We have found the sources of hazardous waste and they are us.
U.S. EPA booklet, Everybody's Problem: Hazardous Waste, 1980
It's the environment, stupid. At least, that seems to be the conclusion of a paper published in the October 1998 issue of BioScience that asserts that approximately 40% of the world's deaths can be attributed to environmental factors. The paper was written by David Pimentel, a professor of ecology and agricultural sciences at Cornell University in Ithaca, New York, and 11 graduate students who took Pimentel's special year-long course on environmental policy. Says Pimentel, "The reason that I suggested this investigation was my interest in environmental and population issues. The disease situation turned out to be more serious than we had anticipated."
Pimentel says his team arrived at the 40% figure based on the following facts: 1) more than 3 billion people are malnourished, with many dying directly and indirectly from malnutrition; 2) smoking is on the rise worldwide; 3) approximately 4 billion people are exposed to toxic smoke through their cooking fires; 4) heightened UV light exposure is causing more skin cancers; 5) humans are exposed increasingly to the 100,000-plus chemicals in use worldwide; 6) radon exposure is increasing worldwide; and 7) water and air pollutant exposure is increasing worldwide. "In our view," says Pimentel, "the 40% figure is conservative; it could be much higher."
Malnutrition. Malnutrition is endemic to areas of the world marked by political unrest, poverty, soil degradation (due to overfarming and unchecked urban expansion), and overpopulation. The World Health Organization has estimated that some 6-14 million people worldwide die each year from malnutrition. Of that figure, some 2 million die of vitamin A deficiency, and approximately 1-2 million deaths can be attributed to anemia, or iron deficiency. Due to food shortages around the world, vitamin A and iron consumption continue to decline in many developing nations.
Smoking. Smoking has been cited as one of the two major underlying causes of premature death, and the number of smokers is rising globally. Today, smoking causes approximately 3 million deaths around the world each year; by the year 2020, predicts one study, smoking will claim some 10 million lives worldwide. In the United States alone, deaths due to lung cancer rose 400% between 1950 and 1990.
Cooking fires. The smoke of cooking fires fueled by wood, coal, and other organic material contains not only particulate matter but also carcinogenic chemicals such as benzene, formaldehyde, and polycyclic aromatic hydrocarbons. A 1993 study of Indian households that cook over open fires found indoor particulate matter concentrations that were as much as 200 times higher than the maximum standard for U.S. homes. According to one World Bank study, fuelwood cooking smoke causes the death of approximately 4 million children worldwide each year.
Skin cancer. By one estimate, every 1% decrease in the ozone layer increases UVB radiation by 1.4%, and the incidence of skin cancer is increasing accordingly. Some North American white populations, whose lighter skin pigmentation puts them at greater risk for developing skin cancer, are experiencing a 30-50% jump every five years in the prevalence of the condition. The number of new cases of skin cancer in the United States has quadrupled over the past 20 years, resulting in nearly 10,000 deaths per year.
Chemical exposures. According to a 1994 World Resources Institute report, the United States uses at least 20 billion kg of hazardous chemicals each year, and nearly 10% of the chemicals in use today are known to cause cancer. Between 1989 and 1996, the number of pesticide poisonings reported in the United States nearly doubled. Worldwide, deaths and chronic illnesses due to pesticide poisoning number about 1 million per year.
Radon exposure. Radon, a radioactive gas that seeps up from the ground, is becoming a greater health risk as modern houses are constructed to be better insulated and more airtight. Radon exposure is thought to be a significant cause of lung cancer in the United States, and may be causing as many as 14,000 deaths per year. In Sweden, says the paper, radon concentrations in houses have risen as much as fivefold over the past 30 years.
Water and air pollution exposure. About 1.2 billion people lack access to clean water. In developing nations, as much as 95% of untreated sewage is dumped directly into rivers, lakes, and seas that are also used for drinking and bathing. Agricultural and erosion runoff can carry toxic chemicals to drinking water supplies. According to the report, 1993 air pollution levels in the world's 20 largest cities far overshot regulatory standards due to increased industrial and automobile emissions. In Los Angeles, for example, the average exposure to carcinogens found in automobile exhaust may be as much as 5,000 times greater than the EPA standard.
