The Brent Spar Saga
What do you do with a floating piece of garbage that is 150 meters tall and 30 meters wide? That's the question which became the subject of a dramatic debate between the owners of the Brent Spar, a 65,000-ton decommissioned oil platform and the environmental activist group, Greenpeace.
After three years of studies, British permit procedures, and meetings with Scottish fishermen and environmental groups, Royal Dutch Shell, owner of the Brent Spar, came up with its two most feasible plans: horizontal dismantling, an on-shore disposal technique that would require the buoy to be turned onto its side, loaded onto a ship, and taken to a coastal area for decontamination and disassembly; and deep-sea disposal, a cheaper and technically simpler option of towing the buoy to a site in the North Atlantic and sinking it. Citing the expense, occupational health risks, technical difficulty, and possibility of accidental contamination of shallow estuarine waters during horizontal dismantling, Shell opted for deep-sea disposal. The chosen location was a mile-and-a-half-deep ocean trench, 150 miles northwest of the Outer Hebrides, an island group off the northwest coast of Scotland.
After more than a year of study, Greenpeace raised objections to Shell's plan, pointing out that, based on Shell's own reports, the Brent Spar still held 100 tons of sludge, possibly containing cadmium, lead, arsenic, oil, and PCBs; 30 tons of radioactive waste in the form of scaly deposits within the pumping system; and corrosion-reducing anodes made of zinc. Shell insisted that all the oil was drained in 1991, and that it had removed 100 tons of waste from the oil rig, including lubricating oil, batteries containing cadmium and lead, and light bulbs containing mercury, and made plans to go ahead with the sinking.
After a several-week occupation of the rig platform in April, Greenpeace claimed to have video footage and laboratory tests documenting the presence of oil and hydrocarbon-containing water in three of the six storage tanks, and oil in another, evidence that there might be as much as 5,000 tons of oil still aboard. Additional waste, including radioactive deposits, was not accessible for sampling. Greenpeace also criticized Shell's chemical manifest, which was based solely on estimates of quantities without recent empirical evidence.
Battle on the high seas. Greenpeace activists attempt to board the Brent Spar, an oil rig slated for deep sea dumping. |
According to Shell's reports, the sinking of the buoy would cause no significant effects on animal life in the area, and wastes would be contained in the immediate area. Greenpeace asserted that it would be difficult to estimate the environmental impact because toxicological data about the response of deep-sea organisms to environmental insults are not available. A recent report in the June 29 issue of the journal Nature questioned Greenpeace's reasoning, pointing out that hydrothermal vents release much larger quantities of heavy metals than the Brent Spar contains, and that some deep-ocean-floor communities rely on heavy metals as nutrients.
Aside from the environmental impact, another concern was that the sinking would set a disposal precedent. Of approximately 400 other such oil installations in the North Sea, 50 are due to be decommissioned in the next 10 years. The levels of wastes on the Brent Spar might have been used to set negligible levels of wastes, such as radioactive waste, leading to the dumping of similar levels of radioactive waste contained in items such as waste concrete rubble. In light of these considerations, Greenpeace advised that the buoy be disassembled on land.
When Shell refused to abandon its original plan, Greenpeace brought the battle to the sea, to the government, and to the gas stations. On June 12, just a day after European environmental ministers condemned Shell's planned action at the North Sea conference, Shell began towing the rig out to sea, followed closely by the Greenpeace vessel Moby Dick. Over the ensuing days, Greenpeace managed to place four activists on the rig, determined to go down with it if necessary.
Meanwhile, in Germany, Greenpeace appealed to strong environmentalist sentiment, securing the consensus of parties across the political spectrum against Shell. The North Sea forms part of Germany's northern border and is an important route for sea traffic and fishing. German Chancellor Helmut Kohl brought up the issue of the Brent Spar at the Group of Seven, an international meeting held in Canada in June. Kohl personally requested that British Prime Minister John Major refuse Shell the right to dump the rig in the North Sea. Major, a strong supporter of the original plan, refused, leaving Kohl and others throughout Europe to call for the continuation and expansion of a boycott on Shell gasoline.
Economic pressure mounted as other nations, including Denmark, Sweden, the Netherlands, and some consumers in Britain, joined the boycott that began in Germany. For three weeks in June, business at Germany's 1,728 Shell stations was reportedly down by approximately 30%, representing a loss as high as 24 million dollars. In addition, German Shell stations received numerous bomb threats and 50 cases of vandalism, including one firebombing, one shooting, and an undetonated letter bomb. Although no one was injured, Shell labeled the boycotts the result of purely political actions devoid of reason and accused Greenpeace and their other opposition of instigating a terrorist attack.
Finally, amid the waning support of the European community, Shell unexpectedly dropped the North Sea disposal plan, saying that it felt it was "in an untenable position . . . without wider support from the governments participating in the Oslo-Paris Convention." The Oslo-Paris convention recently declared a ban on deep-sea disposal of such equipment.
