How hard is that?

October 20, 2014

By Dr. E. Kirsten Peters

A good friend of mine checks each morning on the web for the final “Jeopardy” question. It’s the last question on the taped “Jeopardy” program to be broadcast later that day. I don’t go to movies or follow sports, so I’m often at a loss when it comes to many quiz show questions. But recently I was in a position to answer the “Jeopardy” question because of my early training in geology.

The category of the question I got right was “to ‘dum’ it up.” That means, in Jeopardy-speak, that the answer will have the syllable “dum” in it. The clue mentioned that there is a substance a chemist would call aluminum oxide that’s sometimes used as an abrasive. How could it be named with “dum” in the word?

Aluminum oxide, or Al2O3, is well known to geologists. You likely know aluminum oxide with certain impurities in it as the gemstone sapphire. With somewhat different impurities, the gem is ruby. So if you find a deposit of the right kind of aluminum oxide in the back of beyond, your financial problems could be over.

But most aluminum oxide in the world isn’t gem quality. Instead it’s the mineral corundum. That was the answer to the “Jeopardy” question. I knew the answer because like all geology students and many a rock hound, I learned the names and properties of scores and scores of minerals (and a few gems) when I was young. Call it my misspent youth.

Like sapphire and ruby, corundum is very hard. On the scale geologists use to measure such things, it has a hardness value of nine. Some gemstones are eight on the hardness scale. Diamond – the hardest natural substance in the world – has a hardness value of ten.

Most sandpaper is made of small quartz grains. Quartz has a hardness of seven. That’s generally hard enough for smoothing down a bit of wood. Depending on its exact chemical composition, garnet is a bit harder than quartz, and in a good hardware store you’ll find garnet sandpaper. Corundum is harder still, making it an abrasive for tough jobs.

The Wall Street Journal recently reported that Apple is investing $700 million to give its new iPhone and smartwatches what are termed “sapphire screens.” The idea is that the screen of the phone won’t be scratched as it rattles around in your pocket or purse with your car keys, and the watch face won’t be scratched if you scape it against a wall – even a brick wall.

Mineralogy to the rescue. But don’t ask what proportion of “Jeopardy” clues I can usually solve.

Dr. E. Kirsten Peters was trained as a geologist at Princeton and Harvard Universities. This column is provided as a service of the College of Agricultural, Human and Natural Resource Sciences at Washington State University. See more columns or listen to the Rock Doc’s broadcasts of them at rockdoc.wsu.edu.

By Dr. E. Kirsten Peters

As a kid, I read the Sherlock Holmes stories and the mysteries of Agatha Christie. As an adult, I wrote four mysteries that focused on a Quaker heroine solving crimes she happened across in her religious community. (I published them using my grandmother’s name — Irene Allen — as a pseudonym.) And, as a geologist, I’ve read about real-life criminal investigations that involved samples of sand and soil.

But it wasn’t until I talked with Dr. Nathalie Wall of the chemistry department at Washington State University that I got my head around forensic science that relates to radioactive materials.

“The basic definition of forensics is that it gives you information about the past,” Wall said to me. “The best known type of forensics is the criminal kind.”

Nuclear forensics is the study of radioactive materials found on places like a suspect’s hand. The goal is to develop information about such things as the source of the nuclear material. One part of the research Wall does is to help develop techniques that can be used for prosecution of people linked to illegally transporting or trafficking in radioactive substances.

“A fingerprint belongs to just one person, so it has real importance as evidence,” Wall said. “But you can’t arrest someone just for having a trace amount of uranium on their hands. There is uranium in granite, so a person can pick up trace amounts of it just from handling rocks.”

That’s part of the reason why it can be much more complicated to make a legal case against a person for dealing in radioactive materials than it can be to prove other kinds of criminal cases.

“The cool thing about nuclear chemistry is that radioactive elements come in sets or suites,” Wall told me. “If you find a specific suite of elements of different proportions, you can potentially tell where the material came from and what it’s been used for. So this is the ‘fingerprint’ we look for.”

Wall’s work is in the chemistry of various radioactive elements. She collaborates with people who make sophisticated devices for testing trace samples of materials.

“Just as the TSA may swipe your hand to see if you’ve touched conventional explosives, our goal is to develop tests for trace amounts of radioactive isotopes,” Wall said. “Part of the challenge is to make the tests both accurate and fast.”

