CHAPTER 8
TOXINS IN EVERYDAY LIFE

Many of the substances naturally found in the environment or released by modern, industrialized society are harmful to humans and other living creatures. Common toxins include heavy metals (lead, cadmium, aluminum, mercury, and manganese), chlorine, organic chemicals (such as pesticides and herbicides), and radiation.

These substances may be found in the home, workplace, or backyard, in the food and water people eat and drink, and even in medications. Most of the chemicals attacked in Rachel Carson's 1962 book Silent Spring (Boston: Houghton Mifflin) are still used in the United States, and some that have been banned have been replaced by substances even more toxic.

WHY ARE TOXINS TOXIC?

A toxin is a substance—bacterial, viral, chemical, metal, fibrous, or radioactive—that poisons or harms a living organism. A toxin may cause immediate, acute symptoms such as gastroenteritis, or cause harm after long-term exposure such as living in a lead-or radon-contaminated home for many years. Some toxins can have both immediate and long-term effects: Living in an environment with cigarette smoke may trigger an acute asthma attack or, after many years' exposure, it may contribute to lung cancer. Although the effects of a toxin may not show up for years, these effects may, nevertheless, be serious. Toxins are often grouped according to their effect on living creatures. They may be called carcinogens, mutagens, and teratogens:

• A carcinogen is any substance that causes cancerous growth.
• A mutagen is an agent capable of producing genetic change.
• A teratogen is a substance that produces malformations or defective development.

The risks posed by environmental contamination may not be blatantly obvious. For example, people or animals with impaired immune systems and who are exposed to these contaminants may take longer (or even be unable) to recover from infectious diseases. Tracking this problem to environmental pollutants, however, can be difficult.

CHEMICAL TOXINS

Hundreds of chemicals released into the air, water, and the food chain are harmful to the environment—to humans as well as other living things. Under the Federal Insecticide, Fungicide, and Rodenticide Act (61 Stat 163; amended 1988, PL 100-532), the Environmental Protection Agency (EPA) is charged with reviewing chemical studies and taking appropriate action, including banning dangerous substances. The EPA may regulate the manufacture, importation, processing, distribution, use, and disposal of any chemical that poses a risk to human health or the environment. Regulatory tools used by the EPA range from requiring a substance to bear a warning label, to placing a total ban on production and importation. The EPA reviews more than 2,000 new chemicals each year, and research and testing continually find new substances to add to this list.

Among the most common contaminants identified as harmful are DDT, kelthane, lindane, some synthetic pyrethroids, dioxins, polychlorinated biphenyls (PCBs), furans, some heavy metals such as lead and cadmium, and some plastics. Solvents are common in industrial applications but are also found in such products as furniture polish, bathroom tile cleaners, disinfectants, and shoe polish.

Of the thousands of chemicals currently produced in the United States, many have yet to be tested to see whether they might cause cancer, birth defects, infertility, or abnormal growth in children. Some observers charge that the EPA follow-up on warnings of adverse effects has been slow and, sometimes, has enabled dangerous pesticides to remain on the market.

Toxic Release Inventory

In 1984 a deadly cloud of chemicals was released from the Union Carbide pesticide plant in Bhopal, India, following an explosion in the plant. The methyl isocyanate gas killed approximately 3,000 people and injured 200,000 others. Shortly after, a similar chemical release occurred in West Virginia, where a cloud of gas sent 135 people to the hospital with eye, throat, and lung irritation complaints. There were no fatalities. Such incidents fueled the demand by workers and the general public for information about hazardous materials in their areas. As a result Congress passed the Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA; PL 99-499).

The EPCRA established, among other things, the Toxics Release Inventory (TRI), a publicly available database (http://www.epa.gov/tri) that contains information on toxic chemical releases by various facilities. More than 650 toxic chemicals are on the TRI list.

Certain manufacturing facilities (which are called "original" industries under the program) have had to file TRI reports since 1987. In 1998 the program was expanded to include certain facilities within a group of industries called the "new" industries. These "new" industries include metal and coal mining, electric utilities burning coal or oil, chemical wholesale distributors, petroleum terminals, bulk storage facilities, Resource Conservation and Recovery Act subtitle C hazardous water treatment and disposal facilities, solvent recovery services, and federal facilities. The requirements only apply to facilities that use certain thresholds of toxic chemicals and that employ ten or more full-time workers.

The 2001 Toxics Release Inventory (TRI) Public Data Release Report was published in July 2003. Facilities reported a total of 6.16 billion pounds of chemical releases in 2001. On-site releases to air, land, and water accounted for 91 percent of all releases, while off-site releases (when a facility sends toxic chemicals to another facility where they are then released) accounted for the remainder. Most (56.2 percent) releases were to landfills or surface impoundments. Air emissions accounted for just over 27 percent of the total. Releases via underground injection to deep wells and releases to surface water accounted for nearly 4 percent each. (See Figure 5.18 in Chapter 5.)

In 2001 the metal mining industry accounted for the largest amount of total emissions (45 percent), followed by electric utilities (17 percent), and the chemical industry (9 percent). (See Table 8.1.) The 20 chemicals with the largest releases in 2001 are listed in Table 8.2. These 20 chemicals accounted for the vast majority (88 percent) of the total releases. The metal compounds were primarily released via landfills or some other type of land release.

The organic chemicals, acids, and chlorine were mainly released in air emissions, while nitrate compounds were primarily discharged to surface waters.

The TRI report for 2001 focused on a group of chemicals called persistent bioaccumulative toxic (PBT) chemicals. These are toxic chemicals that persist in the environment a relatively long time and accumulate in the tissues of plants, animals, and humans. The TRI describes releases of 454 million pounds of PBT chemicals in 2001, including dioxins, lead, mercury, polycyclic aromatic compounds, PCBs, pesticides, and other complex organic compounds. (See Table 8.3.)

Pesticides and Herbicides

Pesticides are chemicals used to kill or control insects. Herbicides are chemicals used to kill or control vegetation, particularly weeds. These are a unique group of chemicals because they are specifically formulated to be toxic (to some living things) and are deliberately introduced into the environment. Due to these two facts they are closely regulated. The EPA reviews every pesticide for every particular use.

According to the August 2002 EPA report Pesticides Industry Sales and Usage: 1998 and 1999 Market Estimates by David Donalson et al., approximately 70 percent of all pesticides sold in the United States are used for agricultural purposes. Agricultural pesticide use costs $11 billion annually. Every dollar spent on agricultural pesticides is estimated to return about $4 in crops saved. Agricultural dependence on chemicals developed since the 1940s. Prior to that time natural methods, such as crop rotation, mechanical weed control, and other practices, were used to control pests and weeds.

Agricultural use of pesticides grew steadily through the 1960s and 1970s and leveled off at about one million pounds of active ingredient per year. This level has remained relatively constant since the 1980s. Pesticide use in the 1960s centered around organochlorines, including DDT, aldrin, and toxaphene. The environmental dangers and health hazards of these chemicals gradually led to their replacement with other types of pesticides, mainly pyrethroids.

Pesticides have been detected in surface waters, groundwater, and even rainfall. In 2001 the U.S. Geological Survey (USGS) announced that testing performed for the National Water Quality Assessment Program had found at least one pesticide in more than 95 percent of stream samples and in more than 60 percent of shallow agricultural wells. Although the concentrations were generally low and below drinking water standards, their effects on the environment and human health are not known for certain.

The study also found sediments contaminated with persistent organochlorine pesticides, such as DDT, dieldrin,

and chlordane, at more than 20 percent of agricultural sites tested. Use of these pesticides has been restricted for several decades, but many of them are "persistent," which means they do not easily degrade. DDT, in particular, can latch tightly onto soil particles, where it can persist for decades. DDT is also bioaccumulative, which means it can work its way from a nonliving medium, such as dirt, to a plant or animal. Since it is not easily broken down by metabolization within living creatures, DDT moves up the food chain as plants and animals containing DDT are consumed by others.

While pesticides have important uses, studies show that some cause serious health problems at certain levels of exposure. For example, pesticide by-products have been linked to breast cancer in humans. Researchers have found that breast tissue from some women with malignant breast tumors contained more than twice as many PCBs and DDE (a component of the pesticide DDT) than are found in the tissue of women who do not have cancer. Scientists indicate that the carcinogen is stored in body fat, making obesity a risk factor for breast cancer.

In general the level of persistent toxins, including pesticides, has declined in humans and wildlife since the 1970s. Newer pesticide compounds are often more toxic than the older types of pesticides but they are generally designed to be less persistent in the environment and tend to cause fewer chronic problems such as birth defects. However, even pesticides originally believed safe are sometimes found to be harmful. In June 2000 researchers announced that recent tests of the pesticide dursban, a very commonly used chemical in residences, found the substance to be harmful, and many applications were withdrawn from the market. Ironically, dursban was often used as a substitute for chlordane, a chemical also withdrawn from use after being discovered to be harmful.

Fear of agricultural toxins has contributed to a rise in the interest in "organic" foods. The federal government's National Organic Program defines organic agriculture as that which excludes the use of synthetic fertilizers and pesticides. More importantly it strives for low environmental impact and enlists natural biological systems—cover crops, crop rotation, and natural predators—to increase fertility and decrease the likelihood of pest infestation.

