water that the Fish and Wildlife Service designates as necessary for a species to recover.

The article reports on Representative Richard Pombo's plan to substantially loosen existing restrictions on the U.S. landowners and businesses as against the restrictions imposed by the Endangered Species Act (ESA). Environmentalists say this measure would cripple protections for imperiled species. Pombo also wants to compensate landowners for the fair market value of any development or other activity that would impact endangered species that the government has rejected. The bill related to this doesn't estimate the annual cost of such payments involved. In a major change, the bill would repeal a section of the ESA that instructs the Fish and Wildlife Service and the National Oceanic and Atmospheric Administration to designate so-called critical habitat for species, defined as the habitat necessary to help a species recover.

This article reports that life has become close to untenable for the seals and enormous sturgeon in the Caspian Sea from years of overharvesting and habitat loss, combined with pollution and invasive species. The number of beluga sturgeon, the species most harvested for caviar, has plummeted by more than 90% since 1960. Scientists reported that no wild, reproducing Beluga females have been found this year in Kazakhstan, which means there won't be any eggs from which to raise hatchery fish. Ellen Pikitch, director of the University of Miami's Pew Institute for Ocean Science, said that other sturgeon are following in the footsteps of beluga.

The article presents information about Tyrannosaurus rex (T. rex). For the first time, paleontologists have identified a T. rex as female by discovering a type of bone tissue that appears to be related to egg-laying. In a few cases, paleontologists have discovered eggs inside a skeleton allowing them to know for sure they found a female. To compare the Tyrannosaurus fossil with living birds that were at least somewhat comparable in size to the dinosaur, the team cut up the legs of a pregnant ostrich and an emu that had died before laying all its eggs.

This article reports that the National Oceanic and Atmospheric Administration's (NOAA's) National Marine Fisheries Service announced that it is considering listing staghorn and elkhorn corals as threatened. A listing could have broad implications for the management of activities that affect corals from fishing to farming. Around the world, nutrient-rich runoff from agricultural lands, sediment, and warmer waters have stressed the symbiotic zooxanthellae that live within coral. In March 2004, a San Francisco-based advocacy group called the Center for Biological Diversity petitioned NOAA to list three kinds of coral found in U.S. waters as threatened or endangered.

The article reports that human cases of West Nile virus have likely resulted from mosquito species that were not thought to play an important role in spreading the disease, according to a new model of disease transmission in the northeastern U.S. West Nile virus spreads to humans when a mosquito bites an infected bird and then bites a person. In the Northeast, where the disease first appeared in the U.S. in 1999, several species of mosquitoes are involved. Scientists thought that Culex pipiens and Culex restuans bit only birds and that other mosquitoes, such as the common Aedes vexans, were responsible for transmitting the virus from birds to people.

The article informs that archaeologists have fiercely debated whether the first civilization in Mesoamerica emerged from the singular influence of one culture or from the exchange of many. When societies were first forming in Mesoamerica, between 3150 and 2800 years ago, a site now called San Lorenzo was the Manhattan of its day. Some archaeologists have argued that the Gulf Coast Olmec were the" mother culture" of Mesoamerica. A team led by Jeffrey Blomster of George Washington University in Washington, D.C., decided to test this idea by chemically analyzing the pottery. Chemical analysis confirmed that each region produced ceramics locally, but six regions also imported ceramics from the San Lorenzo area.

The article reports a study which suggests that quality control of dietary supplements is a major stumbling block for any study of the widely used compounds. According to a panel of the National Academies of Sciences Institute of Medicine, it reviewed other aspects of complementary and alternative medicine as well. The panel wants to strengthen existing laws and also give manufacturers an incentive to study the efficacy of their products. The report was commissioned in 2002, principally by the National Center for Complementary and Alternative Medicine, to study the growing popularity of alternative medicine and associated scientific and policy issues.

The article presents information on the presence of the chemical perchlorate in the drinking water. The U.S. Environmental Protection Agency (EPA)--has huge implications for the potential scale of cleaning up groundwater, which is contaminated with the chemical perchlorate in many parts of the country. The potential danger of perchlorate is that it can prevent the thyroid from making hormones, leading to hypothyroidism. Adults can store a supply of thyroid hormones, which are important for brain development, but children need iodine every day to make them. In 2002, the EPA released a draft risk assessment that proposed that the safe oral intake of perchlorate was 0.00003 milligrams per kilogram of body weight.

