Social and Economic Aspects of Air Quality

THE SOCIAL AND ECONOMIC IMPACTS OF

MOBILE SOURCE POLLUTION ON PUBLIC HEALTH IN

GREATER BEIRUT, LEBANON[1]

PHASE I

1.INTRODUCTION

1.1Motivation

The distribution of pollutants across regions and their effects on economic activity have been the subject of many studies. Research indicates that pollutants impose a wide range of adverse effects on economic activity, directly or indirectly, through variety of channels. Numerous studies confirm the existence of a close association between health, as measured by mortality and morbidity rates, and air pollution.[2] Health problems associated with exposure to pollutants often necessitate expenditures on health care, absence from work, and, in extreme cases, cause permanent disability or death. A review of the literature reveals that approximately four percent of the death rate in the United States can be attributed to air pollution.[3]

Pollutants can also have damaging effects on materials and vegetation through influencing deterioration rates of materials and agricultural productivity of land.[4] Finally, pollutants impose aesthetic damages ranging from reduced atmospheric visibility to reduced property values.[5]

Improvements in environmental quality would mean reducing the magnitude of these adverse effects. Investigation of the quantitative significance of these effects is integral to the formulation and implementation of environmental policies aimed at improving quality of life.

1.2Objectives of the Study

Considering the growing concern over environmental quality deterioration in Lebanon, the scarcity of resources competing for different social programs, and the possible welfare implications of reduced environmental amenities, this study investigates the effects of air pollution from mobile sources on public health in the Greater Beirut Area (GBA). Towards this end, the following research questions are raised:

  • How serious an economic and social problem is air pollution from mobile sources in Beirut?
  • What is the impact of air pollution on health?
  • What is the total annual social cost of air pollution on health in Beirut?
  • What are the policy options available for mitigating mobile source pollution?

1.3Methodology

In order to investigate the effects of air pollution from mobile sources on public health, a three-step multidisciplinary effort is carried:

Step 1:Measurement and modeling of air pollution due to motor vehicles in GBA

  • Collect data on ambient air quality.
  • Estimate mobile source emission rate and total emissions for:
  • Particulates (PM10)
  • Carbon monoxide (CO)
  • Nitrogen Oxides (NOx)
  • Hydrocarbons (HC)
  • Lead (Pb)
  • Estimate the levels of secondary pollutants formed:
  • Ozone

Step 2:Determination of the quantitative relationship between pollutants and public health

  • Obtain concentration/response functions that link levels of ambient air pollution to health damage.

Step 3:Estimation of the effects of air pollution on public health in Beirut

  • Gather data on human health.
  • Mortality
  • Morbidity
  • Assess the magnitude and value of health damages due to existing levels of ambient air quality.
  • Cost of premature death
  • Cost of illness
  • Estimate the monetary benefits to the society from changes in the level of air pollution.
  • Restoring foregone earnings
  • Reduced cost of illness and treatment

1.4Choice of Country Case Study Theme Area

1.4.1Rationale

Lebanon chose to investigate the economic and social impacts of air pollution from mobile sources on public health in Greater Beirut. Mobile source pollution represents one of the most pressing public health issues facing urban areas in Lebanon. This activity complements several studies funded by the World Bank on the state of the environment in Lebanon.[6]

Transportation systems, used for moving people and goods, have various socio-economic benefits and significant impacts on the daily life, and in some cases transportation systems are used as living- standard reference index for the degree of development of nations. However, these systems have undesirable impacts on the environment since, in addition to the noise they produce, motor vehicles emit effluents that are involved in a wide variety of chemical, physical, and health impacts on the surroundings.

The transportation sector worldwide has witnessed continuous growth since the turn of the century. In 1950, there were about 53 million cars on the world’s roads; only four decades later, the global car fleet is over 520 million, an almost ten-fold increase. On average, the fleet has grown by about 9.5 million cars per year over this period. It is estimated that up to 37% of total energy consumed is used for transportation purposes and hence its impacts on the environment are being brought to the attention of the public in many countries.

Besides the transportation sector, the power industry, mainly thermal power plants that use fossil fuels, is regarded as a major source of air pollution. Figure 1.1 shows the contribution of the transportation and power sectors to air pollution.

Figure 1.1: Air Pollution Main Sources

1.4.2Background Information

The demand for passenger cars in Lebanon, like in any other community, is affected by many factors including lifestyle, income, labor structure, cost of fuel, and urban development patterns. These parameters have been changing over the past two decades due to the drastic developments, both political and social, that took place in the country. However, confirmed statistics have shown that the size of the transportation sector, particularly personal transport, has been on the increase. As a result, the energy use for transport has been growing and so have the pollution problems caused by the combustion processes inside various types of engines. The increasing demand for fuel for transport in Lebanon is clearly reflected in the statistics on fuel import over the last thirty years as shown in Figure 1.2.


Figure 1.2: Fuel Imports to Lebanon during the Last Three Decades

In Lebanon, the first car put in use was in 1905, and at the eve of independence in 1943, around 3,400 cars were on roads. This number kept increasing until reaching more than 1,300,000 cars at the end of 1997 according to official figures. Over 50% of the cars operate in the capital city Beirut and its suburbs. This is causing serious traffic and air and noise pollution problems in a densely populated region. Figure 1.3 shows the trend in the number of vehicles operated in the Greater Beirut Area. It should be noted that army vehicles, which account for around 7% of the total number, are not included in these figures.