AGENT ORANGE.

Beginning in 1962 approximately 19 million gallons of herbicides were sprayed over South Vietnam, primarily by aircraft, to defoliate vegetation used as cover for enemy troops in the Vietnam War. In 1969 studies linked chemicals in one of these herbicides, Agent Orange (named after the orange band used to mark the drums it was stored in), to birth defects in laboratory animals. Use of the defoliant was subsequently stopped in 1971. However, Vietnam has estimated that more than one million of its citizens were exposed to the spraying, and tens of thousands of Americans who served in the war are also believed to have been exposed to the chemical, which is a form of dioxin. (In 1994 the EPA affirmed the health danger posed by dioxin.)

Title 38 of the United States Code prohibits veterans from suing the government for injuries suffered while in the military. However, many Vietnam veterans have sued the manufacturers of Agent Orange for damages because of health problems experienced since their return from Vietnam. In 1979 a number of claimants filed a class action suit, In re Agent Orange Product Liability Litigation, which was settled out of court in 1987 for $180 million. The final funds in the case were distributed in 1992. Additional suits against the manufacturers have been attempted but have been prohibited by the courts. The most strongly fought of these legal battles, Ivy v. Diamond Shamrock, was supported by the attorneys general of all 50 states. The Supreme Court, however, refused to hear the arguments and the case ended in 1992. The court decreed that the issue was res judicata (the matter is settled).

The Department of Veterans Affairs sponsored a study of Agent Orange and announced its findings in 1996. The veterans' illnesses were grouped into four categories: (1) those that have a positive association with the herbicide; (2) those for which there is suggestive, but not conclusive, evidence of a link; (3) those for which there is insufficient evidence to make a determination; and (4) those for which there is little or no evidence of an association. The report also emphasized the need for further study. The illnesses that the study positively linked to herbicide use were soft-tissue sarcomas (a form of cancer), non-Hodgkin's lymphoma, Hodgkin's disease, and the skin disease chloracne. The second category included respiratory cancers, prostate cancer, multiple myeloma, acute peripheral neuropathy (nerve numbness or weakness), and spina bifida (a congenital deformity of the spine) in children of veterans. The federal government has generally agreed to pay medical claims on those illnesses.

Endocrine Disrupters—Environmental Hormones

Medical and scientific researchers are increasingly linking chemical compounds known as organochlorines to the endocrine systems of humans and wildlife. The endocrine system—also called the hormone system—is made up of glands located throughout the body, hormones that are synthesized and secreted by the glands into the bloodstream, and receptors in the various target organs and tissues. The receptors recognize and respond to the hormones. The function of the system is to regulate the many bodily processes, including control of blood sugar, growth and function of the reproductive systems, regulation of metabolism, brain and nervous system development, and development of the organism from conception through adulthood and old age.

Substances that interfere with these processes are called "endocrine disrupters." Although some occur naturally—for example, plant-derived hormones—most appear to be man-made. Disruption of the endocrine system can produce certain genetic, reproductive, and behavioral abnormalities in humans and wildlife; increases in several types of cancer not related to smoking or age; malformations; and nervous system disorders.

Endocrine disrupters are sometimes referred to as "environmental estrogens" because they are so widely dispersed in the environment that they turn up in rain water, well water, lakes, and oceans, as well as in foods consumed by birds, fish, animals, and humans. Some scientists worry that organochlorines mimic or block the action of natural estrogen, thereby disrupting the endocrine system.

Some effects of certain estrogenic compounds have been well known for some time. Among these are the eggshell thinning and cracking that led to the population decline of the American bald eagle; the reproductive abnormalities of women exposed in utero to diethylstilbestrol, a synthetic estrogen prescribed between 1948 and 1971 to prevent miscarriages; and reported declines in the quantity and quality of sperm in humans. In 1996 researchers at the National Biological Service, in a study of Columbia River otters, found a direct correlation between the level of chemicals and pesticides in the otters' livers and the size of the males' genitalia.

Only recently, however, have researchers begun to realize how many compounds in the environment are estrogenic. More than 50 of these endocrine-disrupting chemicals have been observed to disrupt the hormone or reproductive system, but the remainder of the 85,000 chemicals currently in use remain to be studied. Among them are many herbicides, pesticides, insecticides, and industrial cleaning compounds. Many such compounds have been banned in the United States. Nonetheless, they persist in the food chain for many years and accumulate in animal tissue. Moreover, many of these chemicals continue to be used in developing countries.

Researchers in North America and Europe are studying the possibility of a link between environmental estrogens and the occurrence of birth abnormalities, Alzheimer's disease, sterility in both males and females, hyperactivity in children, neurological illnesses, and many cancers. Both men and women appear to be susceptible to endocrine disruption. In men, some studies show that estrogenic compounds affect the development of the Sertoli cells in the testicles. These cells secrete masculinizing hormones that regulate sperm production, the descent of the testicles, and the development of the urethra.

Because of the potentially serious consequences of human exposure to endocrine-disrupting chemicals, Congress included specific language on endocrine disruption in the Food Quality Protection Act of 1996 (PL 104-170) and Safe Drinking Water Act Amendments of 1996 (PL 104-182). The first mandated the EPA to develop an endocrine-disrupter screening program (EDSP), while the latter authorized the EPA to screen endocrine disrupters found in drinking water. In May 2002 the EPA presented its latest report to Congress on the program's progress. The agency plans to implement the EDSP by setting screening priorities for various chemicals and by establishing uniform laboratory tests for determining which chemicals affect humans similarly to naturally occurring hormones.

Chlorine

Chlorine is a gaseous element first isolated in 1774 by chemist Wilhelm Scheele. The gas has an irritating odor and, in large concentrations, is dangerous. It was the first substance used as a poisonous gas in World War I. It can be liquefied under pressure and is usually transported as a liquid in steel bottles or tank cars.

The use of chlorine to disinfect water supplies is one of the greatest public health success stories of the twentieth century. First used to purify water in the early 1900s, chlorine is, by far, the world's primary water disinfectant and is indisputably valuable in preventing the spread of disease. It is inexpensive, effective, and available nearly everywhere. It is credited with banishing typhoid fever, cholera, and dysentery from the United States and elsewhere. About three-fourths of all U.S. drinking water is chlorinated to kill parasites, viruses, and bacteria, while most of the rest is treated with a combination of chlorine and ammonia.

Researchers, however, are trying to determine if there is any connection between chlorine in drinking water and bladder and rectal cancer in humans. When chlorine is added to water containing organic matter, it produces byproducts (such as chloroform) that are suspected of causing harm to humans and other species. Environmentalists contend that chlorine is responsible for a thinning ozone layer and for causing reproductive malformations in aquatic species and cancer in humans.

Many sources claim that reducing or eliminating chlorine in water would cost many lives. Although the body of evidence seems to show a slight increase in cancer risk from chlorine by-products, most scientists consider the risk not "statistically significant" and believe that the risks to public health would be far greater if chlorine were to be reduced or eliminated.

Although researchers are investigating alternatives to chlorination, none have been found as effective and economical. Ozonation is used by some municipal systems, because ozone is an even more powerful disinfectant than chlorine. Ozonation is widely used in Europe. However, ozone is costly to generate, and the effects of ozonation by-products are largely unknown. Use of ultraviolet radiation has been found effective against bacteria in water, but is less effective against viruses and has no effect on cysts and worms. In addition, alternative disinfectants do not provide the residual protection of chlorine-based treatment; they must be used in combination with chlorine or chlorine derivatives to provide a complete disinfection system.

Lead

Lead is a naturally occurring metal. Exposure to lead in the United States is relatively widespread, because the metal was commonly used in many industries prior to the 1970s. Exposure to even low levels of lead can cause severe health effects in humans.

SOURCES OF LEAD EXPOSURE.

Mined along the eastern seaboard since 1621, lead created an important industry, providing bullets, piping, and a base for paint. Because of its malleability, it was valued as a conduit for water. The use of wallpaper steadily declined with the almost universal use of paint, not only for protecting surfaces, but also for interior decorating. "White lead" paint was sold as the best thing to use on interior and exterior surfaces. In cities teeming with millions of new immigrants, the glossy, durable finish of white lead-based paint meant walls could be easily washed. In 1922 a General Motors researcher discovered that the addition of lead to automobile fuel reduced the "knocking" that limited power and efficiency in car engines.

Many structures are still covered by old lead paint. Nearly three-quarters of all U.S. homes constructed before 1980 contain some lead paint. The EPA reports that lead paint poses little danger if stable. But when renovations are made that involve sanding or stripping paint, the old paint may become hazardous. Certain ceramics and crystal ware, especially those made in foreign countries, still contain unacceptable levels of lead. In 1996 researchers announced that ingredients used to manufacture some miniblinds could be toxic to humans because they contain lead. Lead can be found in many other places as well, including weights used for draperies, wheel balances, or fishing lures; seams in stained-glass windows; linoleum; batteries; solder; gun shot; and plumbing. Test kits and laboratories that test for lead can now check questionable items and locations for the presence of the heavy metal.