Norway, one of the few remaining supporters of the plan, offered safe anchorage to the rig, provided that Shell meet certain requirements. The Brent Spar is floating at a location at the northern tip of the Shetland Islands as Shell waits for results of the Norwegian permitting process, which would allow them to moor the buoy for one year in Norwegian waters while they formulate a new disposal plan. Once they do, their problems may still not be over: damaged during its construction by the buildup of differential stresses on the storage tanks, the Brent Spar faces the ongoing risk of accidents during towing, upending, and disassembly. Shell estimates that on-land disposal will cost $46 million dollars plus the possible loss of a British tax incentive, versus the original estimate of $16 million for deep-sea disposal. However, while Greenpeace acknowledges that on-land disposal will be difficult, expensive, and dangerous, they insist that the dismantling is possible using present technology and is a sounder environmental alternative.
The Cost of Living
A fish caught off the coast of Spain two years ago sold for more than what most people pay for a car. The $70,000 price tag for the 715-pound bluefin tuna (in high demand in Japan) was a harbinger of financial repercussions that will result from the human race taxing its natural resources to feed and clothe a soaring population, said Lester Brown, president of the nonprofit WorldWatch Institute, speaking at the 20th annual conference of the National Association of Environmental Professionals (NAEP).
The conference, held June 10-13 in Washington, DC, focused on such complex topics as watershed management, risk-assessment methodology, and innovative methods of preventing pollution. But Brown reminded the participants that the heart of the world's environmental problems remains a glut of people. "The world cannot continue to add 90 million people a year without getting into trouble," he said. "It's been nearly three years ago that the famine started in Somalia. In 1992, 300,000 Somalis died. It took the world just 29 hours to make up that loss. That's how fast the world population is growing."
Problems affecting availability of food may be a final wake-up call for environmental issues, Brown said. The world's oceans are being fished at their limits or beyond and are also beset by water pollution, coral reef degradation, and other environmental damage, he said. Farmers also are struggling to keep up with population growth. Land is becoming scarce, as is the water needed to grow crops. Water scarcity in China has forced farmers there to return to rain-fed farming, Brown said. And land scarcity could set back advances in more environmentally friendly energy sources, Brown noted. As food supplies dwindle and demand rises, for example, less grain will be available to make ethanol as a cleaner alternative to gasoline. The United States should adopt a national policy outlining a commitment to stabilizing world population, Brown said.
Some of the subsequent technical sessions at the conference echoed Brown's theme, specifically those dealing with sustainable development and ecosystem management. Jim Benson of the Natural Resources Conservation Service at the U.S. Department of Agriculture in Washington provided data on the impact of environmental problems on agriculture. The agency's National Resources Inventory, a study of 1.5 billion acres of nonfederal land, states that the available acreage of prime farmland fell from 339 million to 333 million acres between 1982 and 1992. Almost one out of every four cropland acres were eroding too fast to sustain soil productivity, Benson added. The NRI should help guide federal policy and provide up-to-date information on natural resource conditions, he said.
At the conference, the President's Council on Environmental Quality and NAEP awarded their third annual Federal Environmental Quality Awards, which honor federal agencies for excellence in implementing the National Environmental Policy Act, enacted 25 years ago. The Fort Worth District Army Corps of Engineers won the award for its project, a programmatic environmental impact statement of Joint Task Force Six activities along the U.S.-Mexico border. The project was organized in 1989 in response to the National Drug Control Strategy. Joint Task Force Six is a multiforce government agency charged with providing technical, logistical, operational, and engineering support to federal, state, and local law enforcement agencies throughout the southwestern United States.
The U.S. Department of Energy won the award for the continued improvement of its National Environmental Policy Act Compliance Program. Secretary of Energy Hazel O'Leary has taken bold steps to reinvent the DOE's National Environmental Policy Act program and has brought a change of culture and instilled in senior managers a commitment to openness and public participation in environmental decision-making, NAEP officials said.
NAEP, which began as a 350-member, interdisciplinary professional society in 1975, now boasts 3,300 members. It is the only overarching professional society serving the environmental professions and promotes ethical practices, technical competence, and professional standards for the environmental professions. A top goal of the group, said NAEP President Richard B. McLean, is supporting innovative and cost-effective environmental technologies.
New Rules for Medical Waste
The EPA estimates that its new proposed standards and guidelines for medical waste incinerators (MWIs) will reduce air pollution from the nation's 3,700 operating MWIs by 95% over 5 years.
EPA's proposal, Standards of Perform-ance for New Stationary Sources and Emission Guidelines for Existing Sources: Medical Waste Incinerators, implements sections 111(b) and 129 of the 1990 Clean Air Act amendments. Section 129 requires the EPA administrator to establish performance standards for MWIs. Published in the February 27 Federal Register, the proposal targets emissions of dioxins, hydrogen chloride, lead, cadmium, mercury, and fly and bottom ash emissions from MWIs. Along with commercial medical waste incineration facilities, the new regulation mainly will affect hospitals, which produce more than 70% of the 3.4 million tons of medical waste generated in the United States each year. It will also affect nursing homes, veterinary facilities, commercial research laboratories, and bloodbanks, and the estimated 700 new MWIs installed over the next 5 years.
