Because of two missing amino acids, this tomcod can swim through PCBs—and survive.
PCBs are nasty pollutants—they mess with hormones and have been linked to cancer—but until they were banned in 1977, dumping them in US rivers was a common practice for companies like GE. While plenty of wildlife suffered from ingesting PCBs, some fish in the Hudson and other be-sludged rivers evolved an immunity to the poisons, a intriguing example of quick adaptation that scientists have been watching with interest. A recent Economist article focusing on this research describes the fascinating genetic ju-jitsu that allows fish in the Hudson and in the harbor at New Bedford, MA, to keep themselves alive in PCB-contaminated waters. Read More
What’s the News: Scientists have for the first time directly linked freeway vehicle emissions with brain damage. Scientists used a new technique that involved trapping airborne toxins along Los Angeles’ 110 Freeway, freezing them in water, and exposing lab mice to the toxins. “As a society, we need to figure out ways to minimize the level of the very, very nasty particulates we are dumping into the air we breathe,” University of Southern California gerontology researcher Todd Morgan told the Los Angeles Times. “It’s having terrible consequences.” Read More
The furiously evolving species is the bottom-feeding Atlantic tomcod, which lives in areas of the Hudson that were contaminated by PCBs through much of the 20th century.
PCBs, or polychlorinated biphenyls, were first introduced in 1929 and were used in hundreds of industrial and commercial applications, mostly as electrical insulators. They were banned 50 years later, but they don’t simply degrade. Partly because of PCB contamination, a 200-mile stretch of the Hudson River is the nation’s largest Superfund site. [National Geographic]
Despite swimming in PCB-polluted waters and accumulating the chemicals in their systems, the tomcods are alive and well in the river. In a study in Science this week, Isaac Wirgin and colleagues show that this is because in the span of just a few dozen generations, the fish have evolved a resistance to PCBs.
Villagers living in Ecuador’s remote rainforests won a victory in one of the longest-running, most complex environmental lawsuits ever this week. A judge in Ecuador awarded $8.6 billion—with the possibility of another $10 billion or so on top of that—to plaintiffs suing Chevron for polluting the Amazon region during decades of energy exploration. But in a turn of events befitting the tangled web of international environmental law and fights over who should pay for pollution, there’s no guarantee the plaintiffs will actually see that money.
Judge Nicolas Zambrano awarded the $8.6 billion to pay for cleanup and for health care for Ecuadorians made sick by the pollution, plus 10 percent of that total added on top as reparations to the Amazon Defense Coalition. If Chevron doesn’t publicly apologize within 15 days of the ruling—and it isn’t going to—the ruling tacks on another $8.6 billion in punitive damages.
The pollution case itself is full of weird twists and turns. The first thing to know about this mess is that “Chevron” didn’t pollute the region—at least, not under that name.
Chevron does not, in fact, operate in Ecuador today; the American company acquired the lawsuit when it bought Texaco in 2001. Texaco started oil exploration activities with Ecuador’s state oil company Petroecuador back in 1964, and for the next three decades, the 47 plaintiffs say, the company contributed to dumping billions of gallons of waste oil in the region, causing loss of livelihood, widespread health problems and up to 1400 deaths. [TIME]
Antarctica’s Lake Vostok–and its potential scientific findings–remains cut off from the outside world for yet another year. Russian scientists spent the Antarctic summer drilling towards the water in the frozen-over Antarctic lake, but plummeting temperatures forced them to leave earlier this week, as their airplane’s hydraulic fluid was in danger of freezing.
The Russians may have flown off, but they left some controversy behind. To keep the 12,300-foot-deep borehole from filling with ice the researchers loaded it full of kerosene, and some Antarctic experts are worried that the chemicals will contaminate an otherwise pristine place.
The 6,200-square-mile lake is important for scientists because the iced-over waters have been isolated for over 14 million years. Biologists are excited to see whether it holds ancient microbes; climatologists are interested in the record held in its sediments; and geologists want to learn how such an isolated sub-glacial lake forms. And despite this year’s setback, researchers are surprisingly unfazed:
Up to 16.6 million people in the United States may be drinking water laced with a chemical found in rocket propellants and fireworks. It’s called perchlorate, and although the Bush administration decided against regulating it, the Obama administration’s EPA has reversed course and announced plans to set a limit for the amount of perchlorate drinking water can contain.
Research by the Food and Drug Administration, among others, found perchlorate contamination in food and water in 45 states, and a small study in the Boston area found perchlorate in the breast milk of nursing mothers. [Los Angeles Times]
While the chemical is found nationwide, it’s particularly a problem in California, near the state’s old manufacturing sites and military bases. Before companies wised up, it used to be common practice to dump perchlorate into unlined pits which–surprise!–leads to the chemical seeping into groundwater. This water eventually finds its way into many places, including public drinking water supplies and irrigation systems.