The article reports a preliminary study of temples on Maui, described in the January 7, 2005 issue of the journal Science, which suggests evidence related to religious states that emphasized divine kingship and emerged on several Hawaiian islands. This may have happened within a single generation just as the stories suggest. Archaeologist Patrick Kirch of the University of California, Berkeley, and geochronologist Warren Sharp of the Berkeley Geochronology Center performed another kind of radiometric dating, measuring the ratio of uranium-238 to thorium-230. By dating the coral, which stopped absorbing uranium from seawater once it was cut from a reefó they discovered that eight temples on southeast Maui were all built between 1580 and 1640 C.E.

The article reports a study in which exquisite microfossils were brought to light by dissolving 850 million-year-old rocks. The research could represent the most ancient fungi ever discovered. The discoverer also argues that more enigmatic fossils, dating to around 1400 million years ago, are the same fungi, but other experts would like more evidence for that claim. The new examples were found by paleontologist Nicholas Butterfield at the University of Cambridge, United Kingdom. The key feature, as Butterfield describes in the February 2005 issue of Paleobiology, is that these filaments joined to form networks of loops.

The article discusses the effect of pesticides on wildlife. The chemicals that make up these pesticides are chiral. Although the mirror-image versions, or enantiomers, of a molecule have the same chemical properties, they can interact with enzymes in different ways. Researchers showed that enantiomers could vary in their toxicity, although most of this work was done in banned chemicals. The researchers also found that the enantiomers of two organophosphates differ in how they linger in sediment.

The article focuses on three high school students who landed a $100,000 scholarship each by winning top honors at the annual Siemens Westinghouse science competition held in Washington D.C. Taking first place in the individual category was Aaron Goldin, a senior at San Dieguito High School Academy, in Encinitas, California. Goldin invented a device that uses a gyroscope to generate electricity from ocean waves. Starting out as a volunteer in a lab at Scripps Institution of Oceanography in La Jolla, he became involved in a project to design a wave-powered research vehicle. Yueqi Guo and Xianlin Li, both seniors at the North Carolina School of Science and Mathematics in Durham, won the team category for their work on a gene that might be helpful in diagnosing breast cancer.

The article informs that a new study raises concerns about very low levels of exposure of Benzene. Workers in Chinese shoe factories who inhaled less than 1 part per million (ppm) of benzene, an exposure considered safe under U.S. occupational guidelines, had fewer white blood cells than did unexposed workers. To determine whether blood cells are affected at even smaller exposures, an international group of researchers compared 250 workers exposed to benzene-laden glues in two shoe factories in China to 140 unexposed workers who sew clothes in other Chinese factories. As expected, workers exposed to benzene at levels of 1 ppm and higher had fewer white blood cells, such as granulocytes and B cells, than did unexposed workers. These workers had on average 15% to 18% fewer granulocytes and B cells than unexposed workers, raising concerns about effects on bone marrow.

The article reports a study showing that immune cells are more active in autistic brains, causing increased inflammation, and remain that way for much of life. Although the cells involved are normally important for proper brain development and function, it's not clear whether this inflammation is a cause, or a result, of autism. A team led by neurologists Carlos Pardo and Diana Vargas, at Johns Hopkins School of Medicine and colleagues has now looked at tissue from the brains of 11 people with autism, aged 5 to 44 years, and seven brain autopsy samples from nonautistic people.

The article focuses on a study on health risks to children from indoor pesticides launched by the U.S. Environmental Protection Agency (EPA) which has plans to give it another round of external review. The study, called the Children's Health Environmental Exposure Risk Study (CHEERS), has come under fire for alleged ethical shortcomings, and for being partly funded with industry grants. Working with research contractors, scientists plan to study 60 children under the age of 3 years. The Environmental Working Group objected to the fact that the $7 million study was being funded with a $2 million grant from the American Chemistry Council, an industry group which represents pesticide manufacturers.

The article focuses on a study in which archaeologists have discovered a rare trove of finely painted and beautifully sculpted drinking vessels on the shores of Lake Titacaca, Bolivia. The 1000-year-old jugs, 20 of which are unbroken, are shaped like human heads, offering a glimpse of the people of one of the most important pre-Colombian cultures in the south central Andes, the Tiwanaku. The vessels were found by Risto Kesseli and Antti Korpisaari of the University of Helsinki, working with Bolivian colleagues, in August 2004 while excavating on an island called Pariti, a particularly sacred site for the Tiwanaku.