The EPA defines medical waste as solid waste generated when humans or animals are treated, diagnosed, or immunized, and when researchers produce or test biologicals-preparations like vaccines or cultures made from living organisms and their products.
Every year in the United States, according to the EPA, hospitals generate an estimated 2.5 million tons of solid waste, 15% of which is infectious. Laboratories, clinics, and medical offices generate even more biomedical waste, which can be anything from bandages, vials, syringes, hypodermic needles, and plastic tubing to blood, laboratory cell cultures, and human and animal tissues.
Unless the waste is treated, state and local governments usually prohibit municipal landfills from accepting it, prompting hospitals to either treat infectious waste on site or ship it to a hazardous-waste facility. Consequently, many hospitals own or share incineration facilities.
David Driesen, an attorney with the Natural Resources Defense Council (NRDC), says his organization would like to see the proposal require more pollution prevention. "A trend over the last few years has been toward good pollution alternatives and, at the state level, the closing down of small, uncontrolled incinerators at hospitals in favor of better-controlled regional facilities, often with the cooperation of hospitals," Driesen says. "The measure of success for this rulemaking is whether it will accelerate that trend."
In an April 28 statement to the EPA, the Chicago-based American Hospital Association (AHA) said it supports "the enactment of reasonable regulations that are necessary to protect the environment and public health. However, the proposed regulations appear to be overly restrictive, unnecessarily costly, and burdensome," with no significant environmental improvements or reduced risks, the statement said. AHA has more than 5,000 member hospitals and health systems and 50,000 personal members.
At the EPA Emission Standards Division in Research Triangle Park, North Carolina, Rick Copland says examiners will take a close look at all comments, including those from AHA "to see how they developed their cost estimation."
Medical waste incinerators are subject to widely varying state and local regulations. An April 1990 EPA survey showed that 38 states had MWI-specific regulations or permit guidelines in place or on the drawing board. The other states regulate MWIs under less stringent general incinerator requirements.
Subpart Cc of the new regulation proposes emission guidelines and compliance schedules for states to use in developing regulations to control existing MWI emissions. The proposed guidelines establish emission limits for specific pollutants (see table) and set out additional requirements. Facilities must train and qualify MWI operators and develop and annually update site-specific training manuals for each MWI. Annual testing and monitoring must be performed to show compliance with emission limits for dioxins, particulate matter, cadmium, lead, mercury, carbon monoxide, and hydrogen chloride. "With respect to dioxins," NRDC's Driesen emphasizes, "there is evidence it is already at potentially unsafe levels in human bodies. Mercury similarly is a pollutant that accumulates, causes water pollution, and moves up the food chain. Some pollutants tend to dissipate. This group has serious health consequences. We need to reduce their amounts and avoid adding them to the environment." Most dioxin sources have not yet been identified, Driesen adds. "But the data we do have say medical waste incinerators are right up there in terms of generating dioxins."
A continuous emissions monitoring system (CEMS) would track opacity and carbon monoxide emissions. The guidelines require monthly opacity testing to determine compliance with fly and bottom ash emissions. An annual stack test would monitor emissions of other pollutants. If an MWI passed all three annual compliance tests in a three-year period, the MWI could forego testing for that pollutant for the next two years. MWI facilities must either comply with a state plan within one year after the EPA approves the plan or comply with the state plan within three years after the EPA approves the state plan if the owner/operator documents and submits measurable, enforceable steps it will take to comply with the state plan. Finally, facilities must comply with operator training and qualification and inspection requirements within one year after the EPA approves a state plan.
In addition to the provisions for existing MWIs, the proposed regulation would also cover emissions from new MWIs. The rule would regulate site-selection for MWIs built after the final rule effective date, including a requirement of comprehensive air quality analysis and analysis of the potential effect of air, ground, and water pollution on visibility, soils, and vegetation. Facilities would submit results to the EPA and state and local officials, make results available to the public, and provide for a public meeting and prepare a comment and response document.
Driesen says his organization looks to the proposed rule for pollution-prevention incentives that do more than set standards. "The proposal was weak in that regard," he adds. "We're looking for requirements that encourage recycling, incineration alternatives, and pollution prevention efforts. The proposed regulations mention alternatives but don't require that anyone do anything with regard to pollution prevention. Emission standards seem to be aimed at accommodating waste streams that could be cleaner in the first place."
General standards would probably improve things, Driesen concludes, "but they fall short of state requirements for maximum achievable emission reductions. A well-controlled facility can do a lot better than what EPA is proposing."
"Individual incinerators emitted less than our proposed standards," EPA's Copland says, "but when we set a standard it has to be achievable by all incinerators. We feel the proposed standards are as stringent as our data would support." Copland adds, "This was a proposal. No one is required to do anything yet. We are taking comments and reassessing virtually everything. The final rule could look very different from the proposal." The final rule will take effect in April 1996.
