Deirdre Lockwood

Sanchi oil spill continues; impacts still unclear

Rough seas have begun to disperse oil spilled from a sunken tanker in the East China Sea. The spill’s total surface area has fluctuated in the past week from a high of 332 km2 on Jan. 21 to a report of 93 km2 on Jan. 25, according to China’s State Oceanic Administration. The Iranian tanker Sanchisank on Jan. 14 after colliding with a Chinese cargo ship and burning for over a week. It may be leaking heavy bunker fuel that was powering the vessel in addition to some of the 136,000 metric tons of ultralight crude oil, called condensate, that it was carrying. Undersea robots have detected a 35-m-wide triangular hole in the vessel, according to China’s Ministry of Transport. However, attempts to plug the hole or recover oil from the ship may be challenging because the condensate is highly flammable and explosive, and a weather system is expected to

Seed extract helps remove bacteria from water

Researchers have designed a simple drinking water filtration method using sand combined with a protein extract from the seeds of the Moringa oleifera tree, common in equatorial regions. Moringa seeds contain positively charged, water-soluble proteins that have been found to attract particles and kill bacteria. Stephanie Butler Velegol and Manish Kumar of Pennsylvania State University and their colleagues suspended ground-up Moringa seeds in water and then combined the liquid extract with sand. The researchers packed the sand into filter columns about 1 cm in diameter by 5–10 cm high and carried out tests to optimize the columns’ performance. The filters completely removed Escherichia coli from water in which the concentration of the bacteria was more than 100,000 times as great as that in typical wastewater samples (Environ. Sci. Technol. Lett. 2017, DOI: 10.1021/acs.estlett.7b00490). The researchers aim to develop the design into an easy, inexpensive, and sustainable way for households and

Is grad school for you

One night during my junior year of college, I stayed late in my adviser’s biochemistry lab to run some kinetics experiments on catalytic antibodies—data that would become part of my senior thesis. I was so absorbed that I didn’t notice at first when my adviser poked her head in. “You would make a great graduate student,” she said with a smile. She was putting her finger on something I’ve heard from many people since then: If you’re trying to decide whether to apply to graduate school in the chemical sciences, the most important question to ask yourself is whether you enjoy scientific research and problem solving. That’s because the core of a graduate program in science is taking on a research project of your own. By the end of it, you’ll probably know more than your adviser about your chosen focus. As the director of the graduate program I eventually

Photocatalyst shreds PFOA

A new photocatalyst could help clean up the industrial pollutant perfluorooctanoic acid (PFOA), which contaminates drinking water in many parts of the U.S. (Environ. Sci. Technol. Lett. 2018, DOI: 10.1021/acs.estlett.8b00395). PFOA and another common perfluorinated contaminant, perfluorooctane sulfonate (PFOS), were once used to make products like Teflon, Scotchgard, and firefighting foams, and may threaten human health through chronic exposure at the parts-per-trillion level. These are “among the most recalcitrant pollutants ever produced,” says Timothy Strathmann of the Colorado School of Mines, who was not involved in developing the new catalyst. Granular activated carbon is most often used to remove them from water, but naturally present organic matter sticks irreversibly to the carbon, using up its capacity to grab the pollutants. Ezra L. Cates of Clemson University develops semiconductor particles that are excited by UV radiation and act as photocatalysts to degrade the compounds. Cates and his coll...

