InSites is a quarterly newsletter that highlights the personalities and projects of the Waste Management Research and Education Institute (WMREI) of The University of Tennessee. WMREI is an affiliate of the EERC.
WMREI was created in 1985 as a state-funded Center of Excellence. Research areas include solid-, hazardous-, and nuclear-waste management; waste minimization; and pollution prevention.
Biotechnology is the focal point of the institute's technical research, while issues involving public attitudes and federal/state policies related to waste-management issues are the primary concerns of the institute's policy research.
For additional information about InSites, or to be added to our mailing list, please write InSites, WMREI, The University of Tennessee, 311 Conference Building, Knoxville, TN 37996-4134, call 865-974-1156, or fax 865-974-1838. Or, if you prefer, email us.
Table of Contents
Taking on Foodborne
Toxins , On
the Waterfront Ramping
Down,
Elise LeQuire
Staff Citings 
Have you ever felt sick a few hours after eating a tuna steak or a grilled filet of mahimahi? Unfortunately, you’re not alone, and medical experts predict that the number of seafood-borne food poisoning cases could be on the rise as health-conscious consumers increasingly substitute fish for beef.
Because spoiled fish doesn’t always look or smell different from fresh fish, however, it’s hard to tell when it’s time to pull it from an ice-packed display window or refrigerator and throw it out. Testing techniques do exist for monitoring seafood spoilage, but they’re either too expensive or too complex for routine use, says Steven Ripp, a research assistant professor with the University of Tennessee’s (UT) Center for Environmental Biotechnology (CEB). What the food industry urgently needs is a low-cost, rapid technique for monitoring food quality, and that’s where CEB researchers are hoping to make a difference.
Using CEB’s patented biosensor technology, Ripp and his colleagues are working to develop a new detector for histamine, the primary culprit behind seafood-borne disease outbreaks. The biosensors are made up of a tiny computer chip layered with living, bioluminescent microorganisms that are genetically engineered to emit light when they come into contact with the targeted substance. These detectors were initially developed for monitoring a wide range of environmental contaminants. Now, in the foodquality arena, the researchers’ goal is to develop a model sensor for toxins in food commodities.
“If we can successfully demonstrate this application, it could lead to a very wide range of new sensor technologies that could be used to evaluate both the quality and safety of many types of food products,” says CEB Director Gary Sayler.
FROM SEA TO TABLE
The researchers’ first target is histamine, a naturally occurring substance
implicated in nearly half of all reported seafoodrelated illnesses in the United
States, according to statistics from the Centers for Disease Control and Prevention.
Overall, seafood ranks as the third most prevalent cause of U.S. food-borne
disease outbreaks (see graph).
Histamine is a toxin produced by bacteria that are generally present in fish muscle. “As long as the fish are swimming around in cold water, these bacteria don’t grow very well,” Ripp notes. Once the fish are caught, however, and left for any length of time at room temperature, these bacteria can quickly produce a lot of histamine. Making matters worse, once the histamine toxin is formed, no amount of heating, freezing, canning, or smoking can eliminate it.
When people ingest fish with high enough concentrations of histamine – current Food and Drug Administration (FDA) guidelines specify 50 milligrams of histamine per 100 grams fish as being toxic—they can experience a variety of symptoms ranging from nausea, diarrhea, and vomiting to neurological problems such as a tingly feeling in the fingers, says Michael Davidson, a professor in UT’s Department of Food Science and Technology. Although symptoms are usually mild, persisting from several hours to a few days, serious cardiac and respiratory problems can occur as well.
“One of the problems we have is that we don’t really know when these organisms grow to sufficient levels in some of these fish or fish products to tell when there’s enough histamine there to make somebody sick,” Davidson says. “If we had a better way to tell this, we might be able to prevent some of these food-poisoning outbreaks.” The key to curbing and even preventing histamine formation in the first place, according to both Davidson and Ripp, is rapid cooling of fish after catching and maintenance of adequate refrigeration during handling and storage. But there are numerous points along the way where mishandling can occur, starting aboard the fishing vessel, at the processing plant, in the distribution system, and in the hands of end users, be they restaurant owners, grocery store managers, or consumers.
