UT Hosts International Symposium To Explore Biotechnology's Future

by David Brill

From its modest beginning in rendering manure into inoffensive--though nutrient-rich--potting soil, biotechnology, the controlled use of beneficial microorganisms, has been applied in many ways to neutralize noxious substances and heal damaged ecosystems.

Its been used, for instance, to sop up remnants of the Exxon Valdez oil spill in 1989, remediate jet fuel and other petroleum products in soils surrounding underground storage tanks, and destroy PCBs lurking beneath utility transformers.

The future will likely see biotechnology make its way farther up the waste stream into the realms of pollution prevention and waste minimization, and as it does, biotechnology will play a key role in shaping a sustainable future.

Biotechnologys present and future potential formed the theme of an international symposium held this past April in Knoxville at The University of Tennessee (UT).

Hosted by UTs Waste Management Research and Education Institute (WMREI) and the Center for Environmental Biotechnology (CEB), "Biotechnology in the Sustainable Environment" drew more than 100 participants from 22 states and provinces and nine countries.

This issue of InSites is devoted to the symposium and features several stories highlighting specific symposium presentations. Our coverage begins on page two.

Over the course of three days, symposium panelists explored key areas of biotechnology, including bioremediation, waste treatment, risk and policy issues, pollution prevention, and techniques for evaluating and monitoring the action of beneficial microbes.

"This symposium did an excellent job of giving participants a vision of the breadth of biotechnology and the drivers that will shape its future," says Gary Sayler, who serves as director of both WMREI and CEB. "It also provided a broad international perspective on both the use of biotechnology and the widely varying regulatory frameworks that afect its development and application."

Presenters from eight nations outside the United States, including Switzerland, Mexico, Canada, Japan, Russia, Taiwan, Belgium, and the Netherlands, explored biotechnology issues specific to their countries environmental challenges.

Panelists from the United States, Mexico, and Canada alluded to opportunities for North American collaboration based on their nations relative strengths.

For instance, U.S. remediation experts have gained valuable experience in using biotechnology to clean up the legacy of industry and weapons development.

Canada boasts a federal government com mitted to supporting biotechnology research and development. In fact, since 1983, the Canadian government has spent $1 billion on its National Biotechnology Strategy, which seeks to apply biotechnology to environmental problems in its agricultural, forestry, and mining sectors.

Meanwhile, Mexico, whose environmental standards lag behind those of its northern neighbors, presents a receptive market for development and application of biotechnological solutions.

This years symposium built on a foundation established by a 1990 conference, also hosted by UT, titled "Environmental Biotechnology: Moving From the Flask to the Field."

"With the 1990 conference, we were trying to emphasize the tremendous amount of untapped fundamental biotechnology that could be brought forward for hazardous-waste remediation and control of pollution," says Sayler.

"Six years later, we can point to many of those technologies that have been developed in a research context and applied in the field. Natural bioremediation and attenuation have come a long way toward becoming accepted treatment technologies."

The conference received funding from a number of private corporations and government facilities, including Dow, DuPont, Eastman, General Electric, International Technology Corporation, Oak Ridge National Laboratory, Science Applications International Corporation, and Procter&Gamble.

Biotreatment News and The Bio Cleanup Report, national newsletters covering the technology and business of biotreatment, helped promote the event.

According to Sayler, conference proceedings will be published by the end of the year.r

For more information, contact Kim Davis, The University of Tennessee, WMREI, 311 Conference Building, Knoxville, TN 37996-4134, or call 865-974-4251.

Flower Power

by David Brill

Ask most people to conjure up the image of a toxic-waste site, and they might call to mind a barren expanse of land defined by a chain-link fence.

Put the same request to biotechnologist Burt Ensley, and he'll likely envision a sprawling field of bright yellow flowers.

Ensley is president and CEO of Phytotech, a New Jersey-based environmental biotechnology firm, and his vision, though romantic, is no wistful daydream.

Besides imparting a touch of beauty to an otherwise nondescript plot of earth, Ensley's flowers are drawing arsenic, cadmium, lead, strontium, or a whole host of other contaminants from the soil and water swaddling their roots.

These and other inorganic metals are to plants what vitamin supplements are to humans: Plants draw them from the soil, water, and even air and use them as nutrients for growth. In the process, the innocent-looking mustard plants, sunflowers, hyacinths, pennyworts, and duckweeds that blossom in Ensley's test fields are concentrating these hazardous metals in their shoots, stems, roots, and leaves. As they do, they're advancing a field of biotechnology known as phytoremediation or rhizo- filtration.