Most of the lead in water comes from lead pipes and lead solder in plumbing systems. A 1992 EPA report revealed that 20 percent of the nation's large cities exceeded government limits for lead in drinking water. By 1993 all large public water-supply systems were required to add substances such as lime or calcium carbonate to their water lines to reduce the corrosion of older pipes, which releases lead.

REDUCING LEAD EXPOSURE.

As early as the late 1890s medical reports concerning problems with lead began to appear. In 1914 the first U.S. case of lead poisoning was reported, although the cause was undetermined. Scientists eventually began to link lead poisoning to lead paints and, as World War II ended, began to address the problem. In the mid-1960s medical reports documented the connection of lead poisoning to both auto emissions and paint.

In 1971 Congress passed the Lead-Based Poisoning Prevention Act (PL 91-695), restricting residential use of lead paint in structures constructed or funded by the federal government. The phasedown of leaded fuel in automobiles began in the 1970s. This effort was not to safeguard health but to protect cars' catalytic converters, which were rendered inoperable by lead.

In an effort to protect families from exposure to the hazards of lead-based paint, Congress amended the Toxic Substances Control Act (TSCA; PL 94-469, 1976) in 1992 to add Title IV, entitled "Lead Exposure Reduction." Title IV directs the EPA to address the general public's exposure to lead-based paint through regulations, education, and other activities. A particular concern of Congress and the EPA is the potential lead exposure risk associated with housing renovation. The law directs the EPA to publish lead hazard information and make it available to the general public, especially to those undertaking renovations.

Also in 1992 Congress passed the Residential Lead-Based Paint Hazard Reduction Act (PL 102-550) to stop the use of lead-based paint in federal structures and to set up a framework to evaluate and remove paint from buildings nationwide. In 1996 Congress once again amended the TSCA, adding section 402a to establish and fund training programs for lead abatement and to set up requirements and training of technicians and lead-abatement professionals.

BLOOD LEAD LEVELS.

Lead is highly toxic, causing harm to the brain, kidneys, bone marrow, and central nervous system. Levels as low as ten micrograms of lead per deciliter of blood can have serious health effects in infants, children, and pregnant women. (See Figure 8.1.)

Lead is a cumulative poison. For people who are exposed to it every day, over time, it begins to accumulate in the body. At very high levels of exposure (now rare in the United States), lead can cause mental retardation, convulsions, and even death. More commonly, exposure occurs at very low levels over an extended period of time.

The Centers for Disease Control and Prevention (CDC) monitors blood lead levels (BLLs) of children and adults. Since the 1970s the concentrations of lead measured in blood samples of children aged five and under have declined dramatically. (See Figure 8.2.) However, the EPA's Draft Report on the Environment 2003 notes that lead poisoning is still a "serious environmental hazard in young children in the U.S." This is particularly true for urban areas. The EPA reports that in 2001 slightly more than 10 percent of the children screened for lead in Chicago had elevated blood levels of the metal. The percentage has fallen dramatically since 1996 when it exceeded 25 percent. On a nationwide basis the EPA estimates that approximately 2 to 3 percent of children have elevated BLL.

Many scientists believe that the federal standards for exposure should be lowered, and, in fact, some researchers believe there is no safe level for lead. The CDC believes that effects on the central nervous system of children begin at ten micrograms per deciliter, and the greater the BLL, the higher the risk. The CDC recommends that if many children in a community have BLLs above ten micrograms per deciliter, community-wide lead poisoning prevention activities should begin. The Occupational Safety and Health Administration requires that a worker be removed from a workplace if his or her BLL reaches 50 micrograms per deciliter, although two Harvard School of Public Health studies released in 1996 found kidney damage and hypertension correlated with lead levels in bone below ten micrograms per deciliter.

DOES LEAD CONTRIBUTE TO DELINQUENCY?

A 1996 University of Pittsburgh Medical Center study of 800 male public school students found that, even after taking into account other predictors of delinquency, such as socioeconomic status, boys with higher lead levels were more likely to engage in antisocial acts. A direct relationship was found between the amount of lead in boys' leg bones and reports from parents, teachers, and the children themselves of criminal or aggressive behavior.

Fertilizers

The United States is the largest producer of fertilizers for domestic use and export, and American farmers are the most productive in the world, producing crops for domestic demand as well as for export to other countries. Agriculture exists in every state, but is concentrated in the Midwest. Although many different crops are farmed in the United States, corn, soybeans, wheat, and hay account for 75 percent of total crops in 2002. (See Figure 8.3.)

The U.S. Department of the Interior defines a fertilizer as any substance applied to soil to enhance its ability to produce plentiful, healthy crops. Fertilizers are natural or manufactured chemicals that contain nutrients known to improve the fertility of soils. Nitrogen, phosphorus, and potassium are the three most important of these nutrients; some scientists also consider sulfur a major nutrient for plant health. The EPA estimates that 90 percent of all fertilizers used contain nitrogen, phosphorus, and to a lesser extent, potassium.

The use of fertilizers sky-rocketed following World War II. Between 1960 and 1980 fertilizer use increased from approximately seven million tons per year to nearly 23 million tons per year. Fertilizer use declined during the 1980s, but then began to increase again, exceeding 20 million tons per year by the year 2000. The USGS estimates that approximately 12 million tons of nitrogen are applied to the land each year from commercial fertilizers. An additional seven million tons of nitrogen are applied as manure. These two sources are blamed for most of the nitrogen entering watersheds across the country.

Overfertilization of crops can cause excess chemicals to leach into surface and groundwater. Runoff of rain and irrigation waters washes nutrients (like nitrogen) into streams, rivers, and lakes. Excessive nutrients are a problem in surface waters because they cause conditions called eutrophication and hypoxia. Eutrophication occurs when nutrients stimulate the rapid growth of algae and aquatic plants. When these plants and algae die, bacteria in the water decompose them. This depletes the amount of dissolved oxygen in the water—a condition called hypoxia. Fish and other aquatic creatures require dissolved oxygen to live and thrive. Hypoxic areas become "dead zones" in the environment.

Nitrate (NO₃) is a common form of nitrogen found in water. The EPA has monitored the nitrate load in the country's major rivers since the 1950s. The data show a disturbing trend, particularly in the Midwest, where fertilizer use and soil erosion rates are high. The nitrate load in the Mississippi River increased from approximately 250,000 tons per year in the early 1960s to approximately one million tons per year in 1999. The result has been the development of a massive hypoxic area near the mouth of the river in the Gulf of Mexico. Figure 8.4 shows how this area grew in size between 1985 and 2002. The data reflect midsummer measurements, because that is the time of year when hypoxia is at its worst.

FLUORIDE

Fluoride was first added to drinking water in 1945 to control dental caries and prevent tooth decay. Dental caries is an infectious, communicable disease in which bacteria dissolve the enamel surface of a tooth. Left unchecked, the bacteria may then penetrate the underlying dentin and soft tissue, resulting in tooth loss, discomfort, and even acute infection throughout the body. At the beginning of the twentieth century, dental caries was common in the United States and most developed countries. Failure to meet the minimum standard of having six opposing teeth was a leading cause of rejection from military service in both world wars.

Dental caries declined greatly during the second half of the twentieth century, and many people attribute the decline to fluoridation of the public drinking water supply and the addition of fluoride to toothpastes and mouth washes. By 2000 approximately 57 percent of the U.S. population received drinking water that was fluoridated. (See Figure 8.5.) This is in addition to a small percentage of the population that has access to naturally fluoridated water. Groundwater and surface waters naturally contain about 0.1 to 0.2 parts per million (ppm) of fluoride. The recommended level of fluoride in water to prevent tooth decay is 0.7 to 1.2 ppm.

The widespread use of fluoridated water and dental aids has ensured that virtually everyone in the United States has been exposed to fluoride. The CDC estimates that fluoride has reduced tooth decay in children by as much as 40 to 70 percent and in adults by 40 to 60 percent. Water fluoridation is believed to be especially beneficial in low-income areas where residents often have less access to dental-care services and other sources of fluoride. Consequently, the CDC rates the fluoridation of drinking water as among the top ten greatest public health achievements of the twentieth century.

Critics say that the benefits of fluoride have been grossly overestimated and the hazards largely ignored. They point out that fluoridation of drinking water is not done in much of western Europe, yet those regions have experienced the same declines in dental caries seen in the United States. There have been long-standing concerns about the negative effects of fluoridation. Many communities have rejected fluoridation of their drinking water when the issue was presented for a vote. Worries continue about the possible links between fluoridation and dental fluorosis (mottling of the teeth), skeletal fluorosis (accumulation of excessive fluoride in the bones), kidney disease, birth defects, and cancer. Research as of 2004 has not been conclusive.

ASBESTOS

Asbestos is the generic name for several fibrous minerals that are found in nature. Very long and thin fibers are bundled together to make asbestos. First used as a coating for candlewicks by the ancient Greeks, asbestos was developed and manufactured in the twentieth century as an excellent thermal and electrical insulator. The physical properties that give asbestos its resistance to heat and decay have long been linked to adverse health effects in humans. Asbestos is found in mostly older homes and buildings, primarily in indoor insulation.