DETECTION TECHNIQUES
Currently, the FDA requires testing for histamine only upon receipt of the fish
by the primary processor, and only in tunas and mahimahi, which are some of
the fish most prone to histamine formation. Other fish types often implicated
in histamine poisoning, however, include mackerel, bonito, blue- fish, salmon,
amberjack, herrings, sardines, and anchovies. With these fish and at all other
levels of handling, signs of spoilage are detected only through visual and sensory
examination, Ripp notes, both of which are known to be poor indicators of fish
quality.
Where testing is conducted, chromatographic techniques are by far the best and most sensitive. “But due to the extensive cost, time, and complexity involved, using them on a routine basis is difficult, if not impossible,” Ripp says. Other more rapid testing kits are commercially available, but at more than $10 a test, they remain too expensive for routine quality-assurance testing.
As an alternative, Ripp and his colleagues are genetically engineering a microbe, known by the scientific name Arthrobacter globiformis, to sense histamine in rapid, simple, and inexpensive assays. And, based on the other biosensors developed at CEB, this one will translate into a sensor roughly 5 mm2 in size capable of detecting histamine within an hour in the low part-per-billion levels for a cost of about $2 per unit, Ripp says.
Another advantage to the biosensor technology is that it’s a totally autonomous system. “You don’t have to add anything to the test tube to get a response; you just throw in the bacterial cell, and if it detects histamine, it glows,” Ripp says. “In every other system out there, you have to add some substrate to make the system work,” and use specialized machines to read the results, which adds to the cost. With the CEB technology, the light intensity emitted correlates to the concentration of the contaminant and can be read by simple, inexpensive, hand-held photoluminometers.
Ripp and his colleagues envision the sensor’s use in three different types of applications—in the high-throughput monitoring required in food-processing facilities, in the field where a dock inspector needs to know whether to accept or reject a large shipment of fish, and at grocery and restaurant outlets where managers could monitor for freshness.
With the genetics of the organism almost complete, CEB researchers plan to begin testing the sensor early in 2004. If it works, “there are a number of bacterial toxins for which this would be useful,” Davidson says. Some of the toxins that pose the greatest concern to the food industry include mycotoxins, or molds that can contaminate grains or nuts; Staphylococcus enterotoxins, which are often found in meat and dairy products; and Botulinum toxins, which are often found in canned foods.
The technology “could also have important implications for bioterrorism issues with respect to food safety,” Sayler says.
“While histamine is indicative of the natural spoilage process, the model system that’s being developed can be readily transmitted to other systems where you might be looking for an induced toxin that was put into a food product deliberately,” such as the deadly poison riacin.
*
* *
For more information contact Steven Ripp,
CEB, The University of Tennessee, 676 Dabney Hall, Knoxville, TN 37996-1605,
call 865-974-9605, or e-mail saripp@utk.edu.
A collaborative effort relies on education to help curb nonpoint source pollution and improve water quality in Tennessee.
By Constance Griffith and David Brill
BETWEEN 1990 AND 2000, TENNESSEE ranked as the nation’s 14th fastest growing state, according to U.S. Bureau of the Census, with a population increase of nearly 17 percent.
Such rapid growth bodes well for developers and others in the construction trade, but all too often, rapid growth is accompanied by declining environmental conditions, particularly water quality.
Impaired water quality can result from construction-site sediment and debris entering rivers and lakes and increases in pavement and other impervious surfaces, which can contribute to runoff—or nonpoint source—pollution. (For more information on nonpoint source water pollution, see “Nonpoint Source Pollution and Water Woes” below.)
But is it a given that growing communities will experience declines in water quality?
Not at all, says Tim Gangaware, associate director of the University of Tennessee’s (UT) Water Resources Research Center (WRRC). WRRC is a subunit of UT’s Energy, Environment and Resources Center.
“Community planners and engineers can—and should—be trained to consider the impacts land use will have on water quality,” he says. “They can review site designs and plan for water quality just as they do for public safety, schools, or traffic. They can encourage developers to adopt best management practices for protecting the quality of the water in their areas.”
