Along with tackling the environmental and health problems at the household and community level, perhaps the next greatest opportunity for improving both environmental quality and human health is to reduce air pollution and carbon dioxide (CO2) emissions from the burning of fossil fuels. Energy-related environmental pollution figures prominently as a contributor to a number of diseases, including acute respiratory infections, chronic respiratory diseases, cardiovascular diseases, and cancer. Exposure to urban air pollution remains a widespread and serious environmental problem worldwide (98). Less certain but no less pressing, the potential health impacts resulting from global climate change loom on the horizon. On the positive side, tremendous health benefits and economic savings may be gained if the links among energy, air pollution, and climate change are dealt with in a coordinated way.
An estimated 1.4 billion people are exposed to unhealthy outdoor air (99). Especially in the developing world, where maximum particulate and SO2 concentrations in many cities still exceed WHO guidelines 10-fold, air pollution poses a clear danger to public health. In the developed world, although levels of pollution tend to be lower and episodes of extremely severe air pollution have been relegated to the history books, air pollution still remains a problem in many cities. In the United Sates, for instance, particulate air pollution is believed to contribute to about 50,000 to 60,000 deaths each year, primarily through respiratory or cardiovascular disease (100) (101).
Improved monitoring and tightening of air quality standards and regulations remain top priorities for developed and developing countries alike. In the United States, the Environmental Protection Agency (U.S. EPA) recently tightened the national air quality standards. Although the United States has seen dramatic improvements in air quality over the past 20 years, these standards are designed to further reduce the health risks of small particulates and ozone, especially for children, the elderly, and people with asthma or other respiratory diseases (102). Several cities in the developing world, including Bangkok, Santiago, and Bombay are all in the process of tightening air quality standards and improving monitoring and enforcement efforts (103) (104) (105).
Nevertheless, these regulatory approaches will likely be inadequate to address the energy-related problems of air pollution and climate change. What is needed, instead, in countries of all levels of development, are ambitious, forward-looking strategies to reduce energy consumption. Avenues for intervention range from energy pricing, to curbing urban sprawl, to investing in alternative transportation options, to increasing the energy efficiency of products and processes.
Given the complexity of the problem, strategies for reducing air pollution must be tailored to a particular city, bearing in mind both the key contributors and the city’s priorities and resources. In those cities that are still industrial centers, for example, controlling industrial emissions of SO2 and particulates should be a high priority. The Bangkok metropolitan region alone, for instance, is home to nearly three quarters of Thailand’s manufacturing industries. Similarly, industry is concentrated in many large cities in India, Indonesia, Mexico, the Philippines, and the Republic of Korea (106).
In other cities, reducing emissions from the use of coal for domestic heating and power generation should be of greatest concern. In Central and Eastern Europe, China, and India, for example, the use of coal contributes a large share to outdoor air pollution, especially in terms of SO2 and particulates. Emissions of SO2 and particulates can be reduced by as much as 99 percent and nitrous oxide (N2O) emissions can be reduced by as much as 90 percent through the use of clean coal technologies (107). Coal preparation – which consists of processes that range from mechanical sorting that yields pieces of uniform size to treating the coal to remove ash, sulfur, and moisture – can also help to reduce emissions at relatively low cost (108).
Switching from coal to natural gas can also improve local air quality. In the Czech Republic, for example, Czech Energy Works reduced SO2 emissions by 36 percent, dust and particulate emissions by 49 percent, and N2O emissions by 50 percent between 1989 and 1995. These reductions were accomplished by installing scrubbers on coal power utilities and switching to natural gas and oil for home heating (109). Although air pollution still exceeds WHO health guidelines, the Czech Republic believes that within 7 or 8 years it can achieve levels of air quality that Western Europe took 20 years to achieve (110).
Cars and other vehicles are another major contributor to urban air pollution. The problems associated with using leaded gasoline were discussed earlier. Motor vehicles also emit a variety of other pollutants, including particulates and SO2. As the demand for cars grows, emissions can be expected to worsen unless there are dramatic improvements in fuel efficiency and vehicle technology. Indeed, the number of vehicles in Chian has been growing at an annual rate of almost 13 percent for 30 years, nearly doubling every 5 years. India’s fleet has been expanding at more than 7 percent per year (111).
Especially in developing countries, where cars tend to be old and polluting, tackling the problems of motor vehicle emissions can have immediate and positive impacts on health. Investments in cleaning up the worst offenders can reduce pollution significantly at relatively low cost. In Manila, for instance, cleaning up the dirtiest vehicles alone could save an estimated 160 deaths and 4 million respiratory symptom days each year. (112) Similar benefits have been estimated for Bombay and Jakarta (113) (114). Cutting the sulfur content of diesel and gasoline can also greatly reduce both SO2 and fine particulate concentrations (115).
Although these measures can significantly reduce concentrations of conventional pollutants, they do not address the inherent problems of a transportation system that is based on the private car. After more than 30 years of rigorous regulation of automobile emissions and fuels, the U.S. Government estimates that, by 2005, automobile emissions in the United States will begin to rise again as the result of increased travel and the switch to gas-guzzling minivans (116). One of the greatest opportunities for developing countries–where car ownership is still relatively low–is to implement policies that encourage alternative transportation systems. Policies that raise the price of auto fuel or car ownership, for instance, would help curb urban sprawl and make public transportation, bicycles, and walking more attractive options. As the experience of many developed cities has shown, once automobile ownership drives out these alternatives, they are almost impossible to institute (117).