Asbestos tends to break into microscopic fibers. These tiny fibers can remain suspended in the air for long periods of time and can easily penetrate body tissues when inhaled. Because of their durability, these fibers can lodge and remain in the body for many years. No "safe" exposure threshold for asbestos has been established, but the risk of disease generally increases with the length and amount of exposure. Diseases associated with asbestos inhalation include asbestosis (scarring of the lungs), lung and throat cancers, malignant mesothelioma (a tissue cancer in the chest or abdomen), and nonmalignant pleural disease (accumulation of bloody fluid around the lungs).

In May 2003 the CDC released its sixth annual Work-Related Lung Disease Surveillance Report 2002. The report notes that 1,265 people died in 2002 from asbestosis. (See Figure 8.6.) This value is up from less than 100 recorded in 1968. In total, 10,914 people have died from asbestosis between 1990 and 1999. The vast majority of the deaths have occurred among white men aged 55 and older. Most were plumbers, pipe fitters, and steamfitters. Construction accounted for, by far, the greatest proportion (24.6 percent) of asbestosis deaths; second was ship/boat building and repairing (6.0 percent). Death from asbestosis usually occurs only after many years of impaired breathing.

Asbestos was one of the first substances regulated under section 112 of the Clean Air Act of 1970 (CAA; PL 91-604) as a hazardous air pollutant. The discovery that asbestos is a strong carcinogen has resulted in the need for its removal or encapsulation (sealing off so that residue cannot escape) from known locations, including schools and public buildings. Many hundreds of millions of dollars have been spent in such cleanups.

Under the CAA, asbestos-containing materials must be removed from demolition and renovation sites without releasing asbestos fibers into the environment. Among other safeguards, workers must wet asbestos insulation before stripping the material from pipes and must seal the asbestos debris in leak-proof containers while still wet to prevent the release of asbestos dust. The laws of most states have specific requirements for asbestos workers.

A number of legal convictions have resulted from improper and illegal asbestos removal. In many cases the convicted companies had hired homeless people or teenagers to clean up asbestos without advising them that they were dealing with asbestos and without training them in proper handling methods. In response to those cases the Department of Justice and the EPA joined with the National Coalition for the Homeless to issue an advisory to be posted in homeless shelters around the United States. The advisory warns about the dangers of asbestos and cautions workers to be on guard for employers who offer work tearing out old asbestos without providing adequate notice, equipment, and training.

Some observers believe that asbestos poses less risk to humans than previously thought, and suggest that asbestos is less harmful than smoking, drug and alcohol abuse, improper diet, or lack of exercise. They contend that Americans can live safely with asbestos—given careful management procedures—and do not need to spend huge sums of money attempting to remove it completely. In fact, the EPA recommends that asbestos found in good condition be left alone, because "disturbing it may create a health hazard where none existed before."

According to the USGS Mineral Commodity Summaries, January 2004, there was no asbestos production in the United States in 2003. The last U.S. asbestos mine closed in 2002. Approximately 6,000 metric tons of asbestos were imported into the country during 2003. Canada supplied 96 percent of the imported asbestos. U.S. demand for asbestos peaked in the 1970s, when it reached 800,000 tons. By 2003 U.S. demand had dropped to 6,600 tons, a level not seen since the 1800s. Most (80 percent) of the asbestos consumed in 2003 was used in roofing products. Gaskets accounted for another 8 percent, followed by friction products with 4 percent.

World production of asbestos in 2003 was around 2 million metric tons, with Russia as the leading producer, followed by China and Canada. World production has dropped since it peaked in 1975 at 5 million metric tons. Growing pressure to ban asbestos around the world is expected to keep pushing markets downward.

RADIATION

Radiation is energy that travels in waves or particles. Radiation exposure comes from natural and human-made sources. People are exposed to natural radiation from outer space (cosmic radiation), the Earth (terrestrial radiation and radon), and their own bodies. According to the U.S. Nuclear Regulatory Commission, these sources account for about 82 percent of the average person's radiation exposure. (See Figure 8.7.) Radon is, by far, the largest source of radiation exposure, at 55 percent. Human-made sources, mostly medical devices and electromagnetic equipment, account for 18 percent of a person's average radiation exposure.

Radon

In 1984 a worker in a nuclear plant triggered a radiation contamination alarm as he entered the plant to work. Since the alarms were intended to check for contamination as workers left the plant, plant officials were amazed. Investigations discovered the source of the worker's contamination was radon present in extraordinarily high amounts in his home.

Radon is an invisible, odorless radioactive gas formed by the decay of uranium in rocks and soil. This gas seeps from underground rock into the basements and foundations of structures via cracks in foundations, pipes, and sometimes through the water supply. Because it is naturally occurring, it cannot be entirely eliminated from homes.

Although there is no federal regulation addressing radon in indoor air, the EPA recommends that a resident take action if levels reach or exceed four picocuries per liter (pCi/L). The average indoor radon level is 1.25 pCi/L; the average outdoor level is 0.4 pCi/L. The EPA estimates that there are at least six million homes—one in 15 nationwide—with levels greater than four pCi/L, and 100,000 with levels greater than 20 pCi/L. The radon content in most homes can be reduced to 2 pCi/L or less by using devices such as specially designed fans that prevent radon from seeping into a house.

Radon inhaled into the lungs undergoes radioactive decay, releasing particles that damage the DNA in lung tissue. In June 2003 the EPA published its latest estimates of radon-related deaths in EPA Assessment of Risks from Radon in Homes. The report estimates that radon causes an estimated 21,000 deaths from lung cancer each year—the second leading cause of lung cancer after smoking. A synergistic effect has been noted: when radon levels are high in a home where a smoker resides, the likelihood of that person contracting lung cancer is greatly increased.

The EPA has proposed voluntary guidelines calling for builders to install protective measures in hundreds of thousands of new houses across the country to prevent radon from seeping in. The EPA recommends the testing of homes, which is generally quite inexpensive; home test kits are also available to homeowners. Radon contamination is addressed under the Superfund Amendments and Reauthorization Act of 1986 (PL 99-499).

The Indoor Radon Abatement Act of 1988 directed the EPA to identify areas of the country with the potential for elevated levels of indoor radon. The EPA assessed 3,141 counties in terms of geology, aerial radioactivity, soil permeability, foundation type, and indoor radon measurements. Each county was assigned to one of three zones based on its predicted average indoor radon screening level:

• Zone 1—predicted level greater than four pCi/L
• Zone 2—predicted level of two to four pCi/L
• Zone 3—predicted level less than two pCi/L

The EPA map of radon zones is shown in Figure 8.8. The map is not intended to indicate which homeowners should test their homes for radon, but to provide a general guide to state and local organizations dealing with radon abatement. The EPA cautions that homes with elevated levels of radon have been found in all three zones.

RADON IN DRINKING WATER.

In addition to exposure through the air, humans can also contact radon in drinking water. Radon gas can dissolve and accumulate in groundwater such as that found in wells. The EPA estimates that only about 1 to 2 percent of radon comes from drinking water. However, ingesting radon-contaminated drinking water can lead to the development of internal-organ cancers, primarily stomach cancer—although the risk is smaller than that of developing lung cancer from radon released to the air from tap water. The National Academy of Sciences report Risk Assessment of Radon in Drinking Water (1999), a study mandated by the Safe Drinking Water Act Amendments, estimates that radon in drinking water causes about 169 cancer deaths a year; 89 percent of those are caused by breathing radon released into the air from tap water while 11 percent are caused by consuming water that contains radon.

Not all water contains radon. Surface waters—such as rivers, lakes, or reservoirs—usually do not carry radon because the radon tends to evaporate before it has a chance to reach residences. Underground sources such as groundwater, however, may contain radon. Those who get water from a public water system that serves 25 or more year-round residents may obtain an annual water quality report that tells where the water comes from, what is in that water, and whether or not radon was found.

As of April 2004 there is no federally enforced drinking water standard for radon. The EPA has proposed two alternatives to the states and water agencies. The first is a maximum contaminant level of 300 pCi/L for radon in drinking water. The second alternative is a standard of 4,000 pCi/L if the state or water agency also implements a program to reduce indoor air radon. Neither proposal is popular with drinking water agencies, and the EPA continues to review the radon rule. A final ruling is expected by December 2004.

For homeowners who get their water from private wells—which would not be regulated—radon in the water can be reduced by using a carbon filter or aeration devices that bubble air through the water and carry radon gas out through an exhaust fan.

Electromagnetic Fields

Earth produces electromagnetic fields (EMFs) naturally, such as during thunderstorms and deep within the planet's molten core. Electricity also occurs naturally in the human body where it can be measured by electroencephalograms of brain wave activity, or electrocardiograms of heart rhythms.

Electric power is a fact of life in America and the developed world. Many consumer and industrial products use some form of electromagnetic energy. While the danger of electric shock is well known, another concern has arisen about electric power—does it cause certain types of cancer, particularly leukemia and cancer of the central nervous system?

One type of electromagnetic energy that is of increasing importance worldwide is radio frequency (RF) energy, which includes radio waves and microwaves. RF energy is used for a wide array of applications including television broadcasting, cellular telephones, pagers, cordless phones, radio communications for police and fire departments, amateur radio, and satellite transmissions. In the United States the Federal Communications Commission (FCC) authorizes or licenses most RF telecommunications activities. Noncommunications uses of RF energy include microwave ovens, radar, and diathermy (the delivery of heat to body tissues for medical or surgical purposes).