The article focuses on the research undertaken to trace out the possible reasons for the extinction of California condor, Teratornis, western black vulture and other herbivores during the Pleistocene period. The late Pleistocene was a difficult for large animals in North America as the climate was changing, and human hunters had marched into the continent. Although the ultimate cause of the extinction of the mammoths and other large herbivores is still debated, it's clear that their demise had drastic effects that cascaded through food webs

The article focuses on harmful effect of artificial fragrances and other non-toxic chemicals in detergents on mussels and other aquatic wildlife. These synthetic musks interfere with the transport proteins that pump many kinds of toxins out of cells, which could allow them to build up to dangerous levels. The transport proteins remain impaired for up to 2 days after exposure to the musks. Lab experiments have shown that environmental pollutants, such as polyaromatic hydrocarbons, can have the same effect on transporters in sea urchins, fish, mussels, and other aquatic organisms, ultimately leading to toxicity.

The article reports that like reclusive celebrities, tyrannosaurs have risen to evolutionary stardom while keeping their origins shrouded in mystery. The fossils, so well preserved that one even shows a"protofeather" fuzz covering the body, show that tyrannosaurs began evolving the deadly design of their heads before their bodies morphed into powerhouses. The new specimens come from western Liaoning Province in China and were studied by Xing Xu and colleagues from the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, along with Mark Norell of the American Museum of Natural History in New York City.

The article talks about marine reptiles. Sneaking up on an unwary fish in dim waters, the 4-meter-long reptile is poised to strike. Its long neck, pulled back in a sideways "S," suddenly straightens, whipping the head forward. Sucking in liters upon liters of water, the animal grasps the fish with its fangs. This previously unknown style of predation, in which the expansion of a neck creates suction, has now come to light thanks to a new skeleton of the long-extinct reptile, Dinocephalosaurus orientalis. Scientists of University of Chicago and Institute of Vertebrate Paleontology and Paleoanthropology in Beijing describe the fossil in the September 24, 2004 issue of Science.

This article cites a study, conducted by archaeologist Barry Rolett and geographer Jared Diamond, which focuses on Polynesians' environmental impact, with a focus on the Marquesas, French Polynesia. When Polynesians spread across the Pacific, some flourished in what became island paradises. Others deforested the islands they colonized and, as on Easter Island, sank into warfare and cannibalism. After crunching the numbers, the two discovered what mattered most: Warmer, wetter islands were more likely to have resisted deforestation, as were big islands, islands whose high, rugged terrain made it hard to grow crops, and those dusted regularly with soil-enriching volcanic ash.

This article presents information about a group of fossils shows that an adult dinosaur died together with 34 hatchlings. The new specimen contains the partial skeleton of an adult Psittacosaurus, a herbivorous dinosaur with a parrotlike beak. Researcher Varricchio, Jinyuan Liu of the Dalian Natural History Museum in China, and their colleagues are more interested in what the fossils say about the Psittacosaurus's life. Paleontologists have found powerful evidence before that dinosaurs protected their nests.

The article cites that new fossils have given paleontologists a view of an ancient arms race between predator and prey. By counting the chewed-off arms on fossil crinoids, researchers have shown that these filter-feeding cousins of starfish suffered ever fiercer attacks during a period when fish and other major predators were diversifying. Just as swords inspired the invention of chain mail, the history of life hints at many arms races between predators and prey. But with the remnants of the carnage long turned to stone, it can be difficult to prove that the evolution of bigger teeth, for instance, actually did encourage the evolution of defenses such as thicker armor.

When the ancestors of modern whales first dipped into the seas, it was the first step of a radical evolutionary journey: Arms morphed into flippers, and legs eventually vanished. But limbs weren't the only thing that needed to change. New whale fossils are revealing how the animal's ears were transformed in a process of compromise: Early whales had ears adapted for hearing both on land and underwater. Land mammals perceive sound that enters the ear canal and hits the eardrum. The eardrum is connected to three small bones — ossicles called the malleus, incus, and stapes — that amplify and transmit the vibrations of the eardrum to the fluid-filled cochlea, where tiny hairs turn the sloshing into nerve signals.