While the Cornell paper paints a discouraging picture of life on earth today, Pimentel hopes some good will come of the bad news. "We hope that our study will encourage more up-to-date reporting on diseases," he says.
Annual Review of the Environment
The association between nonionizing radiation and breast cancer, the human health implications of phenolic compounds in plants, and the impact of global climate change are among the environmental health issues given in-depth treatment in the annual review issue of EHP Supplements, the sister publication to EHP. This year's review issue, due out this month, contains 17 original peer-reviewed monographs on some of the past year's most pressing environmental health topics. Each review article contains extensive background information, as well as an author summary and analysis of the newest developments in the field.
Cover of 1999 January Supplement
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For the 1999 review issue, Leeka I. Kheifets of the Electric Power Research Institute in Palo Alto, California, and C. Chantal Matkin of Stanford University in California examine the association between nonionizing radiation (electric and magnetic fields, or EMFs) and breast cancer. Because breast cancer occurs more often in industrialized countries, some researchers have theorized that it may be attributable to the increased use of electric power. Kheifets and Matkin assess more than 35 residential and occupational epidemiological studies that investigated the association between EMFs and breast cancer. Although most of the data do not unequivocally support an association between EMFs and breast cancer, the scientists point to the limited statistical power of the studies, as well as the possibility of misclassification and bias present in much of the existing data, as reasons why such an association should not yet be ruled out. "Given the ubiquitous nature of EMF exposure and the high incidence of breast cancer," they write, "even a small risk will potentially have a substantial public health impact." This review comes on the heels of the Working Group Report, funded by the NIEHS Electric and Magnetic Fields Research and Public Information Dissemination Program, that ruled that EMFs may be considered possibly carcinogenic to humans.
Otto Daniel and colleagues from the Swiss Federal Office of Public Health and the Swiss Federal Institute of Technology, both in Zürich, study the toxic and beneficial human health effects of certain phenolic compounds. These compounds are produced in plants to serve a number of purposes, including repelling herbivores, pigmentation, protection against UV light, and biocidal defense against bacteria and fungi. External stimuli such as chemical stress from heavy metals and pesticides can alter the chemical composition or quantities of phenolic compounds in a plant; depending on its concentration, chemical structure, and any external modulation, a given phenolic compound might be either toxic or beneficial to humans. The scientists examined three such compounds. Resveratrol, which is found in grapes and peanuts, has been found to inhibit the synthesis of substances that cause blood clotting, possibly offering protection against heart disease and thrombosis. Flavonoids, which are found in almost every food or beverage of plant origin, act as antioxidants, inhibit blood coagulation, promote vasodilation, and have anti-inflammatory effects--benefits that appear to outweigh their variable mutagenic properties. Furanocoumarins, which are found in plants such as limes and celery, can cause phototoxic burns but have also been harnessed for use in psoralen UVA therapy, which is used to treat skin conditions such as psoriasis and cutaneous T-cell lymphoma.
Janice Longstreth of the Waste Policy Institute in Washington, DC, and the Institute for Global Risk Research in Bethesda, Maryland, discusses the regional impact of global climate change in the United States. She says that many public health officials feel that any increases in health effects related to global climate change will be easily absorbed by the health care systems in place, but Longstreth warns that this position may be dangerously shortsighted. She discusses the possible effects of higher temperatures, increases in ground-level ozone and other air pollutants, changes in vector, host, and infectious agent habitats, rising water temperatures, and increases in extreme events such as hurricanes and tornadoes. She also discusses how such changes may vary among regions, possibly burdening some areas more than others with a shortfall between health care needs and resources.