The spectrum of electromagnetic waves ranges from extremely low-frequency energy to X-rays and gamma rays, which have very high frequencies. Frequency is the number of waves passing a given point in one second. (See Figure 8.9.) All humans are exposed to EMFs at some time during the course of a day, either from natural sources or sources produced by humans. Human-produced sources include electrical items found in the typical home or office. Most people are exposed to some level of EMF daily and that level can differ at different times of the day. (See Figure 8.10.)

Scientists have known for years that exposure to high levels of RF radiation can be harmful because of the ability of RF energy to heat biological tissue rapidly (this is the principle by which microwave ovens work). Two areas of the body, the eyes and the testes, are known to be particularly vulnerable to RF heating. RF radiation, even in low levels, has caused cataracts and sterility in laboratory rabbits.

In 1996 the U.S. Public Health Service reviewed the scientific data on EMFs and determined the following:

In total, the epidemiological data on both residential and occupational exposures show a moderate risk of cancer, generally between 1.1 and 3.0 times, for adults and children exposed to magnetic fields. This is not extremely large relative to other known risks (for example, the smoking-related risk of approximately 10 or the asbestos-related risk of 5). However, what is unusual about magnetic field exposures is that they are universal. Virtually all of us are exposed.… This means that (a) the observed risk may be underestimated because we cannot identify a truly unexposed comparison group; (b) because of the widespread exposure, even a small risk may result in a large number of individual cancers.

The Public Health Service concluded that "the cost of mitigation [cleanup] already instituted far exceeds the health protection offered, and mitigation of other environmental risks is more important. From a cost-benefit view only limited, low-cost mitigation should be considered."

In its 1999 Questions and Answers about Biological Effects and Potential Hazards of Radiofrequency Electromagnetic Fields, the FCC reported: "Environmental levels of RF energy routinely encountered by the general public are far below levels necessary to produce significant heating and increased body temperature. However, there may be situations, particularly workplace environments near high-powered RF sources, where recommended limits for safe exposure of human beings to RF energy could be exceeded. In such cases, restrictive measures or actions may be necessary to ensure the safe use of RF energy."

Nonetheless, some scientists have continued to suggest that exposure to electric and magnetic fields generated by electric power is responsible for certain cancers (particularly among children), reproductive dysfunction, birth defects, neurological disorders, and Alzheimer's disease. Some activist groups allege the hazards to be so great that they have called for the closure of schools and other public facilities near power lines, and restructuring of the entire power delivery system. EMFs are even cited as causing decreases in property values. Some utilities, with equally strong beliefs, claim there is no proof of risk.

In response to concern about the risks of EMFs, in 1992, under the Energy Policy Act of 1992 (PL 102-486), Congress authorized the Electric and Magnetic Fields Research and Public Information Dissemination Program. The program mandated that the National Institute of Environmental Health Sciences (NIEHS), the National Institutes of Health (NIH), and the U.S. Department of Energy (DOE) research any possible link between EMFs and health. In 1998 an international panel of 30 scientists met to consider the evidence. In 1999 the panel issued its findings in Health Effects from Exposure to Power-Line Frequency Electric and Magnetic Fields.

The report found that the evidence was lacking to prove EMFs were a "known human carcinogen" or "probable human carcinogen," and thus EMFs did not warrant aggressive regulatory action. However, a majority of the members concluded that exposure to power-line frequencies is a "possible human carcinogen." The NIEHS concluded that EMF exposure cannot be recognized as entirely safe because of weak scientific evidence that exposure may pose a leukemia hazard. However, because virtually everyone in the United States uses electricity and is thus exposed, the panel recommended research into ways to reduce exposure. The researchers found no indication of increased cancer incidence in experimental animal studies. The strongest evidence of any connection between EMF exposure and cancer came from observations of human populations, although the scientists noted that some other factor could explain the findings, especially since the correlation was weak, at best.

In 1998 the FCC studied EMF emission levels of cellular phones, vehicle-mounted antennas, and fixed transmitting antennas used for such devices. In Information onHuman Exposure to Radiofrequency Fields from Cellular and PCS Radio Transmitters, the FCC reported that a human would have to remain within a few feet of a main transmitting beam for extremely long periods of time to be exposed to levels of RF energy in excess of recognized safety levels. In addition, the study noted that, regarding vehicle antennas, vehicle occupants are effectively shielded by the metal auto body, especially when the antennas are mounted in the center of the roof or trunk. The study yielded similar results for handheld cellular devices—exposures vary greatly depending on use. Nevertheless researchers continue a number of programs to study EMFs.

As reported in "Exposure to Power-Frequency Magnetic Fields and the Risk of Childhood Cancer," (Journal of the American Medical Association, February 2000) the American Medical Association (AMA), after conducting a study of the possible link between EMFs and childhood leukemia, found no evidence that exposure to EMFs increased the risk for childhood cancer.

In June 2002 researchers at Finland's Radiation and Nuclear Safety Authority announced that exposure to cellular phone radiation had been shown to increase activity in human cell proteins grown in the laboratory. More research was recommended to determine the seriousness of these changes and their possible health effects, particularly in the brain.

The huge growth in cellular phone use has brought renewed attention to the potential dangers of EMF exposure, particularly since the phone is held so close to the brain. More than 140 million Americans were cellular phone subscribers in 2003, compared to only 16 million in 1994. Worldwide subscribership is expected to reach two billion by 2006. In May 2001 the U.S. General Accounting Office (GAO) recommended that the FCC improve cellular phone testing and urged both the FCC and the Food and Drug Administration (FDA) to improve consumer information regarding EMF exposure and related health issues.

The FCC requires wireless phones sold in the United States to demonstrate compliance with human exposure limits for radiofrequency energy. The value used to describe the relative amount of this energy absorbed by a person's head while using a wireless phone is called the Specific Absorption Rate (SAR). The FCC safety limit for wireless phones is 1.6 watts per kilogram. Consumers can look up the SAR for a particular phone model using an FCC identification number printed on the case of the phone. Instructions for using the SAR database are available at http://www.fcc.gov/oet/rfsafety/sar.html.

TOBACCO

Tobacco use remains the leading preventable cause of death in the United States, causing more than 440,000 deaths each year and resulting in an annual cost of more than $75 billion in direct medical costs. Nationally, smoking results in more than 5.6 million years of potential life lost each year.

—Centers for Disease Control and Prevention, Atlanta, GA [Online] http://www.cdc.gov/tobacco/issue.htm [accessed May 7, 2004]

The federal government has been warning people about the dangers of smoking for decades. In 1964 the first Surgeon General's Report on Smoking and Health was issued. Tobacco use, which had skyrocketed since 1900, dropped dramatically.

The latest smoking statistics by the CDC were published in Health, United States, 2003. In 2001 approximately 46.2 million American adults smoked cigarettes, representing 22.7 percent of the adult population (18 years of age and older). (See Table 8.4.) This percentage has declined significantly since 1965 when 41.9 percent of the adult population smoked. In 2001 slightly more adult males (24.7 percent) than females (20.8 percent) were smokers. African-American males aged 45-64 years (34.3 percent) and white males aged 18–24 years (32.5 percent) were most likely to smoke. Approximately one-third of both groups were current smokers in 2001. Education level and smoking are inversely related in adults; people with limited education are much more likely to smoke than are those with advanced degrees.

Table 8.5 shows the prevalence of smoking among high school seniors and eighth- and tenth-graders for various years between 1980 and 2002. In 2002 more than one quarter of high school seniors were smokers, as were nearly 18 percent of tenth-graders and nearly 11 percent of eighth-graders. These values have all declined in recent years.

In April 2002 the CDC issued its latest report on mortality associated with cigarette smoking. Based on data for 1995–99, the report states that smoking kills more than 440,000 people annually. Smoking is blamed for the deaths of 264,087 men and 178,311 women each year from 1995 to 1999. Smoking resulted in the average loss of 13.2 years of life for men and 14.5 years of life for women. Smoking during pregnancy is blamed for 1,000 infant deaths annually. The CDC noted that each pack of cigarettes sold in the United States costs the country $7.18 in medical care costs.

The CDC summarized its findings on the link between cigarette smoking and disease in the 2003 publication of "Cigarette Smoking—Attributable Morbidity—United States, 2000." The report estimates that 8.6 million people in the United States suffered from serious illnesses in 2000 due to smoking. Chronic bronchitis and emphysema accounted for 59 percent of all smoking-attributable diseases. The data are presented in Table 8.6.

In addition to nicotine, which is very addictive, cigarette smoke contains hundreds of mutagens, carcinogens,

and some 4,000 other chemical compounds including carbon monoxide and radioactive polonium. These chemicals not only enter the lungs, but also the bloodstream where they circulate into internal organs. Smoking can be responsible for, or contribute to, asthma; heart disease; cancer of the lungs, esophagus, mouth, bladder, pancreas,

and pharynx; bronchitis; emphysema; and low birth weight babies. One ironic result of the attempt to reduce smoking has been the marked increase in the use of smokeless tobacco, which can cause oral cancers. Tobacco use is known to increase the risks for nine cancers. According to the U.S. National Cancer Institute, it is the leading cause of 30 percent of all cancer deaths and 87 percent of lung cancer deaths.