Wayne Thomann, director of Occupational and Environmental Safety at Duke University Medical Center in Durham, North Carolina, says the newest MWI proposal won't affect his facility, which began in 1992 to use "administrative controls to assure compliance with EPA's evolving regulations on chemical emissions that affect public health and the environment." Thomann says his facility no longer burns the plastics and heavy metals that release priority pollutants. In response to the EPA's 1990 Clean Air Act Amendments, he says, "We decided to change our waste mix. We didn't need to burn plastics and heavy metals. Now we won't burn anything but pathological waste, animal carcasses, and bedding." Duke now uses commercial contractors to dispose of hazardous waste. "Since we took ourselves out of the loop [for these hazardous emissions]," Thomann says, "we're doing as well or better than the emissions standards being proposed."
If the MWI standards and guidelines were to take effect as proposed, the EPA estimates the nationwide annual cost of waste incineration per unit of medical waste treated for new MWIs would increase from $136 a ton to $161 a ton. For existing MWIs, the cost of waste incineration per unit of waste treated would rise to $222 a ton from the regulatory baseline cost of $185 a ton.
In terms of costs to the hospital industry and, ultimately, to hospital patients, the EPA estimates that for new MWIs the industry would have to raise prices to cover higher waste disposal costs by an average 0.03% over current revenues of $224 billion a year. For existing MWIs, this would mean an average price increase of 0.1% over current revenues. Put another way, AHA spokesperson Alicia Mitchell estimates total capital cost requirements for compliance could be as high as $1.6 billion, and annual owning and operating costs could be as high as $344 million per year.
The EPA believes medical waste generators now operating medical waste incinerators have three choices: continue to operate their on-site incinerator and comply with the proposed emission limits, install an alternative medical waste treatment technology on site, such as autoclave, microwave or chemical treatment, or contract with a commercial medical waste disposal service for off-site treatment and disposal of medical waste. For existing MWIs, the EPA estimates 80% of facilities now burning waste on site will switch to another treatment and disposal method to avoid the cost of installing air pollution control equipment.
Selenium Secrets
An ounce of prevention is said to be worth a pound of cure, but little is understood about the mechanisms of cancer that might be targeted as prevention strategies. Researchers are looking at several naturally occurring elements and vitamins that may potentially protect against cancer. Despite a somewhat checkered past, selenium, an element obtained through the diet, may have a promising future in cancer prevention.
Selenium is widely distributed in inorganic form in soil and in organic form in certain foods. An excess or a deficiency in selenium intake can cause a variety of clinical symptoms and toxicities in humans. Most people in developed countries receive adequate amounts of selenium in its organic form (selenomethionine) found in cereals, grains, fish, and certain vegetables. Historically, selenium has been classified as a nutrient, but it is classified also as a toxin and a carcinogen. Recently, selenium has been labeled a "chemoprotective agent."
Research in the 1970s showed that selenium binds to and detoxifies poisonous levels of mercury. Mercury and other heavy metals oxidize low-density lipoproteins in the blood, a process that promotes arteriosclerosis and eventually leads to heart disease. Studies have shown that people in Japan with high levels of serum selenium who also eat mercury-tainted fish have a much lower rate of heart disease than the U.S. population.
Fish tales. Traditional seafood diets may protect against environmentally related diseases.
Research on Canadian Eskimos provides another example of the protective properties of selenium. Éric Dewailly, director of the Environmental Health Service at Quebec's Public Health Center, has studied the Inuit from northern Quebec over the past decade. The Inuit have higher than normal blood levels of lead, mercury, and polychlorinated biphenyls (PCBs), which can be especially toxic to children and fetuses (see Dewailly et al., EHP vol. 101, no. 7, p. 618 and a related article, Chan et al., EHP vol. 103, no. 7-8, p. 740). Also, the smoking rate among Inuits is approximately 65%, about twice that of southern Canadians. Surprisingly, however, the Inuit have low levels of cancer and heart disease.
Researchers believe the Inuit may be protected by their intake of such protective substances as selenium and omega-3 oil from their diet of muktuk (skin of beluga whales) and other marine animals. Dewailly explains that "Inuit whole-blood selenium levels are about 10 to 15 times the levels found in the U.S. population." Although this evidence is intriguing, some researchers question whether confounding factors such as a shorter life span may account for the difference in disease rates. Because the average life expectancy for Inuits (62 years) is slightly lower than for the U.S. population, one theory is that Inuits do not live long enough to develop certain cancers. However, because cancer incidences for a population are typically age-adjusted, this may not be a real factor.
Results of epidemiological studies are inconsistent on the protective role of selenium against chemically and virally induced cancers. In a 1993 study published in the Journal of the National Cancer Institute, selenium, in combination with vitamin E and beta-carotene, successfully protected against spread of esophageal and stomach cancer in a clinical intervention trial conducted in Linxian, China.
Studies in laboratory animals also support the protective role of selenium in cancer. Rat, mouse, and hamster models have been used to study liver, breast, colon, skin, and pancreatic cancers. A review titled "The Chemoprotective Role of Selenium in Carcinogenesis," published in the Journal of the American College of Toxicology in 1986, stated: "Of 35 studies published since 1949, 31 have shown that selenium produced an inhibitory response, whereas only 3 reports have found that there was no effect." The review continued, however, "In 1 case, selenium . . . increased pancreatic ductular carcinoma yields," indicating there is still no clear-cut case for selenium's protective role.