A second public health paper in the review issue looks at methods for maintaining control of pathogens in drinking water while simultaneously ensuring that disinfection by-products do not present health risks. Other papers cover cellular mechanisms such as the known signal transduction pathways that regulate cell cycle progression and DNA stability mechanisms, the relationship between toxic environmental chemicals and apoptosis, the manner in which metabolic genotypes affect individual susceptibility to cancer, and the role of the Bcl-2 gene family in prostate cancer. Four papers address the roles of cholinesterases and acetylcholine in the developing nervous system, and others discuss current issues in toxicology, including the development of short-term estrogenicity tests for identifying hormone disruptors, the toxicology and chemistry of toxaphene compounds, the field of geographic modeling and its role in environmental epidemiology studies, and the latest data on waterborne diseases caused by bacterial, protozoal, and viral pathogens.
EHP Supplements is published six times each year (including the annual review issue). More information is available on ehpOnline at http://ehp.niehs.nih.gov.
Indoor fungal contamination has been shown to produce allergies in building occupants. While fungi have also been suspected of playing a role in sick building syndrome (SBS), a health condition that results from poor indoor air quality, few studies to date have been able to verify this link. A recent study, however, links SBS with elevated indoor levels of the fungi Penicillium and Stachybotrys, both of which have been implicated in respiratory diseases such as asthma and pulmonary hemosiderosis. The research, which was published in the September 1998 issue of Occupational and Environmental Medicine, is the most comprehensive SBS study to date, having examined more buildings than any previous study.
David Straus and colleagues at Texas Tech University Health Sciences Center in Lubbock conducted a 22-month in-depth study of 48 schools that had reported concerns about health and indoor air quality to the indoor air quality company with which the university researchers are affiliated. The schools are located along the Gulf of Mexico and the Atlantic seaboard of the United States.
The researchers disseminated a questionnaire to the staff of the schools asking about health complaints, timing patterns of symptoms, and particular areas of the schools in which staff members experienced symptoms. About 30% of all staff reported symptoms or complaints, most commonly nasal drainage, congestion, and itchy, watery eyes. Most of the staff said they experienced these symptoms only while in the building. More than half of those who reported symptoms also noted increased incidences of respiratory infections such as tonsillitis, bronchitis, and, in some cases, pneumonia.
The researchers also measured humidity, particulate matter, carbon dioxide, and chemicals such as formaldehyde, nitrogen dioxide, hydrogen sulfide, sulfur dioxide, and carbon monoxide, both indoors and in the outdoor areas surrounding the schools. They examined the schools' heating, ventilation, and air conditioning (HVAC) systems, and took swab samples and air samples at sites that had been wetted and showed mold growth.
In some of the schools, Straus's team discovered that the major factor that correlated with the health complaints was increased indoor levels of Penicillium and Stachybotrys. Straus says that, ideally, the amount of fungi inside a building should be much lower than that outside. In many of the schools, the levels of the two fungi were much higher inside than outside. These schools were found to conduct very little HVAC maintenance and many had active water leaks, creating the damp conditions in which fungi thrive.
Twenty schools showed significant increases in the amounts of Penicillium species in indoor air samples of complaint areas. The mean indoor relative humidity in these areas was higher than in noncomplaint areas and higher than outdoor relative humidity. At 11 schools, the researchers found heavy growth of Stachybotrys molds on swabs taken from under damp carpets and vinyl wall coverings and on walls. This organism produces a mycotoxin that has been shown to affect the central nervous system and cause damage throughout the body.
In the remaining schools, Straus found that the fungal ratios of indoor and outdoor air samples were not significantly different. However, swab samples in many of these schools detected heavy growth of the Penicillium species as well as another type of fungi, Cladosporium. According to the report, these findings indicate possible fungal growth inside the schools and a potential indoor air quality problem.
Once remedial action was completed in the schools, the number of health complaints decreased. Remedial action involved replacing building materials that showed physical deterioration, cleaning surfaces showing microbial contamination and treating them with an approved disinfectant, and cleaning the HVAC systems in accordance with National Air Duct Cleaners Association standards. The researchers followed up with air and swab samples within 60 days of the cleaning and again six months later. They found that fungal ratios had returned to acceptable, normal levels, and that the percentage of staff complaining of symptoms had dropped from 30% to less than 3%.