Environmental Tobacco Smoke

While the dangers of smoking to smokers have been known for quite some time, the risks to nonsmokers have only recently attracted attention. In May 2000 the NIH released its ninth Report on Carcinogens in which substances, such as metals, pesticides, and other chemicals, are identified as "known" or "reasonably anticipated" to cause cancer and to which a significant number of Americans are exposed. For the first time the report included environmental tobacco (secondhand) smoke (ETS) as a "known" human carcinogen.

ETS is classified by the EPA as a Group A carcinogen, because it is known to cause cancer in humans. According to the CDC, exposure to ETS causes 3,000 lung cancer deaths annually among nonsmokers and increases the risk for heart disease. As many as 62,000 deaths every year from coronary heart disease are estimated as attributable to ETS. Secondhand smoke is also blamed for aggravating respiratory problems and ear infections in children and increasing the risk of sudden infant death syndrome. Passive smokers (those who inhale the smoke from others' cigarettes) have a 30 percent greater risk of dying of lung cancer than those who are not passive smokers.

ETS contains cotinine, a chemical that results from the breakdown of nicotine in the body. Cotinine levels in urine, saliva, hair, and blood can be measured. Active smokers have cotinine levels in excess of 15 nanograms per milliliter (ng/mL). Nonsmokers with average exposure to ETS have cotinine levels less than 1 ng/mL. The CDC reports that nearly 90 percent of the U.S. population had measurable levels of serum cotinine in their blood in 1991. Among nonsmokers the median cotinine level was 0.20 ng/mL. By 1999 this value had dropped to less than 0.050 ng/mL, a 75 percent decrease. Figure 8.11 shows that the concentration of cotinine measured in children's blood declined by more than 50 percent between 1988 and 2000.

Until the late 1990s nonsmokers generally had no choice about breathing tobacco smoke in many public buildings, including hospitals. This is no longer the case and, in fact, smokers may find themselves ostracized or, at the very least, required to smoke in designated areas. Many American companies are banning smoking from the workplace; some even refuse to hire smokers. Also, some restaurants and social clubs—places where smoking has historically been common—have begun to ban, or severely curtail, smoking on their premises.

Tobacco and the Legal System

In June 2002 a 67-year-old man from Kansas was awarded $15 million in punitive damages from R. J.

Reynolds (RJR) tobacco company. The man, who smoked for more than 40 years, had lost both legs to a circulatory disease that he blamed on smoking. It was the first time that a federal judge awarded punitive damages against a tobacco company. The judge ruled that the company had concealed the addictiveness of cigarettes. In the same week a man who had lost his tongue to cancer was awarded $37.5 million from Philip Morris, Brown and Williamson, and the Liggett Group by a Miami jury.

When individuals sue tobacco companies, they claim that cigarette smoking contributed to their ill health in a variety of ways. Some of the issues raised in these suits include the following:

• The cost to society for medical expenses related to tobacco use
• Advertising and selling tobacco products to youth
• The location and placement of tobacco products
• Taxes on tobacco products
• The harmful effects of secondhand smoke
• The addictive nature of nicotine
• The failure of tobacco companies to divulge information about the harmful and addictive nature of smoking, and their concealment of evidence to that fact
• Smoking in public buildings

Tobacco companies argue that smokers choose to smoke and that they must assume the risk for doing so. In the landmark 1994 case Cipollone v. Liggett Group Inc.(60 LW 4703), the Supreme Court ruled that smokers may sue cigarette companies for concealing facts about smoking and that the Liggett Group was at least partially liable in the death of Rose Cipollone. However, the court also determined that Cipollone herself was partially responsible for her cigarette use and subsequent death.

In 1991 the AMA publicly charged RJR with targeting children through its Joe Camel advertising campaign. Later that year Janet Mangini, a California attorney, brought suit to end the Joe Camel campaign, becoming the first person to legally challenge the tobacco industry for targeting minors in its advertising. Six years of "discovery," that is, taking depositions and obtaining records, followed. As the trial date neared in May 1997, RJR offered to halt the ad campaign in order to stop the trial and also agreed to provide for public release of its documents about youth marketing and the Joe Camel campaign.

In the 1997 case Broin v. Philip Morris, a flight attendant sued claiming that secondhand smoke in airplanes had harmed her health. The suit was settled out of court with Philip Morris agreeing to pay some $300 million to establish a medical foundation.

Nevertheless most legal action against "Big Tobacco" prior to 1998 was unsuccessful because most of the suits were filed as class action suits, where large numbers of complainants unite to sue. The 1995 case Castono v. The American Tobacco Company Inc. (85 F 3rd 734, 5th Cir. 1996), filed in Louisiana, included people who had purchased and smoked cigarettes and had become nicotine dependent. The U.S. District Appeals Court in Louisiana "decertified" the suit, ruling that individual issues predominated over common issues, thus making the case not a proper candidate for a class action.

That ruling—that individual issues were greater than common issues in suits against the tobacco industry—has been handed down both by state and federal courts in at least 30 suits. In 1996, however, in Howard A. Engle, MD v. R. J. Reynolds Tobacco, Philip Morris, Brown and Williams, Lorillard Tobacco, the American Tobacco Company, et al., filed in Dade County, Florida, the state appellate court ruled that the suit could proceed to trial, although it was reduced to include only Florida residents. In 1999 the jury ruled for the plaintiffs and, in July 2000, assessed penalties of $145 billion in punitive damages against the country's five largest tobacco companies. The money was to be split among Florida residents who could prove they became ill from smoking. Philip Morris was ordered to pay $73.96 billion, RJR $36.28 billion, Brown and Williamson $17.59 billion, Lorillard Tobacco $16.25 billion, and the Liggett Group $790 million.

The trial, which lasted for two years, was the longest civil trial in the history of tobacco litigation, and the penalty was the largest ever levied in any case. Rather than building their case around the dangers of smoking, the plaintiffs focused on the negligent conduct of the tobacco companies that they claimed had covered up smoking risks for more than four decades. While some observers suggested that the jury's decision would encourage other class actions, tobacco industry executives contend that the ruling will be reversed on appeal. They claim that the case will be overturned because it should not have been allowed as a class action and that the fine is outrageous and will put the tobacco companies out of business. In any case, legal experts predicted the verdict was many years away from being final.

In the mid-1990s a number of state governments initiated suits against tobacco companies to recoup state Medicaid spending on tobacco-related illnesses. With the pressure of state and private lawsuits building up, the tobacco industry has begun to seek settlements with the states. In November 1998, in what was termed a "Master Settlement Agreement" between the major tobacco manufacturers and 46 state attorneys general (Texas, Florida, Minnesota, and Mississippi settled independently), the tobacco companies agreed to accept a number of limitations on how they marketed and sold their products. These included: ceasing youth-targeted advertising, marketing, and promotion by stopping the use of cartoon characters in advertising; limiting brand-name sponsorship of events with significant youth audiences; terminating outdoor advertising; banning youth access to free samples; and setting the minimum cigarette package size at 20. In addition to these limits on their business practices, the tobacco industry agreed to pay more than $200 billion to the states.

In the 1990s testimony before Congress claimed that the tobacco industry deliberately manipulated the amount of nicotine in its cigarettes, and that cigarettes were nothing more than a delivery system for nicotine, a drug now widely recognized as physiologically addictive. The industry feared that if cigarettes were perceived as a delivery system for nicotine, tobacco products might fall under the control of the FDA. In 1995 the FDA ruled that nicotine was indeed a drug and liable to its regulation—the first time the tobacco industry had been regulated. In March 2000, however, the Supreme Court ruled 5–4 that the FDA does not have jurisdiction to regulate tobacco products or cigarette-company marketing practices under existing law.

In his 1999 State of the Union address, President Bill Clinton announced his intent to sue the tobacco industry to recover money spent by the federal government to treat illnesses caused by smoking. Accordingly, the U.S. Department of Justice filed suit in September 1999 (United States of America v. Philip Morris Inc., et al.) in the U.S. District Court for the District of Columbia. The government accused the tobacco companies of misleading and defrauding the public about the dangers of smoking. In September 2000 a federal judge dismissed part of the lawsuit in which the government was seeking to recover billions of dollars spent in health care costs related to smoking. As of April 2004 the government is seeking $289 billion in its case against the tobacco companies. The case is expected to go to trial in late 2004. It will likely be the most complex and lengthy case ever tried in U.S. court. Government attorneys plan to submit more than one million pages of exhibits as evidence.

INDOOR AIR TOXINS

Indoor pollution has become a serious problem in America. Although most people think of outdoor air when they think of air pollution, studies now reveal that indoor environments are not safe havens from air pollution. As discussed earlier, lead, asbestos, radon, and ETS all pose serious and costly problems in indoor settings. Modern indoor environments contain a variety of pollution sources, including synthetic building materials, consumer products, and dust mites (minute insects that live on house dust and human skin residue). People, pets, and indoor plants also contribute to airborne pollution. Improvements in home and building insulation and the widespread use of central air conditioning and heating systems have largely ensured that any contaminant present indoors will not be diluted by outside air and, therefore, will become more concentrated.