Because that water irrigates crops and rangeland, perchlorate also taints a variety of foods. A U.S. Food and Drug Administration study of raw and prepared foods in 2006 found elevated perchlorate levels in everything from ice cream and chocolate bars to raisins and spinach…. Its presence in baby cereal and formula — and breast milk — is particularly worrisome given perchlorate’s impacts on the thyroid gland. Chronic exposure to perchlorate can dampen the thyroid’s ability to absorb iodide and produce hormones. That, in turn, can disrupt metabolic functions in adults and impede physical and mental development in unborn children and infants. [San Francisco Chronicle]
The oil stopped spilling from the Deepwater Horizon wellhead months ago, but the Gulf of Mexico’s environmental saga continues. Researchers have investigated the chemicals used to disperse the oil flow in the first place, and found that these “dispersants” didn’t disperse. The effects of this massive chemistry experiment, however, are still unknown.
“The dispersants got stuck in deep water layers around 3,000 feet [915 meters] and below,” said study leader David Valentine, a microbial geochemist at the University of California, Santa Barbara…. “We were seeing it three months after the well had been capped. We found that all of that dispersant added at depth stayed in the deepwater plumes. Not only did it stay, but it didn’t get rapidly biodegraded as many people had predicted.” [National Geographic]
In total, the response team pumped over 800,000 gallons of dispersants into the oil flow; dispersants break down oil into smaller droplets that can degrade more quickly. But the impact of the dispersants themselves has been up for debate. For the new study, scientists tracked the dispersants by following one of its ingredients: dioctyl sodium sulfosuccinate (DOSS).
The Permian extinction event was the biggest shake-up of life that Earth has ever seen: in the “Great Dying” that took place 250 million years ago, more than 90 percent of marine species were killed and about 70 percent of land animals vanished. The cause of this catastrophe has been debated for years, but new research suggests that volcanic eruptions triggered massive coal fires that pumped pollution into the air, eventually poisoning the planet.
The study, published in Nature Geoscience, is based on new findings from arctic rocks that date back to the Permian period, when all of the planet’s land masses formed a supercontinent called Pangaea. When the researchers analyzed the rocks, they found signs of a coal-based apocalypse.
Besides the usual miniscule clumps of organic matter, they also found tiny bubble-filled particles called cenospheres. These frothy little blobs form only when molten coal spews into the atmosphere, the researchers say…. [The cenospheres] must have been created when massive amounts of molten rock—more than 1 trillion metric tons—erupted through overlying coal deposits in Siberia to form lava deposits known as the Siberian Traps. [ScienceNOW]
Coal ash: Two years after the coal ash spill in Roane County, Tennessee residents are still grappling with ash dust, housing buyouts, and potentially toxic water. The Tennessee Valley Authority, a government-owned corporation who runs the plant, claims the ash is non-toxic, while the EPA takes it’s time deciding if it should be classified as hazardous waste.
Wolves: Activist group Center For Biological Diversity is planning to sue the Department of the Interior if they don’t expand wolf ranges in the lower 48. Some states in the Northern Rocky Mountains, where the population has made a comeback, have legalized hunting to protect their herds.
Elephant genomes: New genetics data is showing that the African elephant is actually two species: the forest elephant is smaller than the savanna elephant and has a much smaller population. Dividing the “African elephant” into two species is going to be important to conservation of the forest elephant’s habitat and save them from poachers.
It’s no surprise that a chemical as potent as methylmercury harms wildlife when it enters an ecosystem in high concentration. In the case of wetland birds, researchers have found, it can even change sexual orientation, causing males to pair off with other males.
“We knew mercury could depress their testosterone (male sex hormone) levels,” explained Dr Peter Frederick from the University of Florida, who led the study. “But we didn’t expect this.” [BBC News]
Frederick and Nilmini Jayasena examined white ibises from South Florida for their study in the Proceedings of the Royal Society B. They gathered 160 of the birds and broke them up into four groups that ate food laced with different concentrations of methylmercury. Some ate 0.3 parts per million of mercury, some 0.1, some 0.05, and some none at all.
Birds exposed to any mercury displayed courtship behaviour less often than controls and were also less likely to be approached by females when they did. As the level of mercury exposure increased, so did the degree and persistence of homosexual pairing. Males that engaged in homosexual parings were also less likely to switch partners from year to year, which Frederick says ibises tend to do if they have been unsuccessful in mating during their first breeding season. [Nature]