To that end, Gangaware and WRRC Senior Research Associate Ruth Anne Hanahan have partnered with the Tennessee Valley Authority (TVA), the Tennessee Department of Agriculture’s Nonpoint Source Program, the U.S. Environmental Protection Agency, the Southeast Watershed Forum, the communities of Alcoa and Maryville, and Blount and Knox counties to develop and pilot the Tennessee Growth Readiness (TGR) leadership training program.
TGR training aims to build awareness about water-quality issues linked to land use across Tennessee and puts a variety of resources in the hands of administrators to help them address water pollution in their communities. Much of the information provided by the program responds to new Clean Water Act requirements.
For instance, currently more than 80 Tennessee communities must meet the National Pollution Discharge Elimination System’s Stormwater Phase II MS4 [municipal separate storm sewer systems] requirements.
Roughly speaking, Phase II MS4s include smaller MS4s in urbanized areas, those not included in Phase I (Phase I MS4s serve populations of 100,000 or more). To qualify for a permit to operate stormwater discharge systems, communities must adopt a six-point stormwater management program.
Once this management approach is implemented, entire communities—from homeowners to home builders—become part of the plan to reduce polluted stormwater runoff. MS4s that choose not to implement this program can face steep fines. But that isn’t the only consequence communities may face if stormwater pollution remains unchecked.
Under the Clean Water Act’s 303(d) provisions, states are required to identify contaminated waterways and develop pollutant- specific plans in the form of a total maximum daily load (TMDL) for each pollutant. These TMDLs can help bring these waterways back into compliance.
Communities with contaminated water bodies—as defined by the 303(d) provisions—are required to become active agents in the recovery of these waterways. This could require these communities to restrict permitting of further development.
“We want communities to grow and prosper as they preserve their water resources,” says Joel Haden, TVA project manager for the TGR effort. “The TGR program helps these communities do this by building awareness among elected officials and opinion leaders of practices that can help them meet Clean Water Act obligations.”
From
Classroom to Watershed
Over the past few months, under the TGR program, Gangaware and associates have
been training Tennessee publicworks and planning professionals to deliver educational
presentations to key landuse decision makers in their communities.
TGR education and outreach materials include leave-behind brochures, “door-opening” letters, detailed maps and other geographic information systems (GIS) documents, a CD-ROM containing all course materials, and prepackaged PowerPoint presentations tailored to the needs and interests of the specific audiences within a community.
For instance, the PowerPoint presentation for agricultural groups stresses the impacts farming and other agricultural practices have on water quality, articulates agricultural best management practices, suggests ways to protect the health of streams as well as livestock, outlines management tips for pastures that improve water quality and increase profits, and details ways to control erosion and chemical runoff.
The workshops expose trainees to a range of development options that will reduce negative impacts on water resources without compromising a community’s economic health. (For specific development options that reduce negative impacts on water quality, see “TGR Endorses Informed Decisions” next column.)
As part of the workshops, Hanahan demonstrates how the prepackaged presentations provided in the course materials can be adapted to meet a community’s needs by presenting one that has been modified for a mock audience and community.
Once trained by the TGR staff, public- works and planning professionals reach out to elected officials, farmers, and other groups whose activities have an impact on water quality, including residential developers and real-estate personnel, commercial developers, and the construction industry.
A Successful Model
The Tennessee Growth Readiness project is a charter member of the University
of Connecticut’s Nonpoint Education for Municipal Officials (NEMO) program
for land-use decision makers. NEMO originally was conceived to help local officials
in three Connecticut coastal towns address the issue of nonpoint source pollution
and protect the water quality of Long Island Sound. Since its creation in 1991,
NEMO has spurred the development of similar programs in 25 states, including
the TGR program in Tennessee.
The Tennessee program grew out of a two-year effort by the program partners to adapt and pilot the NEMO program. In part, this work was funded through a grant authorized by the Clean Water Act and administered by the Tennessee Department of Agriculture Nonpoint Source Program.
The Tennessee partners crafted their own version of NEMO in 2001 and launched the pilot program in the Maryville and Alcoa communities and Knox and Blount counties.
“We’ve got a great delivery team and strong support from the Tennessee local planning assistance office and the development districts,” says Haden. “As a result, across the state, 190 planners and public works officials representing 260 communities participate in our training.”