Wall got a start in the research world working on nuclear repositories and contaminated sites. Nuclear forensics has been a recent addition to her work.

“From a chemist’s point of view, it’s all the same story,” Wall said.

Wall’s work is part of a broader who-done-it effort that’s important to all of us. I’m glad she and others like her are at work on real-life investigatory techniques that can stop terrorists.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

By Dr. E. Kirsten Peters

By Dr. E. Kirsten Peters

The Michael Crichton book “Jurassic Park” and the movie based on the best-seller presented what might happen if scientists were able to clone extinct dinosaurs, bringing them back to life. While nothing like that is possible at this time — a good thing when you recall the mayhem the dinos caused in the world Crichton conjured up — sometimes scientists surprise themselves in breathing new life into old organisms.

One example of some success in what’s sometimes called “resurrection ecology” comes from a small island that lies off Antarctica. The place is called Signy Island. It’s one of the South Orkney Islands. Signy experiences short summers (during our northern hemisphere winters), but long winters during much of the year characterize the place. The local environment is too harsh to support trees: instead, the land is carpeted by thick beds of moss.

Peter Convey, a scientist with the British Antarctic Survey, has worked on the island for some 25 years. He recently described the carpet of moss to The New York Times.

“It’s just like a big, green, spongy expanse,” he said.

But only the top layer of the moss is a growing mass of vegetation. The deeper layers don’t get sunlight, so they turn brown. In time, they freeze and join the permafrost that is the core of the island. That frozen moss has been building up in place for thousands of years.

In their short summer field seasons, Convey and colleagues have drilled down through the carpet of moss and into the permafrost. In the cores they removed, they found shoots of moss within the permafrost and even down in gravel layers. Generally, plants break down when they become permafrost, but something different seemed to be happening with the moss shoots.

Convey and his co-workers wondered if the ancient moss might be able to grow again.

“It was just kite-flying,” he said of his idea to a reporter from The New York Times.

The researchers took a core of the permafrost and put it near a lamp in a laboratory. They also misted it with water. In just a few weeks, they were rewarded with moss that was generating new, green growth, even from the zone three and a half feet below the surface.

As they have now reported in the journal Current Biology, they analyzed the moss for carbon-14, the radioactive or “hot” form of carbon that decays naturally over time at predictable rate. This gave the researchers a well-established method to test for how old the buried moss was. The moss they revived in the lab was more than 1,500 years old. In other words, it’s been dormant since around the year 500, but was able to spring back to active life when conditions were favorable. A pretty good trick!

But, obviously, it’s a far cry from reviving old moss to reviving animals like dinosaurs. Still, science yields some surprises now and then. Let’s not rule out anything when it comes to resurrection.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

A tale of two stoves

June 7, 2014

By Dr. E. Kirsten Peters

My elderly aunt in Canada recently came into some money. She decided — very generously — to send part of it to each of her nieces and nephews. This gave me the rather wonderful task of deciding how I wanted to spend $1,000 that I had not anticipated receiving. After a bit I decided on a new range for my kitchen. I wouldn’t otherwise buy a new appliance, and by spending the money on a range I will be able to remember my aunt and bless her name each night as I cook supper.

My old range was electric. The oven was a bit slow, but otherwise baked things OK. The burners, however, were constantly problematic. I had replaced them all but still had to suffer with unpredictable and inconsistent heating.

I grew up with a natural gas cook stove and so decided to buy something similar for my house. I like gas because you can see when it’s on, because it cuts off instantly when you turn off the flame, and because I think of natural gas as a pretty clean fuel we can get from domestic sources.

No sooner had I made up my mind about what to do with the unexpected money than my brother Nils explained he plans to change from a gas range to an electric one. (Leave it to siblings to always disagree?)

Nils thinks a lot about climate change and his family’s use of energy. Some of his ideas are at odds with mine, but I’m (mostly) OK with that.

My brother is truly concerned about humankind’s production of greenhouse gases and the climate change we may bring about during the remainder of this century. He wants to eliminate his own household’s greenhouse gas pollution and he’s willing to do some real work to meet that goal. While I’m more concerned about other political issues, I respect Nils’ earnestness and his willingness to think and spend differently because of climate change concerns. He sees the matter as a moral one, and he’s committed to doing what he can to help bring about changes in both his household and his community.

