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This year is the International Year of Soils, so designated by the United Nations. Don’t worry if you didn’t know that. Many people don’t think about soil, or even know what it’s made up of or how its inhabitants are vital to its health—and by extension to our survival. What Leonardo da Vinci said some 500 years ago is still true today: “We know more about the movement of celestial bodies than about the soil underfoot.” Of course, scientists have since learned something about Earth’s epidermis. They have classified thousands of soil types by their mineral compositions and now know that soils are full of bacteria, fungi, protozoans, nematodes, insects, and the random mole, gopher tortoise, or burrowing owl. But less well understood is how soils are processed and remodeled by an often-overlooked subterranean chemical engineer: the earthworm. Researchers are still trying to fully understand the outsized role earthworms play ...

Sugar is toxic. The fat and sodium we’ve spent so much time fretting over may in fact be the lesser of the evils in our diet. New evidence suggests that sugar—and possibly artificial sweeteners—might be the ultimate cause of high blood pressure, high cholesterol, heart disease, diabetes, and liver disease. Natural sugars in our diet aren’t the ones on trial here. It’s added sugars that are under greater scrutiny than ever before. Former New York City Mayor Michael R. Bloomberg’s 2012 effort to curb the sale of supersized soft drinks put a spotlight on the added sugars in soda. But added sugars are prevalent in many foods and beverages: coffee and sports drinks, juices, grain-based desserts, candy, and ready-to-eat cereals. Naturally, the food and beverage industries—and the sweetener purveyors who supply them—officially disagree with sugar’s bad rap. That position hasn’t changed in 40 years. But they are increasingly looking for ...

This year marks the end of a program launched by the Environmental Protection Agency to eliminate the production and use of one of the chemical industry’s most important classes of compounds: perfluorooctanoic acid (PFOA), along with its precursors and analogs. The program, launched in 2006, was prompted by years of pressure by environmental and consumer groups and regulatory scrutiny of the safety of the long-alkyl-chain fluorocarbons, which are used to treat the surfaces of metals, paper, carpet, and fabrics to impart water-, soil-, and oil-repellent properties. They are also used to make abrasion-, chemical-, and fire-resistant polymers and are found in products as diverse as nonstick cookware, grease-wicking pizza boxes, airplane hydraulic fluid, stain-resistant carpet, and breathable rain jackets. Unfortunately, the properties that make the compounds so useful also make them persistent in the environment. The chemicals and their degradation products are now found in places ranging from pristine areas ...

Metals are ubiquitous in our lives. There are the metal objects we can see—paper clips, kitchen utensils, electronics, cars or bicycles, wires and pipes, lightbulbs, hammers and shovels. Most of th...

“All the pests that out of Earth arise, the Earth itself the antidote supplies.” This line, from a poem attributed to Lithica circa 400 B.C., is a prescription that is increasingly guiding 21st-century scientists who develop fungicides, insecticides, and herbicides for crop protection. At the recent American Chemical Society national meeting in Philadelphia, chemists discussed the trend of using natural products to replace synthetic chemicals in pest management. In a symposium sponsored by the Division of Agro­chemicals, the attendees shared a sense of excitement in knowing that a plant, soil bacterium, or fungus could supply a molecular solution to thwart a destructive insect or pathogenic microbe threatening to ruin a good harvest. “The chemical templates offered by nature are often unique, and even the most imaginative and technically capable synthetic chemist lacks the structural vision these molecules provide,” observed Stephen J. Cutler, a natural products chemist at the University of ...

There’s a shake-up taking place in fluorine chemistry. Synthetic organic chemists who don’t normally mess with fluorine are stepping in with their toolbox of synthetic methods to broaden the range ...

MOLECULAR MACHINE’S WORKINGS VISUALIZED A fluorescence microscopy method that marks biomolecules with organic dyes made it possible this year to understand the workings of complex biomolecular proc...