To prevent fungal contamination, Straus says, the solution is very simple: "Get water out of the building and properly maintain the HVAC system." He says that building maintenance is also important because problems such as roof leaks and broken pipes also increase humidity, allowing fungi to thrive.
Straus says the team did not disseminate the surveys to students due to the difficulty of administering them to children and the unreliability of children's responses. He says, however, "We believe that children are affected even more [by the fungi] because they are still growing." While research on the effects of fungi on children's health is sparse, a 1993 case in which experts believed that a strain of Stachybotrys caused adverse health effects in many infants spurred public interest. Several babies in the Cleveland, Ohio, area who were found to have been exposed to the fungus developed pulmonary hemosiderosis. This disease is marked by bleeding of the lungs--which can lead to coughing up blood, nose bleeds, chronic cough and congestion, and anemia--and caused the death of many of the infants.
A newly developed antimicrobial agent known as BCTP may offer scientists a powerful weapon against a range of viruses, spores, and bacteria, including the culprits behind two of the deadliest diseases known to humans--anthrax and influenza. BCTP has been shown to kill up to 90% of anthrax spores in mice and 99.6% of influenza A virus in in vitro tests. These findings were presented at the 38th Interscience Conference on Antimicrobial Agents and Chemotherapy, held 24-27 September 1998 in San Diego, California.
Bacillus anthracis
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Anthrax is caused by the bacterium
Bacillus anthracis. It is generally a disease of four-legged animals, but can spread to humans in three ways. Cutaneous infection occurs through handling the hides and wool of infected animals, and is characterized by skin ulcers and swelling of the lymph glands. This form can be fatal if not treated with antibiotics. Respiratory infection is caused by inhaling
B. anthracis spores, which causes severe respiratory distress and shock and almost always results in death. Gastrointestinal infection occurs through eating the undercooked meat of infected animals. This form causes severe inflammation of the gastrointestinal tract, nausea, vomiting of blood, and diarrhea, and results in death in 25-60% of cases. While anthrax infection usually occurs in agricultural regions, the spores are also part of the biological weaponry arsenals of a few nations.
Influenza |
Influenza A is responsible for most of the severe flu epidemics that occur worldwide each winter. The 1918-1919 epidemic of Spanish flu, which caused 20 million deaths worldwide, and the 1957-1958 run of Asian flu, which resulted in 70,000 deaths in the United States, were both strains of influenza A.
Bacterial spores are notoriously difficult to fight because the hardness of their casings makes them invulnerable to typical antimicrobial agents. But with just a few simple ingredients, BCTP slices through that Gordian knot. Soybean oil and water form an emulsion of tiny lipid droplets that fuse with the anthrax spore, causing it to revert to its active--and therefore softer and more vulnerable--bacterial state. This makes the spore sensitive to disruption by the detergent Triton X-100 and the solvent tri-n-butyl phosphate, ingredients that also stabilize the emulsion. D. Craig Wright, president of the biologics and research division at Novavax, a biopharmaceutical company in Rockville, Maryland, and one of the inventors of BCTP, says that Triton X-100 and tri-n-butyl phosphate are also used in the plasma industry to purify blood products such as hemoglobin. Spores have yet to demonstrate tolerance to the treatment. This may be due to BCTP's unique mechanism of action, which also works on other organisms with protective coatings, such as enveloped viruses. "It's so simple," Wright says, "people wonder why others haven't done this before--we've wondered that ourselves."
BCTP has been shown to be effective in dilutions as high as 1 part per 1,000 parts culture medium. In tests on recent BCTP formulations, says James R. Baker, Jr., director of the University of Michigan Center for Biologic Nanotechnology in Ann Arbor and director of the animal studies, BCTP kills 95% of anthrax spores within one hour. Preclinical mucosal-surface studies have been completed, and Phase I human studies for mucosal tolerance are being developed to ensure that BCTP won't irritate the nasopharyngeal passage. Baker and colleagues are also launching a series of animal tests for inhalatory use. Baker says, "Because of [BCTP's] efficacy in other areas, we are hopeful it will also be effective in preventing disease in the lungs."