One step for my brother is to switch his appliances from natural gas to electricity. His idea is that if he uses natural gas to do things like cook supper, he’s making carbon dioxide that adds to what’s building up in the global atmosphere. If he uses electricity to do those same tasks, he can — at least in principle — not create greenhouse gases. While he waits to purchase solar panels, for pays the power company extra each month to purchase electricity from wind.

I like to say to my brother that not all his power can come from windmills or solar panels. After all, he uses electricity on calm winter nights when the wind isn’t blowing and the sun isn’t shining. In short, we all need what the utility people call “base load power.” Across the country, that kind of power comes from several different things, but part of it is from natural gas power plants. So, from my perspective, we all of us are “sinners” when it comes to greenhouse gas production, including people who only own electric appliances.

Nils counters that our need for base load power is not a rationale to continue business as usual, it’s just another challenge to be met by conservation or energy storage. In the meanwhile, he is working hard constructing a new building on his property. It’s the size of a small house and will be used as a commercial kitchen. The building is super-insulated, and it has a solar air heater and a solar water preheater. Nils is putting in LED lighting (more efficient than compact fluorescents). The heat is electric, but because of the clever designs my brother is using, very few kilowatt-hours are needed to keep the place warm. Nils plans to use what he’s learning as he builds the kitchen to retrofit two other buildings on his property to reduce their carbon footprints.

I’ve got to respect parts of my brother’s thinking. And I really applaud his building efforts. Not many of us put our money where we say our values are.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

By Dr. E. Kirsten Peters

When you fill your tank, you likely see a little sticker on the pump saying part of the fuel is ethanol. Ethanol is a biofuel, which means it comes from plants like corn, rather than from fossil fuel — ancient carbon that’s been buried within the Earth for millions of years.

Producing more biofuels is on the agendas of governments and private industry alike. Biofuels can potentially help nations become more energy independent. If a country can grow plants and produce biofuels from them, that nation could potentially import less crude oil. Biofuels, if done right, also could reduce the total amount of greenhouse gas emissions produced in the transportation sector.

But there are drawbacks, at least with corn-based ethanol. For one thing, using ethanol in our vehicles means we are essentially burning food as we tootle down the road. Food is pretty precious stuff in a hungry world, so a number of people are worried about corn-ethanol. It also takes considerable petroleum-based fuel to grow corn, harvest it, and process it into ethanol. So researchers around the world are on the lookout for better ways to make biofuels.

Biodiesel is another biofuel that you’ve likely heard something about. It’s blended into petroleum-based diesel to power trucks and diesel-fueled cars. Biodiesel is quite simple to make from vegetable oil. In freshman classes, I’ve led students to make it in small batches. But if biodiesel is made from oils we eat, it has some of the same drawbacks as corn-based ethanol.

Recently there was an interesting report about an advance made by scientists researching a new approach to making biodiesel. A team of researchers used genetically modified E. coli bacteria to convert sugar into a material very similar to petroleum-based diesel fuel. The fuel produced is so much like petroleum diesel, it can be used at full strength in engines.

Professor John Love, a synthetic biologist at the University of Exeter, was one of the scientists involved in the work. Talking with a reporter from BBC News, he said, “What we’ve done is produced fuels that are exactly the chain length required for the modern engine and exactly the composition that is required.”

Some people fear bioengineering when it comes to the food we eat, but there might be less resistance to the approach if it is used to produce fuel rather than vittles.

But there is more work to be done. E. coli doesn’t produce a lot of fuel. According to the BBC news report, it would take over 100 quarts of E. coli to produce a teaspoon of diesel fuel.

“Our challenge is to increase the yield before we can go into any form of industrial production,” Love said. “We’ve got a timeframe of about three to five years to do that and see if it is worth going ahead with it.”

The devil is in the details when it comes to biofuels developed so far. But don’t count researchers out – there are many good ideas being pursued all the world around.

 

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

By Dr. E. Kirsten Peters

I’m quite a dinosaur. I get some of my news the old fashioned way from hardcopy newspapers, and I still pay my bills with paper checks sent through the mail. But even I own a smart phone. The ability to keep up with work-related email, as well as messages from friends and family, is one fantastic benefit of the modern cell phone. I do, indeed, value the technological revolution through which we all are living.

Arron Carter and Mike Pumphrey are two research scientists at Washington State University who are doing work in dusty wheat fields that is being transformed by technology.