IN HIS 2003 State of the Union address, President George W. Bush proclaimed that the time was ripe for the hydrogen economy, a world in which hydrogen is the primary energy currency instead of fossil fuels. He committed $1.2 billion toward research to develop hydrogen fuel-cell technology and the ability to cheaply prepare and store hydrogen to meet transportation needs. Concerns about oil supply, fuel price volatility, and greenhouse gas emissions were going to evaporate. Now, nearly a decade later, a veil of dust has settled over the hype about hydrogen. Officials in the Bush Administration hadn’t promised an overnight success, although the public may have perceived the pronouncements that way. But, as with any disruptive technology, there is a long product development cycle. For hydrogen in particular, the uncertainty over just how long oil will last and competing interests in biofuels and batteries for powering cars stand in the way. Even with ...

WHETHER OR NOT anyone likes the idea of ripping up the landscape of northern Alberta or poking lots of well holes into it to access oil-rich sand deposits, the world—and more specifically the U.S. ...

CHEMISTS, chemical engineers, and synthetic biologists have largely met the technical challenge of developing biofuels to supplement and then replace petroleum-derived transportation fuels in the coming decades. For biofuels to reach the U.S. market, however, these technologies have to fit into the existing transportation fuel infrastructure. Every major chemical and petrochemical firm has claimed a stake in the race to biofuel commercialization, as have dozens of start-up companies. Biofuels have multiple starting points, including sugars, starches, vegetable oil, recycled paper and cardboard, and raw biomass, which can be processed by biological or chemical methods, or both. Whichever ones win, the competing technologies’ versatility ensures that companies will make money, and the country will gain energy security by eliminating dependence on imported oil, as well as climate security by reducing greenhouse gas emissions. “We all know how to get from the beginning to the end and make biofuels—we’ve all d...

When microwave ovens started appearing in chemistry labs in the late 1980s, it wasn’t just to heat up leftovers for lunch or to make popcorn or a frozen burrito for a late-night snack. Imaginative organic chemists had figured out that there’s an advantage to using microwaves to rapidly and uniformly heat reaction mixtures to accelerate synthetic processes. The word quickly spread to materials scientists making nanoparticles, biochemists synthesizing peptides, and environmental scientists preparing samples for chemical analysis. Microwave reactors are now standard equipment throughout the pharmaceutical and chemical industries, as well as in many university organic synthesis and teaching labs. Organic chemists are particularly enamored with microwaves because reactions that take hours of refluxing in a flask sitting in an oil bath at atmospheric pressure can instead be completed in minutes, often with improved yields and product purity. “Process intensification at high temperature and pressure is the essen...

CHEMICAL COMPANIES large and small are eager to become greener. They want to be able to select greener starting materials and use cleaner chemical processes to make environmentally preferred products. But there are no authoritative marketplace criteria to identify green, greener, or greenest. And for those who think they are green, there’s uncertainty over the best way to communicate the supporting information. The solution: Develop a comprehensive voluntary industry standard that enables everyone from raw material suppliers and manufacturers to retail consumers and policymakers to exchange common information in a standard format on the environmental performance of chemical products and processes. Government agencies, nongovernmental organizations, some chemical companies, and large retailers such as Walmart and Carrefour have already set out to develop assessment tools and enhanced metrics to achieve that ideal. But so far, these efforts are specific for individual classes of chemicals or market segments...

NEARLY ALL HUMANS, and a large proportion of wildlife, are contaminated with environmentally persistent long-chain perfluoroalkyl compounds. That revelation, around for a decade now, has brought dr...

WHETHER OR NOT global warming stemming from human activities is occurring is developing into the great scientific debate of our time. If it’s true, the larger questions are what the climate consequences will be and whether or not there is anything anyone can do about it. Policymakers meeting in Copenhagen just wrapped up two weeks of discussions driven by those questions. At C&EN press time, they had failed to agree on an international treaty to control greenhouse gas emissions in an effort to stave off global warming while preserving current standards of living. An underlying cause that seems to be holding everything up is a renewed upwelling of uncertainty in the science behind the debate. Mainstream climate scientists maintain that man-made global warming is happening. But a few global-warming skeptics argue that there is still a lot of guesswork in how those scientists came to that conclusion. At the root of the for-and-against arguments is ...