As a defense against biological warfare, the treatment would need to be applied topically within one hour of exposure, and could also be applied to the skin for prophylactic use, for instance, prior to going into battle. As a safeguard against influenza, Baker envisions a nasal spray that could be inhaled every 4-6 hours during flu season or when going into a crowded situation, such as at an airport or school. Other applications in development include hand creams, mouthwashes, and lotions that kill bacteria and viruses on contact.
The scientists are also working with the National Institute of Child Health and Human Development on contraceptive applications using BCTP, including a vaginal cream that not only kills sperm, but also kills sexually transmitted disease organisms on contact. Amazingly, considering the amount of damage BCTP can do to infectious organisms, it is apparently nontoxic and nonirritating to humans, animals, and the environment. Says Wright, "We're designing products that aren't [even] as noxious as the detergent you use to wash your clothes."
Over 50 years ago, the U.S. Department of Energy (DOE) was given the task of quickly developing the technology and materials that would establish the United States as a nuclear superpower. Partly due to the DOE's success in this venture, conditions in the world have changed, and the department's emphasis on weapons production has declined. Now the DOE faces the challenge of cleaning up the environmental mess that remains at many of its old production facilities. The task is a daunting one; there are over 2,100 contaminated sites at the department's Los Alamos, New Mexico, facility alone.
Many places that were once central to weapons manufacture are now turning into environmental laboratories where remediation techniques are tested on some of the country's worst pollution problems. The DOE Office of Environmental Restoration was created in 1989 to find innovative and efficient ways to clean up DOE facilities. Among the many remediation technologies being tested by this office are a robot that uses microwave energy, a vacuum to remove contaminated concrete surfaces, a device that freezes large sections of soil to immobilize pollutants, and a device that sends enough electricity through polluted soils to melt them into a glass-like material.
The DOE is also putting a new emphasis on communicating its activities to the public. Information about the many projects of the Office of Environmental Restoration can be found on its Web site at http://www.em.doe.gov/er/. Following the Environmental Restoration Program link on the office's home page will take users to an overview of DOE restoration activities. Included here is a link to Technical Aspects of the DOE Environmental Restoration Program, where the DOE describes its pollution challenges along with the dozens of technologies that have been developed to meet them.
Also linked to the Environmental Restoration Program page is a guide to the 132 sites that the DOE is now cleaning up. The DOE Environmental Restoration Sites by State link takes users to a map highlighting the 31 states where these activities are taking place. Clicking on any state or on Puerto Rico will take users to a list of restoration sites in that area, each linked to a description of the cleanup work being done there.
More information about the office's projects and policies can be found by following the Management of the DOE Environmental Restoration Program link, also on the Environmental Restoration Program page. Here, users will find links to the Office of Environmental Restoration's strategic plan and to information about public participation in the office's cleanup projects.
The Decommissioning of Facilities link on the management page takes users to descriptions of DOE structures that are being destroyed or removed for environmental reasons. For example, the site contains a description of how the Office of Environmental Restoration demolished the Oak Ridge K-25 Site Powerhouse that once supplied electricity to run the Manhattan Project, turning the site into a large, grassy field.
Another link on the management page, Program Progress, takes users to the electronic version of EM Progress, the newsletter of the DOE's environmental programs. The Technology Information Exchange link on the management page is connected to information on workshops and conferences, and to the electronic version of the TIE Quarterly, a newsletter about DOE technology exchange.
Many of these pages, such as the Technology Information Exchange page, can be accessed directly from the Environmental Restoration home page by using the drop-down menu bar located near the center of that page. More detailed information about many of the DOE's restoration projects is available from the department's various field offices, all of which have home pages that can be accessed via the DOE Operations/Field Offices link on the Environmental Restoration home page.
Last Updated: January 25, 1999