“It used to be that weighing the bag (of grain) was the only way we had to evaluate a variety of wheat,” Pumphrey said to me. “Yield is still the bottom line, but technology gives us tools for earlier identification of what will be fruitful lines of wheat.”

Some of the technology is pretty cool. The breeders now have tiny, unmanned helicopters they use to look at crops in the field. These remotely controlled copters are just a couple of feet in diameter. Special cameras on board record more than what the human eye can perceive.

“The cameras tell us information about photosynthesis and the water use of the plants,” Carter said. “They can even take the temperature of the plants.”

The devices can measure small changes.

“It’s best for us to work on sunny days with little wind,” Pumphrey said. “If a cloud comes over the sun, the plants change how they are photosynthesizing and that’s picked up by our sensors.”

In addition to sending aerial devices over fields of wheat, the pair of researchers uses a special GPS-guided tractor that has a variety of high-tech sensors on it.

“Instruments that are too bulky for the helicopters are on the tractor,” Pumphrey said.

Work like what Carter and Pumphrey do requires interaction with a variety of specialists. Engineers, for example, are an important resource for the wheat breeders.

“There’s a lot of diversity in our work,” Carter said. “We have to do a little bit of everything, from studying diseases in the wheat, to soil properties, to engineering. So, for example, we might pull in an engineer to help us develop a particular sensor, then apply that to what’s growing in the field.”

Pumphrey grew up in the number one wheat-producing county in Oklahoma. As a young kid, he didn’t even know you could grow anything but wheat. He later got into his line of work for pretty idealistic reasons.

“I had a love of plants, but I also wanted to do good. In this field, we work to produce more food using less resources and to help the farmers have lower environmental impact,” Pumphrey said. “We really affect many lives.”

If you like to eat bread and other foodstuffs made from wheat, you’ve got to wish modern wheat breeders well as they embrace technology to improve varieties of wheat on which farmers — and the rest of us — depend.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

High technology meets fields of wheat

By Dr. E. Kirsten Peters

As my friends and relatives know, I’m quite a dinosaur in several respects. I get a lot of my news the old fashioned way from hardcopy newspapers. I still pay my bills with paper checks sent through the mail. And nothing pleases me more when I get home at night than to find I have a “snail mail” letter from an old friend who took the time to put down ideas on paper with a pen.

But even I own a smart phone. The ability to keep up with work-related email, as well as messages from friends and family, is one fantastic benefit of the modern cell phone. I do, indeed, value the technological revolution through which we all are living.

Arron Carter and Mike Pumphrey are two research scientists at Washington State University who are doing work in dusty wheat fields that is being transformed by technology.

“It used to be that weighing the bag (of grain) was the only way we had to evaluate a variety of wheat,” Pumphrey said to me. “Yield is still the bottom line, but technology gives us tools for earlier identification of what will be fruitful lines of wheat.”

Some of that technology is pretty cool. Plant breeders now have tiny, unmanned helicopters they use to look at crops in the field. These drones are just a couple of feet in diameter and are operated by remote control. Special cameras on the helicopters record more than what the human eye can perceive.

Researchers can fly the helicopters 100 yards above a field to take a broad picture, or fly them 5 yards off the ground to measure properties in a test plot.

“The cameras tell us information about photosynthesis and the water use of the plants,” Carter said. “They can even take the temperature of the plants.”

These copters cost a few thousand dollars. The real money is in the cameras and sensors, which may cost up to $50,000.

Cameras on satellites high in the sky can also help characterize plants growing in a field. But it can be many days before a satellite makes a pass over a particular location. With smaller devices that the researchers can control, more measurements can be taken at the most opportune time.

“It’s best for us to work on sunny days with little wind,” Pumphrey said. “If a cloud comes over the sun, the plants change how they are photosynthesizing and that’s picked up by our sensors.”

In addition to sending small aerial devices over fields of wheat, the pair of researchers uses a special GPS-guided tractor that has a variety of high-tech sensors on it.

“Instruments that are too bulky for the helicopters are on the tractor,” Pumphrey said.

The instruments on the copter and the tractor are looking at what’s called “phenomics.” That’s a term that includes everything about the plant from growth rates to photosynthetic efficiency to the temperature in the canopy of the plants.

Work like what Carter and Pumphrey do requires interaction with a variety of specialists. Engineers, for instance, are an important resource for the wheat breeders.