Most of these animal studies have used the inorganic form of selenium (selenite, selenate, or selenium dioxide). The primary concern with these compounds is that they may be toxic at doses required to achieve chemoprotection. To address this problem, Karam El-Bayoumy, associate division chief at the American Health Foundation, and his colleagues are attempting to develop novel synthetic organoselenium compounds that are chemoprotective and have low toxicity.
Results of several studies published in a review article in the November 1994 issue of Carcinogenesis show that one promising organoselenium compound from El-Bayoumy's laboratory has reduced tumors in breast, lung, and colon cancer in animals caused by several different carcinogenic agents, including one present in tobacco smoke. Requests to conduct detailed toxicology testing are now being accepted by the National Cancer Institute. Following this testing, the compound may enter phase I clinical trials, although no timetable can yet be estimated.
Computer Recycling Takes Hold
Old computers never die, they just go to the attic . . . or the basement, or the local elementary school. At least, that's where they've gone until now. But the likelihood that outdated computers will start ending up in landfills is increasingly high. According to scientists at Carnegie-Mellon University, the average computer now becomes obsolete within 12 months of production. They predict that about 150 million personal computers will be in landfills around the world by the year 2001--enough to fill an acre-wide hole three-and-a-half miles deep.
"Today, two computers become obsolete for every three purchased," D. Navin-Chandra, an assistant professor at Carnegie-Mellon, recently told Fortune magazine. "By 2005, the ratio will be 1 to 1, which means we should be able to recycle computers as fast as we make them."
The lack of a recycling infrastructure for computers poses a threat not only to municipalities faced with collecting and disposing of the computers in their landfills, but also for the manufacturers, who might be held responsible for any leakage of toxic materials from these computers. Some computers have leachable quantities of lead and other toxic materials, although they are present only in small quantities.
Computers have at least some components that are economical to recycle. Specialty recyclers like the Handy and Harman company have been involved in the disassembly and recovery of materials from computers, printers, and other electronic hardware since the early 1960s. Their business is growing at the rate of 15-20% a year.
"The principal economics with a computer is in the recovery and refurbishment of the subsystems--the hard drive, the keyboard, and occasionally the monitor," says Steven Foulk, marketing executive with Handy and Harman. "The next level involves recovery of the integrated circuits and various components including the processor and memory. The final level is the recovery of precious metals including gold and copper."
Will not compute. Rather than shelving the problem of what to do with outdated computer equipment, several companies are pushing for recycling and reuse.
Once a computer is more than 4-5 years old, Foulk says, the subsystems are generally not worth refurbishing. At that point, the value comes in "mining" the computer for its raw materials. The typical desktop computer contains about $50 worth of usable material. This includes aluminum valued at $9.37, gold at $6.45, and copper at $5.56. Unfortunately, the costs of collection, dismantling, purification, and smelting can run $45-47 per unit, making it little more than a break-even operation. Plastics, which at $12.07 per unit have the highest value of all components, present a particular problem.
"There are too many different kinds of plastics being used in most computers, which makes them difficult to separate," says Foulk. "Maybe 20 percent is recyclable, and the rest is either incinerated or landfilled."
Responding to pleas from recyclers and environmentalists, computer manufacturers are beginning to design their products with end-of-life management in mind. Two schools of design are emerging: design for the environment (DFE) and design for disassembly (DFD). IBM's Engineering Center for Environmentally Conscious Products is pioneering advances in both these fields.
"Starting in 1991, we emphasized design that used fewer materials and less energy," says J. Ray Kirby, director of the IBM center. "Within the second year, we focused on how to design to assist in recovery and recycling. Our PS/2E qualifies for the government's Energy Star Logo. It tak7es less energy to run than most PCs and the plastic cover has 25 percent recycled content."
IBM has only a limited take-back program. The company operates a number of collection centers in Europe, which has a more aggressive stance on take-back. Computers are sent to Scotland where the keyboards are melted down and remolded. In the United States, IBM is piloting some programs to evaluate the costs of take-back, but these are not yet available to all customers.
Hewlett-Packard operates product recovery centers in Roseville, California, and Grenoble, France, which together retrieve nearly 800,000 pounds of computer and related equipment each month. Products are disassembled and sorted into types of components. Reusable and resalable parts, such as computer chips, are recovered and refurbished. The remaining parts are recycled to the maximum extent possible.
Apple sponsors periodic trade-in programs for its personal-use computers through colleges and universities. Students can receive a $250 discount on a new Apple computer or printer when trading in an older model. Computers are sent to Fox Electronics in San Jose, California, which recovers the integrated circuits and sends other components to other recycling firms. Apple's most recent buy-back program netted over 15,000 computers.