According to Gangaware, now that pilot testing has been successful, TGR is making the training available to other Tennessee communities, especially the 80- plus that fall under the Clean Water Acts’ National Pollution Discharge Elimination System Phase II MS4 requirements.
To date, the TGR team has presented a series of 11 workshops across Tennessee, from Jackson to Johnson City and including Cookeville, Chattanooga, Columbia, Nashville, and Knoxville
* * *
For more information contact Kim Davis, WMREI, The University of Tennessee, 311 Conference Center Building, Knoxville, TN 37996-4134, or call 865-974-7847.
In the southern Appalachians, collecting ramps, one of the earliest edible wild plants to emerge in the spring, has a long tradition. In fact the practice dates back to presettlement times, when Native Americans prized this relative of the leek as a tonic, a cold remedy, and a poultice to ease the pain of bee stings.
In more recent years, Allium tricoccum, and its scarcer variant Allium burdickii, have been the focus of a relatively new tradition, ramp festivals, which are growing in popularity in areas adjacent to Great Smoky Mountains National Park and the surrounding national forests. Ramps are also finding niche markets and appearing at roadside stands, in farmers markets, and on the menus of upscale restaurants across the United States. The demand for ramps, unfortunately, threatens to outstrip the supply, as collectors dig up whole plants, roots and all. In the best of conditions, ramps take a year and a half to germinate from seed and three to five years to produce a bulb.
A BUSHEL AND A PECK
Within the boundaries of the Park, ramp collection for personal consumption
of half a peck or less, about a grocery bag full, was tolerated until recently.
Managers believed that harvesting such small quantities represented no threat
to the sustainability of the species. Managers also believed the tradition would
gradually wane. Instead, the commercial market for ramps continues to grow.
In the1980s, rangers began voicing concern that the more easily accessible sites were showing signs of damage. In 1992, one ranger found 400 plants in a single collector’s plastic grocery bag; large-scale poaching was taking an even greater toll. In April 1998, a ranger near the Greenbriar entrance to the Park apprehended two men hauling out two horse-feed sacks with 60 pounds of ramps apiece. According to Janet Rock, a National Park Service botanist who specializes in rare plant monitoring, the two bags contained nearly 1,600 ramps.
In 1989, Park managers asked Rock to design and implement a five-year study at three remote sites in the Park. This was the first actual harvest study of ramps in the United States.
“When I started this study, I was breaking new ground,” Rock says. The study was based on a model designed by researchers at the University of Quebec, who found that ramp populations are declining to extinction in southern Quebec, the northernmost range of the species. This information led to a ban on ramp harvesting in Gatineau Park.
Rock’s study was conducted at sites between 3,150 and 4,500 feet in forested coves with mixed hardwood canopy, the habitat in which the plant, a member of the Lily family, thrives. Five treatment levels of harvest were used at each test plot. The control was not harvested, while four other patches were harvested at the rates of 25, 50, 75, and 100 percent.
Results of the study showed that the ramp patch harvested just once at the lowest harvest rate of 25 percent did not recover during the term of study and that, even barring further harvesting, the patch would take more than 20 years to recover. Moreover, the collection in the experimental study consisted of plants of all sizes, whereas in actual harvesting conditions, collectors prefer the largest plants, making recovery even more unlikely. And in actual harvesting conditions, Park rangers have observed that collectors return year after year to the same sites, which are eventually decimated. This study confirmed that harvesting of ramps is not sustainable, that it should be discontinued in the Park, and that greater efforts should be made to monitor populations and enforce the ban.
As a result, the Park Service announced in 2002 that the Code of Federal Regulations, which bans harvest-ing or harming any natural resource in any national park, would be enforced. Ramps are to be protected in perpetuity, like all other plant and animal resources, under the National Park Service Organic Act of 1916. Rock says only fruits, nuts, and berries for personal consumption can be taken in the Park; any activity that injures a plant is not allowed.
Subject to review by the Park Service, however, collection of plant specimens, leaf fragments, or seeds for propagation and scientific research may be allowed. In 2002, 160 permits were issued for research projects, though none for ramps. “If someone applies to conduct research, we will evaluate the impact to the Park and its resources,” says Keith Langdon, the Park’s branch chief of inventorying and monitoring. “We frown upon collection of whole plants instead of seed propagation but may allow it if it is limited in number and the results of the study contribute to the conservation of the species.”