“There’s a lot of diversity in our work,” Carter said. “We have to do a little bit of everything, from studying diseases in the wheat, to soil properties, to engineering. So, for example, we might pull in an engineer to help us develop a particular sensor, then apply that to what’s growing in the field.”

Pumphrey grew up in the number one wheat-producing county in Oklahoma. As a young kid, he didn’t even know you could grow anything but wheat. He later got into his line of work for pretty idealistic reasons.

“I had a love of plants, but I also wanted to do good. In this field we work to produce more food using less resources and to help the farmers have a lower environmental impact,” Pumphrey said. “We really affect many lives.”

If you like to eat bread and other foodstuffs made from wheat, you’ve got to wish modern wheat breeders well as they embrace technology to improve varieties of wheat on which farmers — and the rest of us — depend.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

By Dr. E. Kirsten Peters

Years ago I was a light smoker. Back in the day I thought nicotine did good things for my ability to think and learn. I was a serious student at the time, studying intensively seven days a week, so a powerful complement to black coffee was welcome in my life.

I both sympathize and empathize with smokers around me today. But I’m awfully glad I quit long ago, and I know many other former smokers who feel the same way. Quitting is worth all the short-term distress it can entail.

Some recent scientific news got me thinking again about smoking and how it affects both smokers and those around them. In short, there’s plenty of evidence that passive or second-hand smoke is detrimental to people living with smokers. That means that quitting helps not just smokers, but those who share homes (and cars) with them.

Recently the European Heart Journal published a study about the effects of parental smoking on kids. The research focused on some 2400 children in a cohort in Finland and over 1300 in a group in Australia. Researchers noted the smoking behavior of parents — whether the adults were non-smokers, or if one or both of them smoked. When the kids grew up, the researchers examined the kids’ arteries via ultrasound exams.

The study found that artery walls were thicker in kids who had grown up in homes where both parents smoked. Thicker arteries are bad news, making for greater risk of strokes or heart attacks. On average, the kids who grew up in homes where both parents smoked had arteries that were 3.3 years “older” than those who grew up in smoke-free homes. These changes were permanent — a sobering fact to contemplate for any parent (and I might add, any grandparent around the grandkids).

Dr. Seana Gall, lead author of the study, told ScienceDaily, “Parents…should quit smoking. This will not only restore their own health but also protect the health of their children into the future.”

There was further bad news for kids who had two parents who smoked.

“Those with both parents smoking were more likely, as adults, to be smokers or overweight than those whose parents didn’t smoke,” Gall said.

Once again, the news from the world of medical research suggests it’s time for people to quit smoking. If you smoke and you have kids (or grandkids) to consider, please talk with your health care provider about an approach to help you kick the habit. Even if you’ve tried in the past to quit but have failed, this next effort could set you free. It took me more than one attempt to quit, but it was one of the best things I did back in the day.

I know first-hand it ain’t easy to stop smoking. But the life you save might be your own — and you could also be helping the next generation avoid permanent and harmful changes to their young bodies.

I’m pulling for both you and your family.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

By Dr. E. Kirsten Peters

I once experienced a small earthquake when I was visiting the Sam Francisco Bay Area in California. The natives thought little of the temblor but I was impressed that the ground beneath my feet could suddenly and without warning start to shake.

Later, when I majored in geology in college, I learned that my native Northwest is also at risk for earthquakes, as is much of Alaska. Another part of the country with a history of large quakes is called the New Madrid Seismic Zone. It’s a pretty large region centered near where the states of Arkansas, Missouri, Illinois, Tennessee and Kentucky come together in the lower Midwest.

Some earthquake-rich areas are easier for geologists to understand than are others. In the Pacific Northwest, for example, major tectonic plates are coming together. Their movement guarantees earthquakes from time to time. In California, quite famously, the San Andreas fault marks the place where two plates are moving past each other. This leads to shallow earthquakes that can be particularly destructive. But there are also regions of the country — like the New Madrid area — where major quakes can occur away from plate boundaries .

To understand the New Madrid Seismic Zone in the middle of the continent, we first need to review a bit of history. Mother Nature was heard from in a big way in late 1811 and early 1812 in that region. According to a U.S. Geological Survey website, during that time the area experienced three very large quakes with magnitudes over 7.

