The Automobile and the Environment in American History

by Martin V. Melosi

Auto Emissions and Air Pollution

The Santa Barbara oil spill was a dramatic reminder of the risks inherent in the search for energy resources. Emissions from the internal combustion engine, however, have proved to be the most significant environmental consequence of oil production. Street cleaners who sang the praises of the motor car for delivering them from tons of horse manure could not appreciate that the environmental panacea of one generation proved to be the bane of another. The technical limits of the internal combustion engine and the scale of automobile use produced devastating forms of pollution.

Some pollution crises in the postwar years were harbingers of things to come. In 1948, a temperature inversion kept a dense smoke cloud of sulfur dioxide and particulate matter close to the ground for six days in the steel mill town of Donora, Pennsylvania. On the fifth day, October 30, seventeen people died, followed by two more deaths twenty-four hours later. Almost 43 percent of the townspeople became ill, with more than 10 percent (1,440) "severely affected." The tragedy at Donora made postwar Americans aware of the health hazards of air pollution. Those dangers were reconfirmed by the "killer smog" that hit London in 1952 (4,000 deaths) and the serious smog attack in New York City in 1953 (200 deaths). Congress enacted the National Air Pollution Control Act in 1955 to generate research on air pollution, but how automobile emissions fit into the story took several years to evaluate and even longer to address.

A relatively new source of air contamination, automobile emissions posed different problems than manufacturing discharges such as coal smoke. Before the Industrial Revolution, levels of toxic chemicals in the air were relatively low, but increased fossil-fuel production and use dramatically decreased air quality. The addition of many thousands of cars on the road in the years after World War II intensified the spread of air pollution, added more and newer sources of pollutants, and most immediately threatened many major cities.

In the 1940s, citizens of the car-dominated Los Angeles basin complained about a white or sometimes yellow-brown haze that made their eyes tear. They referred to this irritation as "smog." The word was taken from a combination of "smoke" and "fog," a term purportedly coined in 1905 by Dr. H.A. Des Voeux of London ’s Coal Smoke Abatement Society. The more recent version of smog, primarily from automobile emissions, is composed of a complex of carbon monoxide, hydrocarbons, sulfur oxides, nitrogen oxides, waste heat, and aerosols (liquid droplets, solid particles, and other various mixtures of liquids and solids suspended in air). Tropospheric ozone, located a few feet above ground, is another significant component of smog. In the late 1980s, at least 60 million people in North America regularly breathed air that failed to achieve federal air quality standards established ten years earlier; during the summer heat wave in 1988, the number rose to 120 million. Ozone is clearly one of the worst offenders, especially in cities such as Houston, Los Angeles, Baltimore, New York, Philadelphia, Washington, D.C., and Toronto.

Individually or together, the various components pose a health hazard to humans. Auto emissions can cause headaches, contribute to lung cancer, emphysema, and various other respiratory and cardiovascular problems, and have been linked to low birth weight in infants. They also modify weather conditions, damage vegetation, and eat away at rubber, textiles, dyes, and other materials.

The use of tetraethyl lead as a gasoline additive in 1923 introduced yet another toxic substance to automobile emissions that threatened human health. Concerns among public health officials about the poisonous nature of the substance did not deter General Motors and others from promoting leaded gasoline. As environmental historian Ted Steinberg noted, “With the burning of huge quantities of gasoline (especially in the three decades after 1950), lead was deposited on the soil and, unknowingly, tracked into houses across the nation. Infants crawling on the floor then picked it up on their fingers and ingested it, interfering with the development of their nervous systems and contributing to hyperactivity and hearing loss, among other effects, although it would be decades . . . before the full scope of the problem became evident.” Unfortunately, lead does not break down once released into the air, and between the 1920s and 1986—when it finally was being phased out as a gasoline additive—seven million tons of lead was spewed out by cars across the country.

While air pollution from cars was a growing problem throughout the immediate postwar period, it was not an issue among automobile manufacturers, oil companies, or the public. Los Angeles, the "smog capital of America," was probably the first city to raise major public concern over auto emissions, and became the living laboratory for studying the causes and effects of massive doses of smog. The State of California also was the first state to establish new-car emission standards.

As early as 1959, eye irritation was reported in Los Angeles County on 187 days; in 1962, 212 days. A typical car produced in 1963 (without pollution control devices) discharged 520 pounds of hydrocarbons, 1,700 pounds of carbon monoxide, and 90 pounds of nitrogen oxide for every 10,000 miles traveled. In 1966, 86 million of approximately 146 million tons of pollutants discharged into the air in the United States was attributable to motor vehicle traffic.

Beginning in 1947 Los Angeles had reduced sulfur dioxide emissions by banning the use of coal and fuel oils for industrial purposes, but the smog problem continued to increase. In the 1950s suspicions were being raised about the contribution of motor vehicles to the air pollution problem of the area. Dr. A.J. Haagen-Smit and other scientists conducting pioneering chemistry research at the California Institute of Technology discovered that nitrogen oxides and hydrocarbons exposed to sunlight produced secondary pollutants (photochemical smog or PCS) that caused eye and throat irritations and reduced visibility in the Los Angeles area. Further studies indicated that the complex and various pollutants existing in automobile emissions came from four sources: engine exhaust, crankcase blowby (through the engine ventilation system), the carburetor, and the fuel tank. These investigations were central to the development of various emissions-control technologies.