In 1995, the International Panel on Climate Change (IPCC) concluded that the cumulative effects of anthropogenic CO2 emissions were having a discernable impact on the environment (118). As Changing Environments, Changing Health: Rising Energy Usedescribed, changes in the global climate may affect human health in myriad ways, ranging from deaths and injuries linked with an increased frequency of severe storms to increases in vector-borne diseases. Although the exact health effects remain uncertain, their potential scale provides added weight to the case for reducing CO2 emissions.
Scientists estimate that global emissions of CO2 need to be reduced to well below 1990 levels to eventually stabilize the atmospheric concentrations of greenhouse gases at a safe level (119). This task will require a major restructuring of the global energy supply, away from the use of coal and oil and toward natural gas and renewable energy sources. Buildings and transportation systems, as well as industrial processes, will need to be redesigned to use energy much more efficiently. Undertaking these measures will entail difficult political decisions and economic costs. As negotiations in Kyoto in late 1997 made abundantly clear, these issues are not easily solved. Intense debate continues not only about desirable goals and timetables, but also about the relative roles of developed and developing nations in the effort to curb emissions. (See Global Commons.)
Without question, reducing fossil fuel consumption will require raising the price of these fuels. Fossil fuel prices remain unreasonably low in most parts of the world. Electricity, natural gas, and coal are subsidized in most countries; petroleum consumption is subsidized in oil-exporting developing nations. Until prices more truly reflect the costs of using fossil fuel – including the health costs from air pollution and costs of environmental degradation – few policy measures will stem the growing use.
Such changes are neither simple nor straightforward, however. Energy, like water, is a vital resource that is essential to human well-being and economic development. That recognition underlies policies that subsidize its use. Providing power to a remote area brings enormous opportunities to people, which is one reason energy has historically been subsidized. Refrigeration, to use just one example can save many lives from foodborne illness. If prices are to be changed, these immediate benefits must be weighed against the more hidden costs of environmental degradation and future health damages.
In addition, once energy prices have been set in a particular range, they can be difficult to alter. Although economists and consumers may agree in principle that energy prices should better reflect the true costs, consensus breaks down rapidly in setting a specific goal–such as raising the price of gasoline. Reducing energy subsidies and adjusting energy prices may cause negative short-term consequences for some, and perhaps substantial economic impact, so political opposition seems certain.
Even so, some countries have made considerable progress in reducing energy subsidies over the past several years. Between 1990 and 1996, total fossil fuel subsidies in 14 developing countries declined by 45 percent, from US$60 billion to about US$33 billion. Brazil, China, India, Mexico, Saudi Arabia, and South Africa all cut fossil fuel subsides significantly. During this same period, subsidies in developed countries declined by 20.5 percent, from US$12.5 billion to US$9.9 billion. In China, price reform has led to significant energy efficiency gains–gains that, according to the World Bank, have the potential to yield savings of 1 to 1.7 billion metric tons of coal equivalents per year by 2020, an amount greater than China’s total energy consumption in 1990 (120). Although these cuts were made to meet economic, social, and public health needs, they nevertheless have contributed to significant carbon savings (121).
A carbon tax is currently the subject of heated debate. A carbon tax would reduce emissions of certain air pollutants by increasing the costs of fuels according to their carbon content, carbon being a proxy for emissions. For example, coal would be taxed more heavily than natural gas, because coal’s carbon content per British thermal unit (Btu) is higher than that of natural gas. Advocates of the carbon tax believe it would be a strong tool for preventing global climate change and would also reduce energy consumption and lower conventional pollutants. So far, only five countries – Denmark, Finland, the Netherlands, Norway, and Sweden – have implemented carbon taxes (122).
To date, the benefits of reducing greenhouse gas emissions have been generally considered in the context of long-term gains. In other words, investments now can avert harmful effects later. What has often been overlooked, however, is the immediate improvement that would occur in terms of reductions of ambient air pollution–with benefits to ecosystems, economies, and human health. Indeed, efforts to reduce CO2 emissions will lead to measureable reductions in particulates, SO2, and other airborne toxic compounds, with consequent and immediate improvements in air quality and human health, according to a recent analysis by a working group established by WRI and WHO. This study suggests that the same policies that will avert greenhouse warming in the long term will save hundreds of thousands of lives. Specifically, the study found that under a relatively stringent climate policy scenario–a 15 percent reduction in developed country emissions by 2010, with smaller reductions in developing nations–an estimated 700,000 deaths per year could be avoided by 2020 (123).
Because the exact effects of a warming planet remain uncertain, it can be difficult for nations to take actions that cause economic pain today. Yet, this recent study illustrates how preventive environmental strategies can yield multiple payoffs–not only in terms of reducing immediate- and long-term health damages from air pollution but also in averting ecological disruption and the economic costs predicted to accompany a warming planet.
In summary, the range of interventions and policies described in this chapter is by no means exhaustive. Nor does this chapter attempt to describe the complex choices and trade-offs that will be necessary to implement policies on a local level. Effecting change, admittedly, is difficult. Policymakers typically confront competing demands and priorities and are handicapped by myriad financial and technical constraints. At the same time, however, the benefits of the changes outlined here promise to be substantial, not only in terms of improving public health but also in preserving environmental quality and ensuring equitable development.