Indoor pollution, however, is not just a product of modern, well-insulated homes and buildings. In 1995 doctors in the Bronx, New York, began observing an emerging epidemic of asthma, citing hospitalization rates as high as 17.3 per 1,000 people and death rates as high as 11 per 100,000. Both rates were eight times the national average and the rate of incidence among children was twice the national rate. The Bronx, an area with many dilapidated and neglected buildings, is among the worst places in the country for asthma. Among the causes cited by area physicians were many factors associated with indoor pollution: dust mites, cockroaches, smoking, dust, and respiratory viruses and bacteria (which spread easily in crowded quarters). Scientists suspected that stress and the start-up of a waste incinerator in the Bronx three years earlier were factors as well.

The EPA and other sources identify indoor pollution as one of the most serious environmental risks to human health because:

• concentrations of pollutants in indoor air can be more than two to five times higher than those in outdoor air;
• people spend an average of 80 to 90 percent of their time indoors, even more for certain groups, such as the elderly, the chronically ill, and the very young; and
• the indoor environment is unique in that it contains materials and surfaces that act as emitters and reservoirs of pollutants.

Reports of illness and allergy among building occupants have become commonplace. Scientific evidence suggests that respiratory diseases, allergies, mucous membrane irritation, nervous system defects, cardiovascular symptoms, reproductive problems, and lung cancer may be linked to exposure to indoor air pollution.

Poorly ventilated buildings sometimes become the cause of "sick-building syndrome." The term, first employed in the 1970s, describes a spectrum of specific and nonspecific complaints reported by building occupants. Such symptoms might include headaches, fatigue, or difficulty breathing, which begin soon after entering a building and subside after leaving that building. When 20 percent of a building's occupants report complaints, the World Health Organization (WHO) calls that building "sick." Experts generally believe there are many people who do not complain, even when they experience symptoms, and the WHO and the EPA estimate that 30 percent of all buildings worldwide are unfit for human occupation. Surveys and assessments by private corporations and federal agencies estimate that sick-building syndrome goes undetected in another 10 to 15 percent of structures. Many billions of dollars in income and productivity are lost annually because of employees falling ill from problems linked to sick-building syndrome.

The first legislation to deal specifically with indoor air quality was Title IV of the Superfund Amendments and Reauthorization Act of 1986, which called for the EPA to establish an advisory committee to conduct research and disseminate information. In October 1991 the GAO reported on the progress of the legislation in Indoor Air Pollution: Federal Efforts Are Not Effectively Addressing a Growing Problem. The GAO concluded not only that the EPA's emphasis on indoor pollution was not commensurate with the health risks posed by the problem, but also that research had been, and would likely continue to be, constrained by a lack of funding. Accordingly, the proposed Indoor Air Quality Act of 1991 was not enacted by Congress.

Federal agencies reported that they spent a total of almost $1.1 billion on indoor pollution-related research from 1987 to 1999. Most of that amount went toward indoor air research, followed by studies of lead, asbestos, and radon. The NIEHS spent the most (almost $400 million), with the National Heart, Lung, and Blood Institute spending $175.2 million, the EPA $140.4 million, the DOE $136.5 million, and the National Institute of Allergy and Infectious Diseases $93.7 million.

In 1999 the GAO once again reviewed the status of indoor air quality activities. In Indoor Pollution: Status of Federal Research Activities, the GAO found that significant strides have been made in understanding the risks posed by chemicals and other contaminants commonly found in homes, offices, and schools. Nonetheless it concluded that "many gaps and uncertainties remain in the assessment of exposures to known indoor pollutants." These gaps include specific sources of exposures; the magnitude of exposures; the relative role of specific exposures such as inhalation, ingestion, and skin contact; the nature, duration, and frequency of human activities that contribute to exposures; and the geographic distribution of exposures to certain pollutants for the U.S. population as a whole.

NOISE POLLUTION

Noise is unwanted sound. The word is derived from the Latin word nausea, meaning seasickness. Experts agree that noise pollution is bad and getting worse in America. Noise from road traffic, airplanes, jet skis, garbage trucks, construction equipment, manufacturing processes, lawn mowers, subways, and leaf blowers are just a few of the unwanted sounds that are routinely broadcast into the air. Physicists, audiologists, engineers, architects, and physicians report that permanent hearing loss caused by amplified music is a widespread affliction in the United States. Although hearing loss is the most dramatic effect of noise pollution, even smaller amounts of noise can negatively affect health and well-being. Besides hearing loss, some other problems related to noise include the following:

• stress
• high blood pressure
• sleep loss
• distraction and lost worker productivity
• a general decline in quality of life

Noise levels are measured in decibels (db). A noise level of less than 65 db is considered acceptable from an environmental standpoint, although several studies have found that levels of 60 to 65 db are annoying to 9 percent of the public. Soft whispers have a decibel level of 30. An air conditioner at 20 feet measures 60 db. The noise level of a vacuum cleaner or a crowded restaurant is about 70 db. Average city traffic, garbage disposals, or alarm clocks at 2 feet could be 80 db. The subway, a motorcycle, or a lawn mower would be approximately 90 db; a basketball arena 108 db. A rock concert or thunderclap (120 db), a gunshot blast or jet plane (140 db), or a rocket launching pad (180 db) can be dangerous to those under constant exposure. Researchers for the EPA have found that 20 percent of the population is "highly annoyed" if sound levels reach 55 db.

Many cities have pressed the Federal Aviation Administration to steer airplane flight paths around metropolitan areas in order to reduce noise over residential areas. The airline industry has responded by beginning to build jet engines with noise levels in mind.

Legislation against Noise

The air into which noise is emitted is a "commons," or a public space. It belongs to no one person but to everyone. People, organizations, and businesses, therefore, do not have unlimited rights to broadcast noise. The United States has been slow to confront the issue of noise. At a time when European nations were addressing the issue of noise abatement, in 1981 Congress eliminated the EPA's previously allocated funds for noise programs.

The Office of Noise Abatement and Control (ONAC) of the EPA was established by the Noise Control Act of 1972 (NCA; PL 92-574). During President Ronald Reagan's administration, noise pollution came to be viewed as a local problem because noise pollution does not travel very far and quickly dissipates. Some legislators believed that state and local regulation was more efficient than federal regulation since local governments could more easily gauge and respond to noise situations in their area. Consequently, in 1981 Congress eliminated all funding for ONAC, although it did not repeal the NCA. And while many of the provisions of that original law have become outdated and obsolete, others still—technically—could be invoked, although they generally have not been.

Thus, noise pollution has fallen to state and local governments to define and regulate. Much like the federal government, most states have been slow to do so. Increasingly, however, citizens are filing lawsuits based on noise issues. People regularly file noise complaints against airports and road builders, and police often respond to noise-related neighborhood conflicts.

TOXINS IN FOOD

Chemicals and Pesticides

Noncommercially caught fish and wildlife are sometimes contaminated with chemicals, such as mercury, PCBs, and DDT. In order to protect consumers from health risks associated with consuming such pollutants, the EPA and the states issue consumption advisories to inform the public that high concentrations of contaminants have been found in local specimens. According to the EPA in Update: National Listing of Fish and Wildlife Advisories (May 2003), in 2002 (the latest year for which data are available), 2,800 advisories were in effect.

The total number of lake areas and river miles under advisory for various pollutants between 1993 and 2003 is shown in Figure 8.12 and Figure 8.13. All five of the specific contaminants listed are bioaccumulative, meaning that they accumulate in the tissues of aquatic organisms at much higher concentrations than are found in the water. These contaminants also persist in the environment for a relatively long time.

The GAO report Information on EPA's Draft Reassessment of Dioxins (April 2002) provided the EPA's estimates of the average U.S. adult's exposure to dioxins in food on a daily basis. (See Table 8.7.) Beef and freshwater fish and shellfish are the major sources of exposure. These levels are associated with adverse health effects, but are below the levels associated with cancer. Levels of exposure are thought to be even greater in people who have diets high in fat content.

Pathogens

According to federal officials, the U.S. food supply is among the safest in the world. Nevertheless, episodes of food poisoning and diseases occur in the United States. Based on "Food-Related Illness and Death in the United States" by Paul S. Mead et al. (Emerging Infectious Diseases, vol. 5, no. 5, 1999), the CDC estimates that as many as 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths annually are caused by foodborne hazards. Unfortunately, most of the incidences cannot be traced to a particular pathogen, but are attributed to "unknown" agents. Known pathogens are associated with 14 million illnesses, 60,000 hospitalizations, and 1,800 deaths annually. Three pathogens, Salmonella, Listeria, and Toxoplasma, are blamed for more than 75 percent of the deaths.

Foodborne illnesses became the object of intense public scrutiny following an outbreak of Escherichiacoli (E.coli) in 1993 that killed four people and sickened hundreds. The illness was attributed to undercooked hamburgers from fast-food restaurants. The FDA responded by raising the recommended internal temperature for cooked hamburgers to 155 degrees Fahrenheit. A sampling program was begun to test for E. coli in raw ground beef. New labels containing food handling instructions were required on consumer packages of raw meats and poultry.