Multiplied by thousands of cars, the smog problem in Los Angeles was critical. California became the logical testing ground for several emissions-control devices and some pioneering legislation. Initially, neither the automobile industry nor the petroleum industry was a willing participant in addressing the problem. For its part, the auto industry was not interested in committing time or money to redesigning its cars, and only reluctantly and largely because of new legislation was forced to retrofit cars with emission-control devices. (Interestingly, little serious consideration was given to encouraging or requiring motorists to alter their driving habits.)

As early as 1953, Los Angeles County Supervisor Kenneth Hahn inquired of Detroit automobile makers as to whether research was being conducted to eliminate emissions. The response was vague. With the threat of mandatory federal regulations, the auto industry began to install crankcase blowby devices (which returned unburned gases to the combustion chambers) on their cars. This was a significant advance because crankcase blowby produced 25 percent of the engine's hydrocarbon emissions. This equipment became mandatory on all cars sold in California beginning with the 1963 models.

This was only a start, since no effort was made to control exhaust emissions that were responsible for 55 percent of the hydrocarbons, most of the waste heat, and all of the carbon monoxide, nitrogen oxides, and lead emissions. Once again the industry balked, but in 1966 California required exhaust-control devices on all new cars. However, the 12 percent drop in hydrocarbon emissions and reduction in carbon monoxide experienced in Los Angeles between 1965 and 1968 was accompanied by a 28 percent rise in nitrogen oxides. By 1968, nitrogen dioxide, which is highly poisonous, exceeded the "adverse" level on 132 days. The serious increases in nitrogen oxides were due to the inability of available antiemissions technology to act on them, as well as to the increase in automobiles and rising gasoline consumption. A new technical fix was sought from the automobile industry and, in response, catalytic exhaust devices were developed to convert nitrogen oxides into harmless by-products. Catalytic converters were required on all 1975 cars sold in California. Leaded gasoline, however, played havoc with the catalysts. One solution was to use lead-free or unleaded gasoline. (Another was the unauthorized removal of the devices by motorists.) While non-leaded gas became available, the complete phase-out of leaded gasoline, as stated earlier, did not commence until 1986.

Outside of California, the states moved slowly to combat automobile emissions. By 1966, motor vehicles contributed more than 60 percent of the pollutants in the atmosphere throughout the nation. Temperature inversions in at least 27 states and the District of Columbia produced serious smog problems. The more widespread use of trucks and airplanes exacerbated the nation's air pollution problems.

It became apparent during the 1960s that smog was not a local problem, but a national one requiring the attention of the federal government. While California still led the way in emissions-control legislation, federal laws moved toward recognition of the problem. The 1963 Clean Air Act for the first time gave the federal government limited enforcement power over interstate pollution. The Motor Vehicle Air Pollution Act of 1965 produced national standards comparable to California law for the 1968 model year. Also in 1967, the Air Quality Act was the first piece of federal legislation designed to control lead emissions. Federal funds became available to defray part of the cost of inspection programs. Hydrocarbon emissions came under federal jurisdiction in 1968.

The meteoric rise in environmental concern, the dissatisfaction with existing federal laws, and the lackluster accomplishments of the states provided the momentum for the 1970 Clean Air Amendments. Dealing with both auto emissions and stationary sources of pollution, the new legislation was the most stringent air pollution law ever passed in the United States. An amendment to the 1970 Clean Air Act called for further reductions in emissions and authorized the Environmental Protection Agency (EPA) to set emissions standards for new automobiles and other motor vehicles concerning pollutants that would adversely affect human health.

Intentions, however, were not always equal to actions. Implementation of the Clean Air Amendments was made difficult by a reluctant automobile industry and the energy crisis of the early 1970s. The 1970 act gave the auto industry a temporary way out of meeting the tougher standards. Under the provisions of the act, the EPA administrator could grant a one-year delay if the companies made "good faith" efforts to meet the new standards. Some critics questioned whether the manufacturers had, in fact, made such a gesture, since they relied on the research and development work of independent companies for emissions-control technology rather than utilizing their own resources.

EPA Administrator William Ruckelshaus denied the delay on the grounds that the companies were capable of meeting the 1975 deadline. Four auto companies then sued the EPA for refusing to extend the deadline, and, in 1973, the Court of Appeals ruled in favor of the plaintiffs. The onset of the energy crisis prompted Congress to extend the deadline further, and apprehension about the safety of the catalytic converters again pushed back the deadline. In 1977, a three-year suspension was granted.

While emissions standards attempted to address one environmental problem associated with motor vehicles, it actually helped produce another. During the period frpm 1968 to 1974, with the primary emphasis of regulation on emissions control, fuel economy of motor vehicles suffered, thus increasing demand for gasoline. One way of enhancing fuel economy was reducing the weight of vehicles, and data for 1977-1980 indicates that fuel economy improved almost in direct proportion to reduced vehicle weight. (Of course, concerns about the safety of vehicles arose as some cars on the road became lighter, while older models retained their bulk.) The introduction of the oxidation catalytic converter in 1975 also helped to improve fuel economy as well as reduce emissions. Electronic engine control later added another layer of technology.