PHASE-SWITCHING CATALYSIS By simply adding or removing carbon dioxide, chemists in Scotland devised a neat trick for reversibly shuttling a homogeneous catalyst between the organic and aqueous phases in a biphasic solvent system (CE Angew. Chem. Int. Ed. 2009, 48 , 1472). The phase-switchable catalyst designed by Simon L. Desset and David J. Cole-Hamilton of the University of St. Andrews adds flexibility to the often complicated techniques required to isolate products and recycle catalysts during homogeneous reactions. The secret to the switchability is a weakly basic amidine group, –N=C(CH 3 )N(CH 3 ) 2 , that the researchers added to the phenyl rings of triphenylphosphine. The rhodium catalyst made with the modified phosphine ligand is soluble in organic solvent. On bubbling CO 2 into an aqueous-organic reaction system containing the catalyst, the CO 2 reacts with water to form carbonic acid (H 2 CO 3 ). The transient acid protonates the amidine groups and renders the catalyst water...

HYDROGEN BONDING has evolved from being a curious intermolecular interaction between a hydrogen atom and an electron-rich partner to being a powerful tool for crystal engineering of solid-state materials and for molecular control of protein and DNA chemistry. Now, chemists are making progress in understanding and harnessing halogen bonding, a similar phenomenon pairing a halogen atom with an electron-rich partner. The nature of halogen bonding and its practical applications were discussed at last month’s ACS national meeting in Washington, D.C., during a symposium cosponsored by the Divisions of Organic Chemistry and Fluorine Chemistry on “Halogen Bonding: A World Parallel to Hydrogen Bonding.” According to symposium co-organizers Pierangelo Metrangolo and Giuseppe Resnati of Polytecnico di Milano, in Italy, the event was the first international meeting fully devoted to halogen bonding. The aim of the symposium was to “draw the attention of the global scientific community to the huge and largely unexplore...

KILLER WHALES, clean white socks, and race cars aren’t exactly what people associate with green chemistry. Yet they were among many compelling topics on the agenda at the 13th Annual Green Chemistry & Engineering Conference (GC&E), held on June 23–25, in College Park, Md. That green chemistry has permeated such a miscellaneous mix of topics suggests that it is no longer just the bold new idea that it was when a few scientists at the Environmental Protection Agency first formalized the concept nearly 20 years ago. Rather, it indicates that green chemistry has matured as a design framework and is now helping chemists and chemical engineers of all stripes to develop better chemical processes and products across-the-board. “The tag line green chemists and engineers are now using is cleaner, cheaper, smarter chemistry,” pointed out GC&E Chair Liz U. Gron, an analytical chemist at Hendrix College, in Conway, Ark. “That is exactly what we need in ...

COULD METALS become extinct? That question has popped up in magazine articles and in the blogosphere in response to predictions by several scientists—taken out of context—that some metals running u...

AD HOC EFFORTS by an impressive array of federal and state agencies, farmer alliances, chemical companies, and nonprofit advocacy groups are dramatically shifting the way pesticides are made and us...

1 SURPRISE FROM S N 2 SNAPSHOTS By analyzing snapshots of single-molecule collisions, an international research team uncovered unanticipated details about the mechanism of the classic bimolecular nucleophilic substitution (S N 2) reaction (CE Science 2008, 319 , 183). In addition to providing direct evidence for the traditional S N 2 mechanism in the gas phase, Roland Wester and colleagues at the University of Freiburg, in Germany, together with William L. Hase and colleagues at Texas Tech University detected an additional unexpected pathway. In this “roundabout mechanism” the nucleophile bumps into the substrate, spinning the substrate 360° before substitution and leaving-group displacement occur. To visualize these details, the Freiburg team crossed beams of reactants in a vacuum and detected the directional and speed distributions of the products. The data suggested at least two reaction mechanisms, one of which is the traditional S N 2 pathway. Atomic-level chemical dynamics simula...