Under the watchful eye of specialists like Ensley, these plants are being selectively bred for their contaminant-absorbing capabilities, and Ensley believes it's only a matter of time before phytoremediation begins to be used on a large scale.

"The remediation site of the fuhotograph of a meadow speckled with colorful blossoms.

As proof, Ensley points to a second photo. This one depicts sunflowers, drifting in a tranquil pond, their roots dangling from Styrofoam floatation jackets that buoy them to the surface. Looming in the background is the damaged reactor unit at Chernobyl. The pond contains a radioactive soup consisting of cesium and strontium.

Despite the area's reputation as the "most radioactive spot on Earth," the sunflowers seem happy enough, stretching to a height of 6 feet.

Ever versatile, plants have proven as adept at drawing lead from contaminated soils as they are at sipping cesium from a radioactive pond. Ensley displays yet another photograph, this one of an 1850s-vintage house in New Brunswick, New Jersey.

In the photo, several rows of Indian mustard plants sprout from the ground along the house's drip line. The toxic residue from countless coats of lead-based paint have been deposited there by rain. As the plants grow, they extract lead to a depth of about 30 centimeters (11.7 inches).

So far so good, but what becomes of these plants after they've eaten their fill? Don't they, with their cells swollen with contaminants, represent a hazard?

The answer is yes, but one that's much easier to contend with than a field of toxic soil.

"If you start with 10,000 tons of contaminated soil, and wind up with 10,000 tons of contaminated plants, you really haven't solved the problem," says Ensley.

"The fact is," he continues, "the plants achieve concentrations of these metals that are dramatically higher than concentrations in soils."

For instance, before the Chernobyl sunflowers are harvested, dried, and incinerated or landfilled, their roots may contain concentrations of cesium that are 8,000 times higher than concentrations in the surrounding water.

Because the contaminants are concentrated in the plants' tissues, waste managers face a greatly reduced burden in disposing of the harvested plants compared to the challenge of treating soil or water using conventional means.

Beyond ease of disposal, these plants pose a host of other benefits.

First, these plants grow rapidly. In fact, it's not unusual for biotechnologists to grow as many as three crops in one summer.

Second, the approach requires little maintenance beyond preparing the soil, planting the seed or shoots, and harvesting and disposing of the mature plants.

And third, says Ensley, phytoremediation is cost-effective. Consider, for instance, that conventional treatment measures--including excavation of contaminated soil and transport to a toxic landfill--can exceed $600,000 for one hectare (2.47 acres). The ticket for phytoremediation falls somewhere between $80,000 and $260,000 to remediate the same plot of land.

"With phytoremediation," says Ensley, "it suddenly becomes economically feasible to remediate sites that might otherwise have remained untreated and therefore unpro- ductive."

For more information, contact Burt Ensley, Phytotech, Inc., 1 Deer Park Drive, Suite1, Monmouth Junction, NJ 08852, or call 908-438-0900.

Biotechnology with a Blast

by Lori Phan

You won't find trinitrotoluene (TNT) listed as an ingredient on the side of a cereal box or on the shelves of your local grocery store.

Nevertheless, it's a main menu offering at Joliet Army Ammunition Plant in Joliet, Illinois, where microorganisms are having, well, a virtual blast for breakfast.

Currently, there are 26 active or inactive U.S. Army sites on the National Priorities List (NPL) that once produced or processed ammunition. The NPL is a roster of the nation's most hazardous contaminated sites.

These 26 sites are contaminated with TNT, which was produced beginning at the turn of the century for use in munitions.

John Manning and fellow researchers at Argonne National Laboratory n Argonne, Illinois, have been looking for a way to clean up this contamination using the microorganisms naturally living in the soil.

In the past, TNT-contaminated soil was incinerated, which proved to be expensive, costing $600 per cubic yard of contaminated soil. At that rate, using incineration to remediate all 26 sites could cost taxpayers in excess of $1.5 billion.

Intent on cutting cleanup costs, Argonne scientists are trying to find techniques for enhancing microbes' natural ability to destroy TNT.

In the search for microbial appetite stimulants, researchers at Argonne spent 18 months excavating 4,000 pounds of TNT-contaminated soil (easily identified by its signature red tint) from the Joliet Army Ammunition Plant.