The energy crisis of the 1970s produced a mixed record with respect to auto emissions. The American automobile industry, especially Chrysler, was woefully unprepared to meet the challenge of fuel economy demanded by the rise in gasoline prices. Americans turned to small Japanese and European cars, while Detroit plunged into a deep depression. Alternatives to the internal combustion engine were not quick in developing either. One exception was the greater availability of the more economical and less-polluting diesel engine. Faced with the crisis in the automobile industry, the federal government sought to ease air pollution and safety standards. In this way, the energy crisis blunted enthusiasm for more stringent air pollution laws. However, the mandated 55-mile-an-hour national speed limit and the decline in gasoline usage (by more than 5 percent) contributed to some reductions in air pollution.

Despite the mixed signals about the chance for cleaner air—more regulation, more technology, but also more vehicles and more gasoline usage—progress was made in reducing some forms of air pollution by the late 1980s. Carbon monoxide, hydrocarbon, and nitrogen oxide emissions began to decline. Lead usage in gasoline dropped by 99 percent between 1975 and 1988. Yet 44 urban areas failed to meet ambient air standards for carbon monoxide, and 101 urban areas failed to meet air standards for the serious problem of ozone.

The Clean Air Amendments of 1990—debated vigorously in Congress especially by those who feared a watering down of standards and others who did not want more teeth in the older law—substantially revised the 1970 and 1977 acts. Two of the eleven titles focused particularly on transportation. They involved a new plan to classify cities according to the severity of their emission problems and their degree of attainment of earlier goals, with different levels of action required for each category. The categories were: marginal, moderate, serious, severe, and extreme. For example, “marginal areas” for ozone had to complete an emissions inventory and reduce volatile organic compounds emissions (reductions from other federal programs could be credited toward those reductions). Urban communities classified as “nonattaiment areas” were required to take more substantial actions.

The new law also set more stringent emissions standards for automobiles and some trucks for model years 1996 to 2003. Efforts to tighten exhaust standards essentially ratified innovations underway in California (referred to as a Phase I strategy) and being enacted by other states. The automobile industry, for its part, was already making good progress toward the California standards. However, the administration of George H.W. Bush strongly opposed more stringent exhaust standards like those to be implemented in California (Phase II) in 1996. Instead, it promoted a “clean fuels” and a “clean car” alternative, which mandated the use of new fuels (reformulated gasoline, methanol, ethanol, and natural gas) and the introduction of cleaner cars in cities with the worst ozone problems. Predictably, the oil and automotive industries strongly opposed the “clean fuels” and “clean car” strategies, but they accepted a diluted version rather than be forced to accept something similar to California ’s Phase II exhaust standards.

Despite the lukewarm provisions for cleaner cars, the new policy helped to stimulate interest in alternatives to the standard internal combustion engine. Some movement in this direction had occurred during the energy crisis and earlier with the rotary engine and other technologies. Also, under certain conditions some electric-powered vehicles were in use, especially in urban settings. Cars equipped with electric batteries or hydrogen fuel cells (zero emission vehicles or ZEVs) and even hybrid systems (sporting a combination of electric and gasoline power) were back on the drawing board and some even entered the market. For example, Amory and Hunter Lovins of the Rocky Mountain Institute promoted the development of a “Hypercar,” an aerodynamically designed vehicle powered by a small electric-generating engine utilizing gasoline, liquid gas, or hydrogen cell. The Lovinses also have promoted various forms of a hydrogen-powered vehicle.

Legislation and technical fixes were a start in the battle for clean air, but no magic solutions were achieved overnight. The automobile and oil industries continued to resist tougher standards. The public paid homage to clean air but resented carrying the burden of responsibility through higher costs and reduced automobile performance. Cities groped with ways to keep air quality from diminishing further. But as long as Americans cherished the automobile, emissions problems would remain. The intimacy between the individual and an energy source was nowhere more apparent than in the relationship between Americans and their cars.

Small, imported cars made in-roads into the American market beginning in 1957, while American automobile manufacturers concentrated on bigger vehicles with larger engines. The Big Three—GM, Ford, and Chrysler—were not convinced that a large enough market existed for small cars. As long as gasoline was abundant and cheap, they would produce more powerful automobiles. High-compression engines offered greater horsepower and quicker acceleration for highway travel. Automatic transmissions—an option on 91 percent of the cars sold by 1970—made driving easier. These were luxuries of a high-octane age, luxuries to which the Big Three committed their futures. The side effects of more cars, bigger engines, and automatic transmissions, however, were loss of fuel economy and increased air pollution.

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Environmental Cost of the Automobile Production Process
Energy Use and the Internal Combustion Engine
Auto Emissions and Air Pollution
Noise, Visual Pollution, and Derelict Cars
The Automobile's Imprint on the Landscape
Suburbanization and the Automobile

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