Recyclers identify four major problems that must be addressed if computer recycling is to make significant inroads. First, computers need to be designed for easier disassembly, which currently runs about $20 per desktop computer in labor costs alone. Second, separation systems for mixed plastics need to be developed. Third, recycling efficiency for metals needs to be improved. And finally, recycling processes need to be developed for elements, particularly exotic elements such as rhodium and terbium, which are not currently being recycled, but which may become critical because rare elements are used in advanced computing systems.
"For recycling to be effective, the infrastructure to take computers apart has to be as big as the manufacture," says Foulk. "The infrastructure for recovery of the metals is in place. The infrastructure for dismantling and recovering subsystems that still have value is developing. Collection and transportation is in its infancy."
Measuring UV's Effects
Long-term exposure to UV-B rays, the spectrum of sunlight with a wavelength shorter than 320 nanometers, is known to contribute to a variety of human ailments including premature aging of the skin, nonmelanoma skin cancer, and cataracts. It is also suspected to play a role in melanoma skin cancer and suppression of the immune system. Stratospheric ozone is the most important factor determining the amount of UV-B radiation reaching the earth's surface. Concern about human exposure to UV-B has been increasing since decreases in atmospheric ozone were discovered over Antarctica in 1985. Unfortunately, there is no worldwide network for measuring changes in UV radiation, so there is no clear understanding of how much UV radiation is increasing in different locales, or whether such increases might be responsible for observed changes in biota. But that situation is about to change.
In coordination with the U.S. Global Change Research Program, the EPA has installed spectroradiometers--devices that will provide long-term data on the UV-B flux reaching the earth's surface--in five cities in the United States: Atlanta, Georgia; Research Triangle Park, North Carolina; Gaithersburg, Maryland; Boston, Massachusetts; and Bozeman, Montana. Data from these devices will be useful in studies ranging from the effects of UV-B flux on the incidence of cataracts to the failure of striped bass eggs to reach maturity.
The device, called a Brewer spectroradiometer, is capable of measuring radiation across the UV range in half-nanometer wavelengths. Spectroradiometers provide continuous measurements, feeding data automatically into computers inside the buildings on which the instruments are installed. Continuous measurement is crucial since most biologic effects from UV-B are sensitive to accumulated doses rather than a threshold dose. The main advantage of spectroradiometers over other UV-monitoring instruments is that the biologic effectiveness for any spectrum can be calculated. Additionally, the details of the spectrum bear vital information about the composition of the atmosphere, such as total ozone column, total oxygen saturation column, and particle scattering, all of which affect the amount of UV-B reaching the earth's surface. The relationship between these various phenomena are complex and not well understood. Ground-based UV measurements, coupled with other meteorological data such as cloud cover, are necessary to explore atmospheric changes and the resultant effects on the biosphere.
"Until now, the data has not been good enough to resolve the many issues with respect to changes in the UV-B flux," says Larry Cupett, acting director of the EPA's Atmospheric Processes Research Division. "We know that changes in the total ozone column can influence the amount of UV-B reaching the earth's surface. But is there a long-term trend? What is the influence of cloud cover, particulate scattering, and ozone in the planetary boundary layer? Until you understand all the parameters, you can't identify which ones will have long-term effects. And until we get a technique that can accurately measure UV-B, the correlations with various biological effects will be suggestive."
Project scientists estimate they will need at least 5-7 years' worth of data to begin to detect long-term changes. Data gathered from each site will be posted on the World Wide Web under the EPA's home page beginning later this year. Additional cities will be included if funding becomes available.
Menace in the Mix
New research underway at Duke University could yield clues to how chemicals used by U.S. soldiers during the Persian Gulf War may have intermingled and caused neurotoxic effects in some veterans. The combined, or synergistic, effects from three chemicals: pyridostigmine bromide, DEET, and permethrin, may have caused some of the symptoms reported by Gulf War veterans, including chronic fatigue, rashes, headaches, weight loss, and joint pain, according to Mohamed Abou-Donia, a professor of pharmacology at Duke University who is spearheading the research.
"It's a plausible hypothesis that synergism occurred," says Ernest Hodgson, head of the toxicology department at North Carolina State University, who has devoted much of his work to studying the synergism of chemicals. "That's not to say [the hypothesis] is an appropriate lead for further investigation," Hodgson cautions. "Dramatic cases of synergism are really not that common."
Abou-Donia's preliminary findings are arresting, however: they show that, when introduced alone, the chemicals caused no harmful effects on laboratory animals. However, when the chemicals were administered two or more at a time, the animals underwent significant neurological damage. Abou-Donia and his colleagues, toxicologist Ken Wilmarth and biochemist John Locklear, tested the chemicals on chickens because they are more sensitive than rats to chemicals that harm the central nervous system and because federal agencies call for the use of chickens when screening chemicals for possible neurological effects.
Findings from Abou-Donia's research, due to be published soon, may supply at least one missing link in the chain that may one day conclusively tie a number of symptoms reported by Gulf War veterans to environmental exposures they suffered during the war. Soldiers there endured environmental hardships ranging from oil well fires and infectious parasites to pesticides, insecticides, and anti-nerve gas pills originally intended to protect them. Abou-Donia's research is being funded by a grant from former presidential candidate and veterans' advocate H. Ross Perot.