They then placed the dirt into a slurry reactor--a large, metal holding tank with a rotating arm for mixing or stirring the soil. Here, billions of microorganisms set to work on the contaminants.

Although microorganisms can destroy TNT, the compound doesn't supply sufficient nutrients to sustain the organisms' growth and survival. To resolve the dilemma, scientists sought a magic additive that would increase the organisms' ability to degrade TNT.

After testing many salt- and sugar-based compounds, researchers discovered that their microorganisms have a savor for sweets.

Ultimately, they found that adding molasses to the soil in the slurry reactor turns the microbes into ravenous feeders.

Researchers also found that as temperatures climb, the microbes become more active. In fact, scientists discovered that the ideal temperature for bioremediation falls between 22-24 degrees Celsius (71.6-75.2 degrees Fahrenheit).

Equipped with this knowledge from the laboratory, biotech- nologists intend to continue to research this remediation technology, which, says Manning, is as much as 30 percent cheaper than incin- eration.r

For more information, contact John Manning, Argonne National Laboratory, Environmental Research Division, Building 203, 9700 South Cass Avenue, Argonne, IL 60439-4843, or call 708-252-7854.

Peering Down the Drain

by David Brill

While some companies might care little for what becomes of their goods after they leave store shelves, industry giant Procter&Gamble (P&G) is intent on following its cleaning products--including its laundry detergents--right down the drain.

Laundry detergents--like most cleaning products--are used once then rinsed away. After leaving the washing machine, they travel down the drain and into the sewage system, where they may linger for several hours or even days before reaching the sewage treatment plant.

There, they are besieged by microbes and ultimately wind up as part of sludge or remain in the water. The treated water is discharged into rivers after about eight hours, where it mixes with natural waters and the outflows from other sewage treatment plants on their way to the ocean.

Sludge from these treatment plants, which may reside at the plants for as long as two weeks, often winds up being spread on farm fields in the form of fertilizers.

"If components of the detergent were not biodegraded or otherwise removed," says Tom Federle, a principal research scientist with P&G's environmental microbiology division, "they could become widely dispersed in the environment and contribute to soil and water pollution."

According to Federle, knowing what becomes of these chemicals once they enter the environment is critical to advancing the goals of pollution prevention.

In particular, manufacturers are concerned about how quickly and thoroughly and under what conditions the biodegradation process will render their products' ingredients harmless.

That's where "fate assessment" comes in. In the past, researchers relied on rudimentary experiments that involved introducing excessive doses of the chemicals into test vessels and returning weeks or months later to assess the results.

Often these experiments were fraught with inaccuracies, mainly because they failed to replicate or predict the actual conditions present in the environments into which these compounds are discharged.

"Researchers could hope only to establish that a compound was biodegradable without knowing under what conditions or at what rate," says Federle.

During the early 1990s, P&G scientists began using a new fate-assessment method that's as quick as it is accurate. It works like this:

or research purposes, compounds in P&G products--in this case, laundry detergents--are tagged with a carbon-14 isotope. The isotope is incorporated into a compound's molecule and serves as a radioactive marker that allows scientists to closely monitor a compound's fate.

The test environments into which these compounds are introduced reflect the actual conditions in sewage systems, waste treatment plants, and rivers. In fact, waste water or sludge from sewage treatment plants is often used in the laboratory.

This method allows biotech- nologists, using sophisticated analytical equipment that "reads" the radiolabeled chemical, to predict how much of a product will biodegrade at various stages in its journey from consumers' homes to the sea or farm field.

"With this testing method," says Federle, "we can tell how much of the product is being converted to carbon dioxide, how much is being digested by microbes, and how much is being converted to metabolites."

To assess the method's accuracy, P&G researchers estimate the level of the chemical they expect to find in a sewage treatment plant's outflow and then compare it to a sample from the plant's outflow.

As often as not, says Federle, P&G scientists find that their estimates fall within micrograms of the actual environmental conditions.r

For more information, contact Tom Federle, The Procter&Gamble Company, Ivorydale Technical Center, Cincinnati, OH 45217-1087, or call 513-627-7296.

Kicking the Chemical Habit

by Lori Phan

Despite its contribution to the quality of life and general prosperity of the developed world, the industrial revolution has left behind a legacy of air, water, and soil pollution. Much of it has resulted from the harsh chemicals used in various manufacturing processes.

