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Where I grew up in Tennessee, a coal-fired power plant perches by the river, just down from the bridge that my wild brothers and their friends would jump off in the summer. Despite the proximity, I never thought too much about the power plant and the energy it was churning out.

But then I read an April 3 Nature Energy paper on coal-fired energy production that used my town — and others in the Tennessee Valley Authority area — as a natural experiment. The story the data tell is simultaneously fascinating and frustrating, and arrives at a politically prescient time. In recent weeks, the Trump administration has signaled a shift in energy policy back toward the fossil fuel.

The roots of this story were planted in the 1930s, when the TVA was created as a New Deal project to help haul America out of the Great Depression. The organization soon got into the power business, relying on a mix of energy sources: hydropower, coal and nuclear. After the 1979 accident at Three Mile Island — a nuclear power plant in Pennsylvania — stricter regulations driven by public fear prompted TVA to shut down its two nuclear reactors. Those temporary closures in 1985 left a gaping hole in the region’s energy production, a need immediately filled by coal.

Economist Edson Severnini realized that this dramatic shift from nuclear to coal offered a chance to study the effects of coal-fired power on health. He analyzed power production, particle pollution and medical records of babies born near coal plants. One in particular picked up the most slack: Paradise Fossil Plant in Paradise, Ky. (Incidentally, that town is the same coal-ravaged one John Prine sings about in arguably the best song ever written.) The plant’s power production increased by about 27 percent, replacing about a quarter of the missing nuclear energy.

Not surprisingly, air pollution near the Paradise plant rose, Severnini found. The levels of an air pollution indicator called total suspended particulate fell below the Environmental Protection Agency’s limit at the time (but wouldn’t have passed today’s tougher standards, Severnini says). Still, babies born near the plant in the 18 months after the nuclear shutdowns in 1985 were about 5 percent smaller than babies born in the 18 months before. No difference in birth weight showed up in babies born near other power plants that didn’t change their output (including my town’s).
That 5 percent difference was “really, really surprising,” says Severnini, of Carnegie Mellon University in Pittsburgh. Studies have linked low birth weight to trouble later in life, including a lower IQ, lower earnings and health problems, particularly heart disease.
UCLA environmental epidemiologist Beate Ritz puts that 5 percent drop in context. “These coal-fired power plants coming online can be compared with a pregnant woman smoking one pack of cigarettes a day,” she says. “That’s pretty bad.”

Ritz, who studies the hazards of air pollution in Los Angeles, points out that it’s not just the lowest birth weight babies affected. The whole curve of birth weights shifted, so that in all likelihood, most babies born there were impacted in some way. “There’s only a small percent in the upper end of the curve that is unaffected,” she says. “Everybody else has probably some kind of subtle effect that you can’t measure on their brain development, on their lung development, on their immune system.”

The study compares nuclear energy to coal. But the issue is far more complex than that, Severnini says. He hopes the example he found will serve as a reminder of how all energy decisions come with complex trade-offs. “Any energy production choice we make has costs and benefits, and we need to weigh them fully.”

The TVA case study fits with many other examples of how coal pollution can harm health, says Bernard Goldstein, a physician and environmental public health expert at University of Pittsburgh. “We should get rid of particulates, and coal contributes to that,” he says.

U.S. dependence on coal is ebbing, in part because natural gas is cheap right now. But coal isn’t dead yet. “My administration is putting an end to the war on coal,” President Donald Trump said March 28, before he signed an executive order that lifted the ban on coal leases on federal land. He also aims to lift other restrictions that affect the coal industry. It’s not yet clear how — or whether —those policies will be enacted, or whether they’ll be enough to revive the coal industry. (Tellingly, the Paradise plant plans to shut down two of its three coal-burning units as it shifts to natural gas.)

“If the president gets his way, this would slow [coal’s descent] down,” says Goldstein, who coauthored a March 23 New England Journal of Medicine opinion piece on why the Trump administration should pay attention to environmental science. Goldstein likens the situation to government efforts to discourage teenage smoking, a trend that’s also decreasing. Just because the numbers are already falling doesn’t mean we shouldn’t hasten that drop, he says.

And unlike exposure to other pollutants like cigarette smoke, air isn’t optional. “You don’t have a choice,” Ritz notes. We are all breathing the air that’s around us, whether we are in Paradise or not.

PHILADELPHIA — If you want to beat them, join them. Some breast cancer tumors may follow that strategy to spread through the body.

Breast cancer tumors can fuse with blood vessel cells, allowing clumps of cancer cells to break away from the main tumor and ride the bloodstream to other locations in the body, suggests preliminary research. Cell biologist Vanesa Silvestri of Johns Hopkins University School of Medicine presented the early work December 4 at the American Society for Cell Biology/European Molecular Biology Organization meeting.