THE DEPARTMENT of Energy estimates that about 1 billion dry tons of cellulosic biomass per year in the U.S. could be converted into biofuels. This estimate is a limit of how much plant material fue...

THE PHARMACEUTICAL industry is making great strides in developing cleaner and more efficient syntheses—that is, greener chemistry—for manufacturing small-molecule drugs. But how green are manufacturing processes for biopharmaceuticals, such as monoclonal antibodies, peptide hormones, and vaccines? And can those processes be greener? Those are questions Sa V. Ho and colleagues at Pfizer’s Global Biologics unit, based in Chesterfield, Mo., are trying to answer. The researchers have set out to determine the type and amount of resources required and the wastes generated by mammalian-cell-culture and microbial fermentation processes that are used to make therapeutic proteins. Their goal is to promote cost-saving process improvements that are also environmentally friendly. In doing so, they hope to stimulate other pharmaceutical companies to join them in developing metrics that illuminate the degree of greenness in biologics manufacturing processes, Ho says. The pharmaceutical industry is one of the first major...

WHEN IT COMES TO green chemistry, big numbers are a big deal. Consider 145 million lb of hazardous chemicals and solvents eliminated from industrial use each year. That's enough material to fill almost 700 railroad tank cars, which would make up a train nearly 9 miles long. Or how about 55 million gal of water saved each year, which adds up to the amount of water used by 2,100 people. Then there's 57 million lb of carbon dioxide no longer released to the atmosphere each year, the equivalent of taking 6,000 cars off the road. These numbers represent the savings of the 57 groundbreaking technologies that have received Presidential Green Chemistry Challenge Awards since the program's inception in 1995. Richard Engler, director of the Environmental Protection Agency's Green Chemistry Program, which administers the awards, takes some pride in keeping track of those statistics. "Through 2006, Challenge winners have made nearly 750 million lb of progress," ...

CARBON DIOXIDE is nontoxic, nonflammable, and essentially free for the taking. Those attributes make it sound like CO 2 could be a great feedstock for making commodity chemicals, fuels, and materials—and it already is playing that role for a few applications. But there are a few catches. One is that CO 2 is very stable, which means it takes extra effort to activate the molecule so it will react. Another reality check is that so much of the unwanted greenhouse gas is escaping into the atmosphere as a consequence of burning fossil fuels that even shunting millions of tons of it each year into making chemicals won't have much of a bearing on the gas's global warming threat. So what's one to do with CO 2 ? C&EN asked that question of a number of chemists and chemical engineers. These investigators were unanimous on the scope of the CO 2 problem. They understand that technology to capture ...

"SOMETIMES IT SEEMS to me that a bond between two atoms has become so real, so tangible, so friendly, that I can almost see it. Then I awake with a little shock, for a chemical bond is not a real thing. It does not exist. No one has ever seen one. No one ever can. It is a figment of our own imagination. This quote conveys the words of Charles A. Coulson, a prominent theoretical chemist at the University of Oxford, who influenced a generation of chemical-bonding enthusiasts from the 1940s to the early 1970s. Chemistry Nobel Laureate Roald Hoffmann of Cornell University likes to recite Coulson's comments from the early 1950s as part of his own lectures on chemical bonding.Hoffmann knows something of bonding, having devoted much of his career to being intimate with molecular orbitals. With Robert B. Woodward at Harvard University in the early 1960s, Hoffmann helped ...

CHEMICAL ENGINEERING as a discipline is in a unique position. The field is sufficiently large and diverse enough to reach across and have a significant impact on abroad range of technologies, yet small enough for its practitioners to maintain the sense of a close-knit community. How long this delicate dichotomy will hold is hard to say. But the collegiality of chemical engineers was evident during the recent annual meeting of the American Institute of Chemical Engineers (AIChE) held on Nov. 12-17 in San Francisco. "This conference is like no other," commented John G. Chen, AIChE president and a chemical engineering professor at Lehigh University, Bethlehem, Pa. "We have more than 4,500 chemical engineers from academia, industry, and the public sector all together to discuss the cuttingedge and important aspects of chemical engineering." "The AIChE meeting always provides a unique insight into the important challenges that chemical engineering researchers are facing," noted Martin A. Abraham, a ...