In 1996 more illnesses were attributed to E. coli, this time in unpasteurized apple juice. The FDA proposed new regulations to improve the safety of fresh and processed juices. In that same year several federal and state agencies established a surveillance program called FoodNet to monitor laboratory-identified foodborne diseases related to seven pathogens in parts of five states. By 2002 the program had grown to monitor 12 pathogens and syndromes in nine states, encompassing 37.4 million people (13 percent of the U.S. population). FoodNet data for 2002 are presented in Table 8.8.

FoodNet identified 16,580 cases of foodborne illnesses related to monitored pathogens in 2002. Salmonella accounted for 36 percent of cases, followed by Campylobacter (30 percent), and Shigella (23 percent).

The incidence of diseases attributed to Listeria, Yersinia, and Campylobacter decreased dramatically between 1996 and 2002. The CDC attributes the decline to several factors including increased public awareness about foodborne diseases and food safety, new pathogen reduction measures implemented by the U.S. Department of Agriculture (USDA) at meat and poultry slaughterhouses and processing plants, egg quality assurance programs, better agricultural practices that ensure produce safety, increased regulation of imported foods and fruit and vegetable juices, and the introduction of hazard reduction measures in the seafood industry.

Eating Habits and Food Preparation

Americans have changed their eating habits, and with such changes have come additional risks. Some explanations for the high rate of foodborne illnesses include the following:

• Americans are eating out more than in the past.
• More and more foods are being imported from foreign countries.
• New pathogens and strains of organisms are turning up in the food supply.
• Many people are careless about food preparation in the home.

In 1997 the CDC found that, among the factors that contributed to the transmission of foodborne disease, improper handling temperatures caused the most cases, followed by poor personal hygiene of handlers, contaminated equipment, inadequate cooking, and food from unsafe sources.

Contamination from Produce

The per capita consumption of fresh produce has increased in the United States in recent years. Some Americans may be eating more produce for health reasons and, because of growing commerce between nations all over the globe, a wider variety of fruits and vegetables are available today.

Researchers Larry R. Beuchat and Jee-Hoon Ryu conducted a study for the CDC of factors associated with produce contamination. As reported in "Produce Handling and Processing Practices" (Emerging Infectious Diseases, vol. 3, no. 4, 1997), they determined that contamination of produce can occur in the field or orchard, during harvesting or processing, in transport or marketing, or in the home or restaurant. The scientists categorized sources of contamination as preharvest or postharvest.

Preharvest sources include feces in soil or fertilizer, organisms in the soil, pollution of water used to irrigate or spray crops, dust and air, animals (including birds), insects, and human handling. Postharvest factors include feces, handling by workers or consumers, farm equipment, transport containers, insects, and animals. Other possible postharvest sources are air and dust, wash water, processing equipment, ice, transport vehicles, improper storage or packaging, inappropriate temperatures, cross-contamination from other foods, and incorrect handling. Beuchat and Ryu concluded: "Control or elimination of pathogenic microorganisms from fresh fruit and vegetables can be achieved only by addressing the entire system—from the field, orchard, or vineyard to the point of consumption."

Organic Foods—A Booming Industry

Some consumers are concerned about certain technologies being applied to the food supply, including irradiation, the use of hormones in milk production, and genetically engineered crops. Irradiation, in particular, is a highly controversial subject. About 40 countries worldwide use irradiation, in which food is briefly exposed to radiant energy, such as gamma rays or high-energy electrons, as a means of controlling pathogens. Some foods in the United States have been irradiated since the 1960s. (See Table 8.9.) A 2000 report on food irradiation by the GAO reported that 95 million pounds of food products were irradiated in 1999, representing about 10 percent of their total consumption. The GAO concluded that the benefits of irradiation in terms of reduced mortality, illnesses, and associated costs outweighed the minimal risks. Risks commonly attributed to food irradiation include possible creation of chemical byproducts and loss of nutritional value.

The USDA defines organic agriculture as an "ecological production management system that promotes and enhances biodiversity, biological cycles, and soil biological activity. It is based on minimal use of off-farm inputs and on management practices that restore, maintain, and enhance ecological harmony." Organic agriculture is both an approach to food production based on biological methods that avoid the use of synthetic crops or livestock products, and a broadly defined philosophical approach to farming that puts value on ecology, conservation, and nonintensive animal breeding practices. Some conventional practices not accepted in organic agriculture include the following:

• Synthetic fertilizer and pesticides
• Confinement livestock operations such as feed lots or cages where animals are fattened before slaughter
• Routine use of growth-enhancing animal drugs such as hormones or antibiotics
• Genetically modified crops
• Irradiation of foods for preservation or decontamination

While organic methods of farming emerged in the United States and Europe in the early 1900s, it was not until the late 1980s that research groups and consumers began to express widespread interest in such practices. Beginning in 1989 sales of organically produced products began to climb, growing, on average, 20 percent per year. According to the 2003 USDA report U.S. Organic Farming in 2000-2001: Adoption of Certified Systems by Catherine Greene and Amy Kremen, in 2001 sales of organic products reached approximately $9 billion in the United States and $21 billion worldwide. Organic food sales accounted for 1–2 percent of total food sales in all major world markets.

In the same report the USDA notes that there were nearly 7,000 certified organic operations in the United

States in 2001, up from 5,000 operations in 1997. The acres of farmland managed under certified systems increased by 74 percent during those years, from 1.4 million acres in 1997 to 2.2 million acres in 2001.

For most of its history the organic food industry established its own organizations and standards, with approximately 33 private certification operations. However, there was no consistency in labeling and no guarantee that foods labeled as organic are actually grown and processed in a purely organic fashion.

In 1990 Congress passed the Organic Foods Production Act (Title 21 of PL 10-624) to regulate the organic food industry. The act authorized the National Organic Program (NOP) to be administered by the USDA. The program would define standard practices and certify that operations meet those standards. It would be illegal for anyone to use the word "organic" on a product if it does not meet the defined criteria.

CHEMICAL AND BIOLOGICAL WEAPONS

More and more the world faces threats from toxins intentionally and maliciously introduced into the environment with the sole purpose of harming people. The anthrax letters that followed the terrorist attacks of September 11, 2001, have brought new focus to the dangers of toxins that can be used for chemical and biological weapons. While some of these toxins can be identified, such as anthrax, others remain of mysterious origin, making it much more difficult to treat those who are affected.

Anthrax

Anthrax is a disease caused by the spore-forming bacterium Bacillus anthracis. Anthrax is found in nature mostly in agricultural areas, where it is associated with livestock, such as cattle, sheep, and goats. The spores can survive in soils for many years. Human exposure to anthrax is usually through infected animals or animal products, such as meat, hides, wool, or leather. Anthrax can enter the body either through inhalation, via the skin (cutaneous), or ingestion. Inhaled anthrax is the most lethal. Anthrax is not contagious and is treatable by antibiotics if detected early enough in the disease.

Between 1955 and 1999 there were only 236 reported cases of anthrax in the United States, most of them cutaneous. An inhalation case of anthrax had not occurred since 1976, when a man working with infected imported yarns died of the disease. In October and November 2001 there were ten confirmed cases of inhalation anthrax in Florida, New York, New Jersey, and the District of Columbia. All resulted from intentional release of the spores through mailed letters or packages. Five of those infected died.

Gulf War Syndrome

Many veterans of the 1991 Persian Gulf War returned with physical complaints that have baffled medical experts. "Gulf War syndrome" is the name given to an array of symptoms—fatigue, skin rashes, memory loss, and headaches—experienced by men and women who served in the war. Some sources have claimed these conditions may have resulted from exposure to poison gas that was inadvertently released when American troops destroyed caches of the gas following the actual conflict, others contend the troops were heavily exposed to fumes of burning oil during the war, while still others suggest that the immunizations given to the soldiers may have caused such responses.

The Department of Veterans Affairs (VA) offers Gulf War veterans eligibility for medical treatment. More than 67,000 service members have responded to the VA's Gulf War Registry program, which offers physical examinations to all eligible service members. Most veterans are diagnosed and treated; for some, however, symptoms have been chronic. Data from about 10,000 claimants' health exams found unexplained illness in approximately 12 percent of the cases. If a veteran's symptoms defy diagnosis, the veteran can be referred to one of the nation's four Gulf War Referral Centers for treatment.

In 1995 the federal government began devoting $115 million for 121 research projects related to Gulf War illnesses. The VA has provided compensation payments to chronically disabled Gulf War veterans with undiagnosed illnesses. (A disability is considered chronic if it lasts more than six months.)

The federal response to the health consequences of Gulf War service is led by the Persian Gulf Veterans Coordinating Board, composed of the VA and the U.S. Departments of Defense and Health and Human Services. The Presidential Advisory Committee on Gulf War Veterans' Illnesses was formed by President Bill Clinton in 1995. In 1999 he signed into law the Veterans Millennium Health Care and Benefits Act (PL 106-117), which extended medical care to veterans, their spouses, and their children until December 31, 2003.