Previous research has shown that cancer cells traveling in clusters have a better chance of spreading than loners do (SN: 1/10/15, p. 9). But how clusters of cells get into the bloodstream in the first place has been a mystery, in part because scientists couldn’t easily see inside tumors to find out.

So Silvestri and colleagues devised a see-through synthetic version of a blood vessel. The vessel ran through a transparent gel studded with tiny breast cancer tumors. A camera attached to a microscope allowed the researchers to record the tumors invading the artificial blood vessel. Sometimes the tumors pinched the blood vessel, eventually sealing it off. But in at least one case, a small tumor merged with the cells lining the faux blood vessel. Then tiny clumps of cancer cells broke away from the tumor and floated away in the fluid flowing through the capillary. More work is needed to confirm that the same process happens in the body, Silvestri said.

Termites are the new cockroach.

Literally. The Entomological Society of America is updating its master list of insect names to reflect decades of genetic and other evidence that termites belong in the cockroach order, called Blattodea.

As of February 15, “it’s official … that termites no longer have their own order,” says Mike Merchant of Texas A&M University in College Station, chair of the organization’s common names committee. Now all termites on the list are being recategorized.
The demotion brings to mind Pluto getting kicked off the roster of planets, says termite biologist Paul Eggleton of the Natural History Museum in London. He does not, however, expect a galactic outpouring of heartbreak and protest over the termite downgrade. Among specialists, discussions of termites as a form of roaches go back at least to 1934, when researchers reported that several groups of microbes that digest wood in termite guts live in some wood-eating cockroaches too.

Once biologists figured out how to use DNA to work out genealogical relationships, evidence began to grow that termites had evolved as a branch on the many-limbed family tree of cockroaches. In 2007, Eggleton and two museum colleagues used genetic evidence from an unusually broad sampling of species to publish a new tree of these insects (SN: 5/19/07, p. 318). Titled “Death of an order,” the study placed termites on the tree near a Cryptocercus cockroach.

Cryptocercus roaches live in almost termitelike style in the Appalachian Mountains, not too far from chemical ecologist and cockroach fan Coby Schal at North Carolina State University in Raleigh. Monogamous pairs of Cryptocercus roaches eat tunnels in wood and raise young there. The offspring feed on anal secretions from their parents, which provide both nutrition and starter doses of the wood-digesting gut microbes that will eventually let the youngsters eat their way into homes of their own.
Termites are “nothing but social cockroaches,” Schal says. Various roaches have some form of social life, but termites go to extremes. They’re eusocial, with just a few individuals in colonies doing all of the reproducing. In extreme examples, Macrotermes colonies can grow to 3 million individuals with only one queen and one king.

After several years of debate, the common names committee of the American entomologists’ organization voted it was time to switch to the new view of termites. At a February meeting of the society board, there was no objection. The common names of individual termite species, of course, will remain as something-something “termite.”

Considering whether to demote a whole order of insects is an uncommon problem, says Whitney Cranshaw of Colorado State University in Fort Collins, a longtime member of the society’s naming committee. “Probably some of us, including myself, didn’t want to make the change because we liked it the way it was,” he says. Termites and cockroaches as separate orders were easy to memorize for the undergraduates he teaches. Yet, he voted yes. “It’s what’s right.”

Two human mummies housed at the British Museum in London for more than a century boast the world’s oldest known — and longest hidden — tattoos of figures and designs, a new investigation finds. These people lived in Egypt at or shortly before the rise of the first pharaoh around 5,100 years ago.

Radiocarbon analyses of hairs from the mummies date the bodies to between 3351 B.C. and 3017 B.C., says a team led by Egyptologist Renée Friedman of the University of Oxford and bioarchaeologist Daniel Antoine of the British Museum in London. Infrared photography revealed that smudges on a male mummy’s upper right arm depict a wild bull and a Barbary sheep, while a female mummy bears four S-shaped patterns on her right shoulder and a line with bent ends on her right arm. These animals and figures appear in Egyptian art from the same period, the researchers report online March 1 in the Journal of Archaeological Science. Both sets of tattoos — which consist of a carbon-based pigment, possibly soot — may have symbolized power, social status or knowledge of cult activities, but their precise meanings are unclear.
The two were the only mummies found with tattoos, out of seven mummies originally buried at a southern Egyptian site and now held at the British Museum. All of the bodies had been preserved by the desert’s dry heat.

The tattooed Egyptian mummies are approximately as old as Ötzi the Iceman. The mummified man found in the Italian Alps has 61 dark lines tattooed on his limbs and torso, but no pictures or designs (SN: 1/23/16, p. 5). Some of the Iceman’s tattoos covered areas of joint disease and may have been intended as treatments. CT scans of the two Egyptian mummies found no signs of bone disease near or below tattoos.