Can shellfish adapt to ocean acidification

If you’re an oyster aficionado living in the Pacific Northwest, you’ve likely tasted Chris Langdon’s scientific handiwork. Since 1996, his Molluscan Broodstock Program at Oregon State University has been breeding plump, fast-growing, and hardy oysters as stock for the

Could a pill one day reverse some of the damage lead inflicts on the brain

250 million West Coast oyster industry. But in the past several years, the program has taken on an additional goal: identifying and studying oysters that may be better prepared to thrive in an increasingly acidified ocean. In 2007, oyster hatcheries in Oregon and Washington began experiencing massive die-offs of their larvae that continued for several years. Eventually, managers and scientists realized that the larvae were dying during periods of strong upwelling, when deep waters rich in CO2—and low in pH—come to the surface. These deep waters were even more acidified than in the past because of the oceans’ increasing uptake of CO2 from an atmosphere where levels of the greenhouse gas

Water-splitting step proceeds 100% efficiently

A naturally derived small molecule reverses some of lead’s harmful effects in the brains of rats, a new study shows. The finding could be an early step toward a potential therapy for children with lead poisoning, researchers say (Toxicol. Sci. 2017, DOI: 10.1093/toxsci/kfx210). “Worldwide, millions of children are exposed to lead,” says Tomas Guilarte of Florida International University. The toxic metal can be especially harmful to children’s developing brains. “The first thing in public health is prevention, but that’s almost impossible in many parts of the U.S. and the world,” he says. So he and his team have been investigating possible ways to repair some of the inevitable damage. One way lead damages the brain is by disrupting the junctions between nerve cells, known as synapses. Guilarte and colleagues discovered that lead does this by first inhibiting the N-methyl-D-aspartate receptor (NMDA), which is highly expressed in the hippocampus, a brain

Fracking waste can persist for years

Researchers have set a record for part of the process of using sunlight to split water, reporting 100% efficiency for the half-reaction that evolves hydrogen, a clean-burning fuel (Nano Lett. 2016, DOI: 10.1021/acs.nanolett.5b04813). One factor limiting the efficiency of water splitting is the tendency of excited electrons and positive charges generated during light absorption to rapidly recombine. The electrons are needed to reduce protons to molecular hydrogen. So Lilac Amirav of Technion—Israel Institute of Technology and her colleagues designed a nanoparticle-based photocatalyst that keeps the charges separated. They created a light-harvesting cadmium sulfide quantum rod with a quantum dot of cadmium selenide embedded near one end and a platinum tip on the other. When suspended in water and exposed to visible light, the CdS quantum rod absorbs photons, releasing electrons. The rod transfers electrons to the platinum tip, reducing protons to hydrogen and leaving behind positively charged holes in the

POPs persist in the deep blue sea

In North Dakota’s Bakken region, a boom of hydraulic fracturing, or fracking, has generated nearly 10,000 wells for unconventional oil and gas production. This increased production also has resulted in almost 4,000 reported spills of fracking wastewater. According to a new study, these spills have left soil and surface water in the area contaminated with water carrying radium, selenium, thallium, lead, and other toxic chemicals that can persist for years at unsafe levels (Environ. Sci. Technol. 2016, DOI: 10.1021/acs.est.5b06349). Using fracking in oil and gas production brings up a brine that carries naturally occurring toxic or radioactive elements such as radium and selenium from rock formations. To understand the impact of fracking wastewater spills on the environment, Avner Vengosh of Duke University and his colleagues sampled water, sediment, and soil at sites of reported brine spills, which had occurred months to years earlier. To trace the source of contaminants at

Controversy Clouds E-Cigarettes

An alphabet soup of persistent organic pollutants—including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs)—is carried by the wind and rivers into the ocean. A new study bolsters findings from scant prior sampling showing that these compounds riding on ocean currents have penetrated as far as 2,500 meters deep in the Atlantic Ocean (Environ. Sci. Technol. 2016, DOI: 10.1021/acs.est.5b05891). Rainer Lohmann of the University of Rhode Island and colleagues deployed samplers at various depths at mooring sites in the North Atlantic and in the tropical Atlantic to measure organic pollutants dissolved in the water. The samplers contained polyethylene films that sorb dissolved organic contaminants. After a year, the researchers collected the films, extracted the compounds, and analyzed them using gas chromatography-mass spectrometry, searching for 78 target pollutants that included PCBs, PBDEs, and PAHs. The deep ocean is “clearly not highly p...