SHIFTING PRESSURE
Since the prohibition on ramp collection in the Park went into effect
in 2002, pressure on ramp populations in the 1.6 million acres of national forests
that surround the Park has increased.
“When the Smokies shut down ramp collection, it shifted over to the national forests,” says Jim Chamberlain, a research scientist in nontimber forest sciences with the U.S. Forest Service. “I can show you evidence of more people digging on national forest lands,” he says.
Chamberlain says the Forest Service is supportive of the groups that sponsor ramp festivals and wants to find ways to continue to support such activities on a sustainable basis.
“You have to realize the inherent difference between the national forests and the national parks,” he says. “The National Forest Service was established to provide a sustainable supply of products and to manage resources such as timber and water.”
The emphasis in recent years has switched, however, to other forest products of potential commercial value. Chamberlain says the national forests are taking the lead in finding ways to manage nontimber forest products such as ramps and medicinal herbs for sustainable harvest. (See “Nature’s Little Black Bag” on page 5.)
“With ramps, I’m looking at the relation between leaf width and bulb diameter, so we can look at the aboveground biomass and make some estimates about what’s below the ground,” he says. “Second, we need to monitor the harvest activities, permitted and unpermitted, and take a more active approach in managing these resources and working with collectors.”
The next step is for the agency to write a code of federal regulations and publish guidelines for implementing legislation to manage for nontimber forest products. “In the long term, we need to get to the point where we can cultivate and propagate these plants and manage the national forests to that end,” Chamberlain says.
***
For more information contact Janet Rock,
Great Smoky Mountains National Park, 1314 Cherokee Orchard Road, Gatlinburg,
TN 37738,
or call 865-430-4743.
AWARDS. Greg Harrell, a senior research associate with the University of Tennessee’s Energy, Environment and Resources Center (EERC), is a principle member of ALCOA’s Energy Efficiency Network Lead Team, serving as primary industrial assessor of compressed air systems, steam systems, and cogeneration systems. Through 30 assessments over the past 24 months, the five-member team has identified more than $50 million/ year in energy savings in ALCOA plants throughout the United States and five foreign countries. The team received ALCOA’s 2003 Environment, Health, and Safety Excellence Award. EERC Executive Director Jack Barkenbus, Research Leader Mary English, and Research Associate Jonathan Overly were appointed to the statewide "Tennessee Early Action Compact Advisory Committee." The Committee is evaluating measures that promise cleaner air in Tennessee and comprises 25 members from throughout the state. The Committee will provide advice to the state and the seven Early Action Compacts in Tennessee, formed to assure attainment of new, eight-hour ozone air-quality standards.
PROJECTS. The Tennessee Department of Transportation (TDOT) Senior Review Team recently announced preliminary results of a project review conducted through UT’s Center for Transportation Research (CTR) for TDOT Commissioner Gerald Nicely. EERC Research Leader Mary English served as one of eight members of the Senior Review Team. The team, led by CTR Director Steve Richards, assessed the decision processes behind 15 controversial TDOT road projects. Other UT faculty members serving on the team were Greg Reed, Tom Urbanik, Fred Wegmann, and Arun Chatterjee (all of civil and environmental engineering).
PRESENTATIONS. The U.S. Environmental Protection Agency’s Clean Air Act Advisory Committee met in October in Asheville, NC, to discuss initiatives to clear the nation’s air. EERC Research Associate Jonathan Overly, one of three presenters to the subcommittee on “Linking Energy, Land Use, Transportation, and Air Quality,” discussed the East Tennessee Clean Fuels Coalition, its goals, and how alternative fuels could improve air quality. EERC recently teamed with Tennessee- based Dale Supply Company to institute a quarterly series of “lunch-andlearn” sessions. David Doane, certified energy manager and EERC’s director of energy research, organizes sessions and serves as moderator.
PUBLICATIONS. Mary English, along with doctoral student Sean Huss (Sociology), coauthored a book chapter on “Population and Urbanization,” which will appear in A Land Imperiled: The Declining Health of the Southern Appalachian Bioregion (Knoxville: University of Tennessee Press, 2004).