Ironically, the three chemicals being evaluated at Duke were issued by the Department of Defense to protect soldiers. At the outset of the conflict, U.S. and British troops were given a 21-count package of 30-mg pyridostigmine bromide, anti-nerve gas pills that would counter the effects of potential Iraqi chemical warfare. "It shields an enzyme present in the brain and peripheral nervous system in a reversible manner, for a short period of time," says Abou-Donia, explaining how the chemical functions.
Though the DOD and a Defense Science Board Task Force on Gulf War Effects concluded in their 1994 report that the Iraqis did not use chemical or biological weapons against coalition forces, rumors of chemical warfare apparently circulated widely among soldiers throughout the conflict. According to Abou-Donia, fear prompted many soldiers to take more than the recommended dosage of pyridostigmine bromide pills. "During the war, over 50 percent of U.S. service personnel seen in the health service complained of symptoms relating to pyridostigmine bromide," Abou-Donia says.
The other two chemicals Abou-Donia and his colleagues are studying are N,N-diethyl-m-toluamide (DEET), an insect repellent, and permethrin, a liquid insecticide. According to Abou-Donia, DEET (used in a 90% concentration) was used due to concern about insect-borne tropical illnesses. Soldiers' uniforms were impregnated with permethrin, says Abou-Donia. Some veterans have reported that combat uniforms were doused with the liquid, then distributed in plastic bags. Because soldiers would presumably wear the uniforms for an extended time--a period of days, perhaps--extensive dermal contact with the permethrin would have occurred. Both DEET and permethrin have low acute toxicity, Abou-Donia says. "If the two chemicals had been given alone, they would not have caused harm," he quickly points out. In 1992, New York state banned the use of insect repellents containing more than 30% concentrations of DEET because of concerns over health effects (see EHP, vol. 102, no. 11, p. 910).
To test the combination of chemical exposures in the lab, the researchers administered pyridostigmine bromide orally and both the DEET and permethrin dermally via subcutaneous injection. Though soldiers in the battlefield would have absorbed the latter two chemicals dermally, Abou-Donia and his colleagues had to inject the chickens subcutaneously to deliver precisely measured and statistically viable quantities.
Abou-Donia's team is also investigating the hypothesis that the chemicals the Gulf War soldiers were exposed to generated a delayed toxic impact known as organophosphate-induced delayed neurotoxicity (OPIDN). OPIDN assaults both the central and peripheral nervous systems, producing symptoms such as weakness, lack of coordination, and even paralysis. After analyzing brain tissue samples from laboratory chickens, the researchers found that nerve damage was linked to the decreased activity of an enzyme present in tissues, neurotoxic esterase. The team is searching for biomarkers present in the animals' blood that will show nervous system damage, and are comparing animal blood samples with those from affected veterans. "If we could find a biomarker, then we could find a treatment for existing populations," Abou-Donia said.
Researching synergism. Duke's Mohammed Abou-Donia is investigating whether the illnesses plaguing Gulf War soldiers are the result of exposure to chemical mixtures.
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While Abou-Donia's research sheds light on the connection between environmental exposures and some medical symptoms associated with what is unofficially referred to as Gulf War Syndrome, it does not explain why some individuals appear to be more sensitive to the chemical effects.
"We would like to try to see if, in fact, we could identify a population segment that is naturally predisposed to chemical sensitivity," says Abou-Donia describing MCS, a medical phenomenon that is widely acknowledged, yet little understood, even by scientists and physicians closest to the issue. "Maybe there is a genetic variant we need to identify," Abou-Donia suggests. A more complete understanding of genetically dependent chemical sensitivity could be useful should the DOD deploy soldiers in future military operations.
One scientist interested in studying Persian Gulf veterans with symptoms resembling multiple chemical sensitivity is physician Claudia Miller, an expert on MCS and an assistant professor of environmental and occupational medicine at the University of Texas Health Science Center at San Antonio. As a staff physician at the Houston VA's Persian Gulf Regional Referral Center, Miller evaluates the health of Gulf War veterans.
According to Miller, certain people may have genetically determined metabolic differences that make them susceptible to chemical sensitivity--a phenomenon that falls into a new area of study called ecogenetics. "We rely heavily on epidemiological studies, which are based on crude estimates of past exposure," Miller says of her work with Gulf War veterans and other MCS patients. "We're trying to correlate [chemical exposures] with health problems," a process that is error-prone because it relies on anecdotal information from patients, but which Miller calls "invaluable" for the information it supplies.