In response, public, regulatory, and industrial sectors are beginning to demand that industries take a greener approach to their products and manufacturing processes, according to Glenn Nedwin of California-based Novo Nordisk Biotech Inc. The company, a research-and-development subsidiary of a Denmark-based enterprise, specializes in developing new applications for existing as well as engineered enzymes in various manufacturing processes.

One way for manufacturers to "go green" is to replace the environmentally damaging chemicals they use--among them phosphates, carbonates, surfactants, silicates, and chlorine bleach--with harmless, hard-working enzymes.

Enzymes are proteins produced by bacteria and fungi that work to degrade other proteins and compounds without posing risk to the environment.

Take, for example, laundry detergents--the single largest product segment using enzymes today. In detergents, enzymes help remove stains by breaking down the starch that acts as a glue, binding the stain to fabrics.

Enzyme-based detergents work in mild water temperatures, conserving energy and natural resources.

For instance, most chemical-based detergents work best in water that's been heated to 140 degrees Fahrenheit. It takes about 37,000 tons of coal to fill the washing machines of about 5 million people with water that hot.

By contrast, an enzyme-based detergent functions better at only 104 degrees Fahrenheit, which consumes only 224 tons of coal for the same quantity of water.

According to Nedwin, using enzymes poses other environmental benefits: Enzymes are totally biodegradable, they leave no harmful residues, and they pose no threat to aquatic life or sewage-treatment processes.

Enzymes have also found their way into the fashion industry where they're allowing blue-jean manufacturers to "age" denim products through a process dubbed "bio- stoning."

Traditionally, jeans were literally beaten with pumice stones during the washing process to achieve that ever-popular "worn-in" look.

However, manufacturers are discovering that using enzymes to fade jeans is much more efficient and environmentally benign. For instance, 1 cup of enzymes can replace about 100 times its weight in pumice stones. Use of enzymes also makes disposing of the stones unnecessary and eliminates the abrasive pumice dust that might damage machines and other equipment.

According to Nedwin, enzymes are also being used to process leather, paper, and particle board and to de-ink recycled paper.

Although enzymes are widely used, they currently make up only a small percentage of the overall industrial chemical market.

Manufacturers sometimes discover that the newer enzyme technologies are incompatible with their older, chemical-based technologies.

Despite the initial high cost of revamping outdated chemical-based machines and processes, however, Nedwin insists that industrial use of enzymes is on the rise as many chemically dependent industries discover the advantages of breaking harmful chemical habits.r

For more information, contact Glenn Nedwin, Novo Nordisk Biotech, Inc., 1445 Drew Avenue, Davis, CA 95616-4880, or call 916-757-8100.

Turning Brownfields Green

by David Brill

We've all seen them. Vacant lots in inner-city neighborhoods once occupied by gas stations, auto garages, or small factories. Collectively, they're known as "brown-fields."

The enterprises have gone out of business or moved on, leaving behind soil and groundwater that may be laced with hazardous wastes, including gasoline, oil, solvents, heavy metals, and PCBs.

Contaminated brownfields are often posted and encircled by fences and left to languish. As they do, they drive down property values and communicate a message of urban blight and economic decline to all who pass by.

Prospective buyers are leery of purchasing these polluted lands, fearing that the cost of remediation may far exceed the lands' productive value.

American cities contain more than 450,000 such sites. And while most people regard them as the mark of a city's fading fortune, Maureen Leavitt, a bioremediation specialist with Oak Ridge-based Science Applications International Corporation, sees them as a symbol of opportunity.

In particular, Leavitt sees brownfields as perfect locations for use of "passive," or "intrinsic," bioremediation, which could return many of these vacant lands to use.

This cleanup technology allows the contaminant-destroying organisms naturally present in soil to destroy certain toxic substances without the need to excavate the soil or introduce amendments to enhance the remediation process. The technique is also known as "natural attenuation."

The benefits of intrinsic bioremediation are many. It costs much less than more aggressive treatment methods. And, because it works more slowly, it spreads costs out over a number of years.

For instance, says Leavitt, intrinsic bioremediation of an urban brownfield might cost $70,000 over the course of 10 years. By contrast, an aggressive pump-and-treat approach--which would extract and decontaminate polluted groundwater before returning it to the environment--might cost as much as $600,000 over five years.

And while the microbes work silently in the soil, the surface remains undisturbed, allowing developers to put less-toxic vacant lots to use quickly.

Though intrinsic bioremediation isn't well suited to all brownfields, Leavitt maintains that it's a perfect match for those exhibiting a few shared characteristics.