Erik Stokstad was a creature of superlatives. As big as a bull elephant, T. rex weighed 15 times as much as the largest carnivores living on land today. Now, paleontologists have for the first time charted the colossal growth spurt that carried T. rex beyond its tyrannosaurid relatives. "It would have been the ultimate teenager in terms of food intake," says Thomas Holtz of the University of Maryland, College Park. Growth rates have been studied in only a half-dozen dinosaurs, none of them large carnivores. That's because the annual growth rings in bone used to determine age tend to get resorted in the weight-bearing bones of tyrannosaurids and other big meat-eaters.

With an impressive array of feathers, the 147-million-year-old Archaeopteryx is clearly dressed like a bird. But almost all of its skeleton, from its teeth to its long, bony tail, resembles that of a carnivorous dinosaur. Paleontologist Angela Milner of the Natural History Museum in London, Great Britain, and colleagues inspected the brain of the so-called London specimen of Archaeopteryx, one of seven known fossils of the magpie-sized creature. Although the brain itself isnít preserved, during life the brain pressed against the skull, leaving an impression of its lobes. The new view of the anatomy will help explain the evolutionary transition from dinosaurs to birds and the evolution of flight, says Lawrence Witmer, a paleontologist at Ohio University College of Osteopathic Medicine in Athens.

Government agencies should evaluate the safety of new food crops based on what they contain rather how they were created, according to a report released on July 27, 2004 by the National Academy of Sciences. The panel, chaired by Bettie Sue Masters of the University of Texas Health Science Center in San Antonio, distinguished between crops that are genetically engineered — having a gene deleted or transferred between species — and those that are genetically modified by other methods. Even crops whose genes are modified and shuffled by conventional breeding can turn out to have harmful effects, such as heightened levels of naturally occurring toxic compounds.

In a legal gambit aimed against global warming, the attorneys general of eight states yesterday sued the five largest emitters of carbon dioxide (CO2) in the United States for creating a public nuisance. In 2002, environmental groups sued the Overseas Private Investment Corp. and the Export-Import Bank of the United States for not conducting environmental reviews on financing power plants. And last year, Maine, Massachusetts, and Connecticut sued the Environmental Protection Agency for not regulating CO2 as a pollutant under the Clean Air Act.

Physicists can now detect the spin of a single electron inside a glassy chip of silica. The feat marks a significant step toward seeing individual atoms inside a material— a prerequisite for building a microscope that could map the three-dimensional structure of molecules— and may prove critical for so-called spintronic devices, including some kinds of quantum computers. Researchers can already visualize individual atoms with scanning tunneling and atomic force microscopes, but only on the surface of a sample.

Plant pathologists will be getting their first look at the complete genome of two species of Phytophthora, a fungus like pathogen that harms a wide array of plants. Sequencers unveiled the genome of Phytophthora ramorum, the cause of sudden oak death, and also of Phytophthora sojae, which rots the roots of soybeans. The nearly $4 million effort, funded by the U.S. Department of Energy, the U.S. Department of Agriculture, and the National Science Foundation, began in 2002. The sequence will help researchers find out much more about how the pathogen and its hosts interact, and that could lead to disease-resistant plants, says Chuanxue Hong, a plant pathologist at Virginia Tech's Agricultural Research and Extension Center in Virginia Beach.

An oval blob less than a fifth of a millimeter long, discovered in ancient Chinese rocks, is the oldest known fossil of an animal with a mirror-image symmetry, a team of paleontologists reports. For decades, paleontologists have been eagerly looking for the roots of the so-called Cambrian Explosion, an apparent eruption of many-celled animals about 540 million years ago in which all the major animal body plans appeared. The authors of the new study said that their find shows that key features of bilaterians are preserved in rocks some 580 million to 600 million years old, and thus that the genetic tool kit used to assemble more sophisticated body plans was present long before the Cambrian Period.

Genetic engineering has had a huge economic success with crops that can withstand herbicides, particularly glyphosate, which is safe, cheap, potent, and environmentally friendly. In the 21 May issue of the journal Science, a team describes a new way of making plants resist glyphosate. If the plants make it to market, they could lower the price of genetically modified crops and stimulate further innovation. The study was conducted by researchers with Verdia Inc. and Maxygen Inc., both in Redwood City, California, and Pioneer Hi-Bred International Inc. in Johnston, Iowa.