Of the veterans she has evaluated who have unexplained illnesses following their service in the Persian Gulf, a large portion have reported the onset of new chemical intolerances which commonly include diesel exhaust, solvents, gasoline, tobacco smoke, hairspray, and fragrances. Miller refers to this as a toxin-induced loss of tolerance (TILT), a term she prefers to chemical sensitivity "because available data on MCS patients and Gulf War veterans point away from MCS as a syndrome, but perhaps toward what may be an emerging new mechanism or theory of disease." Describing TILT, Miller says, "Once their tolerance level is exceeded, they don't respond normally to low-level exposures." These veterans exhibit the typical two-phase response observed in MCS patients: during the induction phase, loss of tolerance occurs following an acute chemical event or a less-acute series of events. This loss of tolerance can involve any of a wide range of chemicals such as medications, caffeine, foods, and other chemically unrelated substances. In the triggering phase, patients experience symptoms when they are exposed to tiny amounts of such common substances, but these responses overlap in timing, thereby masking any individual reaction to a single chemical. What is relevant to the Gulf veterans' illnesses about TILT, says Miller, is the fact that a wide range of environmental agents (solvents, pesticides, combustion products, etc.) appear to be capable of initiating this process.
According to Miller, further research on chemically sensitive Gulf War veterans will require studies conducted in a controlled environmental medical unit--a hospital-like environment built and furnished with materials that don't emit chemical vapors and equipped with an efficient air filtration system. Only in such an environment, Miller says, could subjects be observed to see whether they improve, and if so, then be re-exposed to very low levels of chemicals, one at a time, under double-blind, controlled conditions and then evaluated for symptoms.
Studies on Gulf War health effects are as politically significant as they are scientifically important. Confirmation of a link between chemical exposures and negative health effects would allow affected Gulf War veterans to receive compensation under the veterans' disability compensation program.
The U. S. Department of Veterans Affairs established three research centers--in Boston; East Orange, New Jersey; and Portland, Oregon--in October 1994 to study how environmental and toxic hazards may affect health. Among six research projects underway at the Boston center is a study to examine the relationship between war-time exposure and chronic fatigue, chemical hypersenstitivity, and post-traumatic stress disorder. At the New Jersey center, scientists are gathering information on illnesses suffered by Gulf War veterans, hoping to examine a characteristic symptom profile and connect certain risk factors with the development and progression of unexplained illnesses. Researchers at the Portland center are screening veterans for medical, chemical, or biological markers that may confirm exposure and disease, as well as studying how chemical agents, including pyridostigmine and pesticides, may affect the nervous system.
EHPnet
Recent events surrounding the successful attempt by the environmental group Greenpeace to force the Royal Dutch Shell oil company to dismantle a decommissioned oil rig rather than sink it in the North Sea focused attention on the issue of environmental assaults on the world's oceans. In a perhaps less dramatic but more detailed effort, a major new traveling exhibition at the Smithsonian Institution's National Museum of Natural History is also aimed at the issue of oceans.
Described as "the culmination of a four-year effort to study and understand environmental issues affecting the health of the world's oceans," the exhibit, Ocean Planet, opened on 22 April 1995. After eight months in Washington, DC, Ocean Planet will travel to 11 American cities through the end of the millennium. For those who may not be able to visit the exhibit, a companion exhibit is available on-line via the World Wide Web.
Upon entering the on-line exhibit, users are presented with the floor plan of the Ocean Planet Exhibition as currently presented at the Museum of Natural History. From this map users can go to any part of the exhibit hall by clicking on the name of the room they want to visit or take a special tour designed by the museum's curator. The exhibit traces the global benefits that oceans provide in terms of food and health products, recreation, and economic growth, as well as the impact of human activity on ocean ecosystems. Examples of this impact detailed in the exhibit show that polar ecosystems are no longer beyond the reach of human activity: tourism, commercial fishing, and pollution are putting pressure on populations of penguins, whales, seals, and krill; intertidal zones may support as many as two thousand species, but these interfaces between land and sea are in jeopardy from coastal development, land-based runoff, and ocean pollution; and oil pollution disasters make headlines, but hundreds of millions of gallons of oil quietly end up in the seas every year, mostly from nonaccidental sources such as road runoff.
Hyperlinks in the exhibit "rooms" such as ocean science, oceans in peril, and resources provide brief but informative descriptions of topics of environmental interest. The ocean science portion of the exhibit provides discussions ranging from recent discoveries of hydrothermal vents, previously unknown marine animals, and volcanic fields, to how ocean currents are tracked and the relationship between oceans and climate. The oceans in peril section provides overviews of marine pollution, divided into subtopics such as oil pollution, toxic contaminants, non-point-source pollution, and mining and dumping; habitat destruction, which deals with the effects of deforestation and the loss of wetlands on oceans; fishing issues such as overfishing, ecosystem changes, and pollution by bombs and poison; and global change issues including climate change, ozone depletion, and population.
Perhaps the most useful section of the exhibit for environmental researchers is the resources room. This section includes an extensive list of hyperlinks to oceanographic and environmental resources on the Internet ranging from the Scripps Institution of Oceanography, the Woods Hole Oceanographic Institute, the National Oceanic and Atmospheric Administration, and the Distributed Ocean Data System to the International Arctic Buoy Program, the Save Our Seas home page, and the Small Islands Information Network. Users interested in ocean issues should dive into this exhibit at URL:http://seawifs.gsfc.nasa.gov/ocean_planet.html.
Last Update: April 2, 1997