First, these sites must pose only minimal risks to people and animals living nearby. Any site that threatens human health is a candidate for more aggressive treatment methods.

Second, these sites must not be subjected to new contaminant releases. In other words, intrinsic bioremediation would not be an option for a site on which an enterprise continued to create pollution.

Third, candidate sites should boast barriers that would prevent pollutants from migrating off-site through movement of water or air. These barriers can include caps made of soil, asphalt, or clay and erosion-controlling measures such as ground cover.

Before waste managers select intrinsic bioremediation, says Leavitt, they need to assess the area's suitability.

Such assessment involves understanding the site's characteristic flow of water, evaluating the soil for the presence of beneficial microbes, and crafting a model to demonstrate how and within what time frame the natural attenuation process should achieve its goals.

"Beyond those concerns, waste managers should look at potential end uses for the site, which will help them decide how 'clean' the site needs to be," says Leavitt, "and they should set up a monitoring system to confirm that the natural attenuation process is working."

Though the technology that Leavitt endorses is somewhat passive, Leavitt, as a biotechnology advocate, is anything but, especially when it comes to touting bioremediation as a solution to the brownfield dilemma.

In fact, in Leavitt's estimation, brownfields will represent a major milestone in the use of bio- remediation. One of the first milestones involved the Exxon Valdez oil spill, which dumped 240,000 barrels of crude oil into Alaska's Prince William Sound in 1989.r

For more information, contact Maureen Leavitt, SAIC, 800 Oak Ridge Turnpike, Oak Ridge, TN 37831, or call 423-481-4614.

Costs, Risks Must Define Clean

by Lori Phan

For many of us, when it comes time to clean the house, we don't quite know where to start.

By contrast, Don Ritter, chairman of the National Environmental Policy Institute (NEPI) and former U.S. Congressman, claims that when it comes to cleaning up the environment, our problem is that we don't know where to stop.

Ritter's perspective has emerged from having watched Congress battle over such environmental cleanup issues as the reauthorization of Superfund, the Clean Air Act, and the Resource Conservation and Recovery Act.

Often the concerns at the heart of the feud are these: When it comes to remediating toxic sites, how clean do these sites really need to be? What programs will suffer if we reallocate money away from other projects to fund environmental cleanup? And how much will our remediation efforts actually reduce risk and protect health?

Ritter contends that these questions will help legislators establish environmentally acceptable endpoints (EAE) for cleanup tasks. Often, these endpoints will fall short of returning toxic-waste sites to pristine conditions, but they may reflect conditions clean enough to support certain restricted uses.

"The United States is at a crossroads," says Ritter. "To ensure cleaner, yet more cost-managed environmental programs, we must determine how much we can afford to spend on cleanup and how much cleanup that money will buy."

An EAE, says Ritter, is the point at which you say, "this site is as clean as it needs to be for a specific use." Often, this level of clean represents the lowest acceptable level of "cleanliness" in terms of posing no threats to humans and the environment.

According to Ritter, an EAE is determined by weighing the risks, benefits, and costs of site remediation. Take, for example, the federal government's decision to clean up numerous radiation-contaminated sites around the country.

The government first has to assess the actual risk each site poses if it is left alone, partially remediated, or completely restored. To arrive at the answer, the government must assess how the land is currently being used and how it might be used in the future. Based on these uses, what risks are faced by the people who live, work, and play nearby?

Next the government would examine its cleanup options in terms of the effectiveness and cost of each.

In a perfect world, says Ritter, we'd excavate and treat every granule of contaminated soil.

"The problem is that these costs can be excessive, and we can't afford to do that," he says. "Spending public funds isn't practical when leaving trace amounts of contamination in the soil causes no real dangers."

Biotechnology poses a practical treatment option, particularly for sites that are hazardous enough to require cleanup but which don't need to be cleaned up immediately.

Though less expedient and thorough than incineration, biotechnology can affordably render sites clean enough for multiple uses.

Ritter stresses that the "how-clean-is-clean?" question grows in importance today as federal and state budgets become ever more constricted.

"Spending money here means cutting money there," he says. "If we hope to sustain important public programs while attending to environmental threats, we need to determine a level of cleanliness that is both acceptable and affordable." r

For more information, contact Don Ritter, National Environmental Policy Institute, 1101 16th Street NW, Suite 502, Washington, DC 20036, or call 202-857-4784.