The way that geologists now think of the quakes is basically this: the first mega-quake occurred on December 16 of 1811. The second quake occurred about a month later, on January 23, 1812, and the third two weeks after that, on February 7, 1812. But those quakes were not isolated. There were numerous other quakes that geologists now interpret as likely aftershocks. The aftershocks may have been as big as magnitude 6 or 6.5. That means the “aftershocks” would count as large quakes in their own right by human standards. Numerous smaller aftershocks also shook the region.

There are written accounts from people living in the lower Midwest at the time of the big quakes that describe ground movement that went on and on. Structures in St. Louis were damaged. In short, it was not a good place to be when the Earth decided to release enormous amounts of energy that were pent up within it.

From that time down to the present there have been small temblors in the New Madrid Seismic Zone. One question that has arisen for geologists is whether to think of these quakes as long-term aftershocks of the major events of 1811-1812, or to think of them as something else. It’s an important question because if the quakes have been aftershocks, there might be little stress building within the Earth in the area. That would be good news for everyone living in the lower Midwest.

Recently two researchers published a piece in Science about their efforts to understand the long history of quakes in the region. Morgan Page and Susan Hough of the U.S. Geological Survey used computer modeling of aftershocks to analyze what’s been happening in the New Madrid area. They found that there haven’t been many quakes of “moderate” size – that is, in the approximately magnitude 6 range — but there have been a lot of small quakes in the region.

This pattern, the scientists argue, isn’t consistent with the idea that all the quakes are aftershocks of the events of 1811 and 1812. Instead, the recent history of quakes in the area suggest that ongoing Earth processes continue to generate stress in the region. And that means some energy will likely need to be released — perhaps in another quake on the scale of those that hit in the early 1800s.

Geologists are so far unable to make specific predictions of when quakes will occur. But it seems likely, if Page and Hough are right, that one day the lower Midwest will have to cope with a major quake. It’s not good news, but it’s a risk we need to face squarely — and it highlights the importance of preparedness for individuals, families and municipalities.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.

By Dr. E. Kirsten Peters

My household accumulates quite a number of plastic shopping bags. Most come home with me from the grocery store. I use them to line the little garbage pail that sits under the kitchen sink and the wastebasket that’s in the bathroom. I also have the joy of using them to pick up poop deposited by Buster Brown, my faithful mutt from the pound.

But if you don’t have uses for the plastic shopping bags you bring home, what do you do with them? Researchers hope that one day — perhaps sooner rather than later — your bags may be turned into alternative fuels such as diesel. That’s right, plastic shopping bags could help power diesel engine cars and pickup trucks.

It’s not as pie in the sky as it may sound. Converting shopping bags into fuel requires less energy than it produces. The key is the high-temperature breakdown of plastic in the bags — done in the absence of oxygen, or anaerobically.

The lead author of a recent study on this topic is Dr. Brajendra Sharma of the Illinois Sustainable Technology Center. The ISTC is part of the University of Illinois. His research write-up was recently published in the journal Fuel Processing Technology. Sharma’s article points out that about a trillion plastic bags were produced in the U.S. in 2009, the last year for which figures are available. Of these, only about 13 percent were recycled. Some of the rest were doubtless reused for household purposes, like mine are, and after that headed to landfills. But many of the bags aren’t recycled or reused and go either directly to landfills or are released into the environment as litter.

Plastic bags that become litter blow around and cause a number of problems beyond being an eyesore. They can kill animals that ingest them or become tangled with them. In the oceans, they compose part of what’s termed the Great Pacific Garbage Patch of floating trash.

“Over time, this material floating in the oceans breaks into tiny pieces. It’s ingested along with plankton by aquatic animals,” Sharma emailed me.

The material in plastic shopping bags has been detected in the oceans near both the north and south poles. It’s also a problem in the Great Lakes. Because the plastic apparently takes centuries to fully degrade in nature, the issues that the bags pose are long term.

But Sharma and his colleagues have an alternative use for the bags. Once the plastic is broken down anaerobically in a lab, it yields a variety of useful chemicals including solvents, engine oils, gasoline and natural gas. The bulk of the material produced is an alternative diesel fuel — one that Sharma and his co-workers found to be a good blending component for regular diesel.

“This approach can also be applied to other low value plastics as well,” Sharma wrote to me.

I’ve often thought that there’s no single solution for pollution problems. And while turning plastic bags into diesel may only work for some bags, it’s an interesting approach to getting rid of what otherwise would be trash — while producing a valuable commodity.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.