ONCE UPON A TIME , journal covers were a dry landscape that simply gave boilerplate information and served as a wrapper for the important science reported inside. Technology advances in both graphic design and printing have gone a long way in changing that landscape in the past decade, as nearly every chemistry journal now includes full-color graphical elements on the cover. Having a paper featured on a journal cover offers such increased visibility for the work that some researchers may try to influence the selection process by creating a special graphic or using the art of self-promotion. But chemistryjournal editors, as well as the editors of premier general science journals such as Science, Nature, and Proceedings of the National Academy of Sciences USA, are accustomed to the ploys and pleas of researchers seeking to win a coveted cover and instead let the peer review process be their guide. In addition, just ...

IT'S RARE FOR A SCIENTIST to develop a new theory and then 50 years later have the opportunity to step back and view its impact—let alone make two such outstanding discoveries. But that's the story of chemistry professor Rudolph A. Marcus of California Institute of Technology, who was instrumental in developing electrontransfer theory and the RRKM unimolecular reaction-rate theory. Marcus and his two theories were the center of attention last month at a four-day symposium sponsored by the Division of Physical Chemistry during the American Chemical Society national meeting in San Francisco. In 1956, Marcus published a pair of papers outlining the necessary thermodynamics and kinetics of electron-transfer reactions in chemical systems. The papers led to further research on electron transfer over the ensuing nine years, which allowed Marcus to generate a body of work that garnered him the 1992 Nobel Prize in Chemistry. It turns out that these electron-transfer ...

FOR MORE THAN A DECADE, PROponents of green chemistry and green engineering have delivered the message that cleaning up chemical reactions and products is not only good for the environment but also...

SCIENTISTS FROM 12 MIDDLE Eastern nations, including Israel and the Palestinian Authority, met on neutral territory in the Mediterranean island nation of Malta in early November for the second conference designed to forge stronger relationships among scientists in the region. The conference organizers designed the meeting to draw the attention of national governments to the fact that improving regional scientific cooperation could aid sustainable economic development and promote peace and political reconciliation. "We can't leave the peace process in the Middle East only to the politicians," commented chemistry professor Zafra M. Lerman of Columbia College Chicago. Spreading the message that everyone can work together "is the best thing we can do for the Middle East," she told C&EN. Lerman served as chair of the conference organizing committee and leads the American Chemical Society's Committee on Scientific Freedom & Human Rights. Titled "Frontiers of Chemical Sciences II: Research & Education in ...

MOST PEOPLE IN THE DEVELOPED WORLD TAKE FOOD for granted. If you need groceries, you go to the supermarket. Don't feel like cooking? You might order a pizza or Chinese takeout. In a hurry? You're l...

T HREE HUNDRED YEARS AGO, ADventurous scientists working in the fledgling discipline of chemistry often weren't sure what theywould get when cooking up a recipe. That was how Prussian blue was born...

FLUORINE CHEMISTS ARE FOND OF pointing out that even though "their" element has one of the smallest atomic radii on the periodic table, it still has the greatest ability to attract electrons. These properties give fluorine the distinction of being called a lot of names, such as "the small atom with a big ego" or "the little atom that could." Another apt description that fluorine chemists have more recently added to their lexicon is that fluorine is ubiquitous. Fluorine indeed has made major inroads in chemistry, moving beyond commonplace fluoropolymers to become important in other aspects of materials science and to function as an important substituent in agricultural chemicals and active pharmaceutical ingredients. According to University of Southern California chemistry professor G. K. Surya Prakash, chair of the 17th Winter Fluorine Conference, the diverse group of scientists from around the globe and the diversity of the lectures and discussions at this year's meeting "clearly affirmed the ...