Songbirds can migrate for thousands of kilometers at night and in poor weather yet still end up in the right place. Now, in a logistical tour-de-force, three researchers have revealed how the birds get their bearings before takeoff each night: They set their course according to a magnetic compass they calibrate at sunset. By watching which direction the birds try to hop out, researchers try to discern which sense the birds rely on most. The researchers followed the birds as they flew through the night, tracking them with a meter-tall antenna mounted on top of a battered 1982 Oldsmobile. Control birds flew northerly, but those that had been in the altered magnetic field flew westward for the entire night.

The article presents a study by researcher Torben Christensen and colleagues at Lund University in Sweeten, published in February 20, 2004 issue of the journal "Geophysical Research Letters," which reveals that the tundra has become much wetter during the period from 1970 to 2000 and emission of methane appears to have risen by up to 66% during the period. Researchers compared aerial photographs of the Stordalen mire in Abisko region of Northern Sweden taken in 1970 and 2000. Extrapolating from the vegetation patterns of 1970 and 2000, they calculated that the shift in plants has caused a rise in methane production.

There's apparently no holding back the transplanted genes of genetically modified (GM) crops. Infamous for having turned up in taco shells, now transgenes have been found in commercially available seeds of traditionally bred crops. A report released by the Union of Concerned Scientists, an advocacy group based in Washington D.C., finds transgenes in seeds of many kinds of corn, canola, and soybeans in the U.S. DNA from GM crops was pervasive at low levels. One laboratory found engineered DNA in half the corn and soybean varieties and all canola varieties. The other laboratory found transgenes in five out of six varieties for all three crops. The report urges the U.S. Department of Agriculture to determine the extent of contamination with a full-scale testing program, among other recommendations. There's no known health risk from any of the GM crops that are commercially grown.

It may not make great action footage for nature documentaries, but plants are in constant battle with each other and with soil pathogens that threaten to kill or stunt them. Plants that escape their natural soil-borne enemies and strike up alliances with friendly microbes, can become aggressive invaders. The idea was first proposed 2 years ago by John Klironomos of the University of Guelph in Canada based on greenhouse experiments that suggested invasive weeds thrive when they're transplanted into soil lacking the pathogens that plague them in their native environment. New research by Ragan Callaway of the University of Montana, Missoula and colleagues strengthens that conclusion. The group studied spotted knapweed, a European plant that is now a pervasive weed in the western U.S. First, they planted seeds in sterilized and nonsterilized soil from both continents. Plants in pathogen-free soil from North America grew up to 148% more than those in the nonsterilized U.S. soil.

Multiple safeguards are needed to lessen the chance that genetically modified organisms might harm humans or the environment. That's because no single biological barrier to gene flow is likely to be completely effective. Meanwhile, two European countries have taken cautious steps toward allowing more planting of genetically modified crops. Transgenic crops' pollen is hobbled so it doesn't spread herbicide-resistance genes to weeds, for example, and growth-enhanced salmon have been sterilized to prevent them from competing with native species if they escape from their ocean pens.

The largest survey yet of pollutants in salmon, reported in the January 9, 2004 issue of "Science," has found that farmed fish have higher levels of polychlorinated biphenyls (PCBs) and other organochlorine compounds than do wild-caught salmon. The authors argue that consuming more than one serving of farmed salmon per month may hike the risk of cancer. Other experts say the risk is outweighed by the health benefits of eating farmed salmon. Salmon is a good source of protein, vitamin D and heart-friendly fats.

The largest survey yet of pollutants in salmon, reported in the January 9, 2004 issue of the periodical "Science," has found that farmed fish have higher levels of polychlorinated biphenyls (PCBs) and other organochlorine compounds than do wild-caught salmon. Consuming more than one serving of farmed salmon per month may hike the risk of cancer. To find out what else is in farmed salmon, the Pew Charitable Trusts' Environment program funded six scientists to sample about 700 salmon from around the world and analyze them for more than 50 contaminants. The source of the compounds, the researchers found, was the oil and meal fed to the salmon. Premenopausal women avoid farmed salmon, because the compounds build up in body fat and linger there for decades, where they can be passed to a woman's fetus during pregnancy or excreted in breast milk.