Figure 1.3: Historical Vehicle Growth in Greater Beirut Area

With an estimated population of around 3.5 million, the car ownership rate in Lebanon is around 0.3 cars/capita which is considerably high in comparison to other countries, even those with higher living standards.

The Lebanese fleet of motor vehicles can be described as being relatively old and poorly maintained. This certainly leads to more emissions of various pollutants than from properly inspected and tuned engines. Other land transport means such as railways are non-existent. Even public transport in urban areas is still in the early stages of rehabilitation.

One consequence of this sizeable and poorly- maintained fleet is that most of the urbanized areas in Lebanon have been experiencing serious pollution problems. In fact, available data indicate the potential for significant health problems associated with poor air quality.[7]

  • The estimated maximum hourly carbon monoxide concentrations in the vicinity of some main roads during rush hour traffic are likely to approach or exceed WHO guidelines for health.
  • Total lead emissions from vehicles deposited in the atmosphere may also cause significant health problems.
  • Over 70% of total NOx emissions are attributed to mobile sources.
  • Particulate emissions from vehicles are at high enough levels to cause damage to health.

While rush hour traffic contributes most to the general level of pollution in the city, there are several factors to take notice of:

  • The predominance of passenger cars on the road: A survey of vehicle classification in the GBA, for the period 1991-1996 revealed that about 88% of registered vehicles are passenger cars, 8% are buses and trucks (10 times more trucks than buses), and 4% other types of vehicles such as motorcycles.[8]
  • The age distribution of the vehicle fleet: Available data indicate that a significant proportion of the fleet of passenger cars is old. A positively skewed distribution with about 70% of the private car fleet of model 1984 or older.[9]
  • Improper maintenance: The car fleet is poorly maintained due to the lack of strict and effective annual checking. This leads to low fuel combustion efficiencies and consequently higher emissions from the exhaust, and higher noise levels.
  • Vehicle testing system: Although there is a system for vehicle testing which requires that vehicles be serviced and tested each year, this is often done in exchange for cash payments without the owner ever presenting the vehicle for inspection.
  • The widespread use of leaded gasoline: The leaded gasoline in Lebanon contains high levels of lead ranking among the highest in the world.[10] Although unleaded gasoline was introduced in 1993, it represents only 12% of all gasoline consumed.[11] The unleaded fuel’s share of the market has increased from 8% of the gasoline imported in 1996 to 12% in 1997.
  • Road network: The conditions of the road network have drastically deteriorated during the war years due to the lack of professional maintenance, illegal encroachment, and lack of technical resources at relevant departments.
  • Scarcity of parking spaces: Major cities and urbanized regions suffer from the lack of parking lots in commercial as well as residential regions. This is reflected in having cars left along roads sides thus further reducing the already limited area allocated for traffic.
  • Traffic management: Traffic light signals were completely destroyed in all cities, and especially in Beirut, a matter that led to permanent traffic jams at major intersections. The Government is in the process of re- instating new traffic signals. Meanwhile, the Police Department Traffic brigade that is a part of the Ministry of Interior conducts traffic control.
  • Tower blocks: Air pollution caused by the transportation sector is excessive in major Lebanese cities than in other countries because tower blocks in which most Lebanese live are situated on both sides of the streets. This leads to high emissions concentration due to the lack of sufficient natural ventilation.

Obviously, many of the problems can be solved via engine modification, fuel switching, gasoline reformulation, and removal of lead from gasoline. There are also great possibilities for using price incentives to help switch from the more polluting to less polluting modes of transport and fuel use.

1.5Organization of the Report

Chapter 2 of this report presents the types and general effects of pollutants that are emitted from motor vehicles. Chapter 3 presents the sampling processes used to measure the actual levels of pollutants and the models used to estimate the concentration levels of the above listed pollutants. Chapter 4 presents a comprehensive review of the literature pertaining to the relationship between pollutants and public health. The objective of the literature review is to obtain an average concentration/response function that can be used to link the levels of pollution concentration in Beirut to certain health outcomes. Chapter 5 presents estimates of the economic cost of health damages due to pollution from mobile sources. The economic cost includes direct hospitalization costs for treatment from diseases that are provoked by air pollution, cost of absenteeism, and cost of premature death. Chapter 6 presents the full range of policy options available to mitigate mobile source pollution in Lebanon. A discussion of the shortcomings of the study and the agenda for future research in Chapter 7 concludes the report.

2.POLLUTANTS: TYPES AND EFFECTS

2.1Introduction

The complete combustion of fuel inside motor vehicle engines produces mainly carbon dioxide, nitrogen gas, and water. Whereas carbon dioxide contributes to the global warming, the other two products are of minor or no impact on the environment. In practice, however, the combustion is not complete and fuel is partially burnt giving effluents such as hydrocarbons, carbon monoxide, oxides of nitrogen, and carbon in the form of soot. The emission of these gases and particulates from the exhaust into the atmosphere has rather severe impacts on human health and on the environment. The main pollutants emitted or formed from motor vehicles are classified as primary or secondary. The objective of this chapter is to discuss the types and the effects of mobile source pollutants.

2.2Primary Air Pollutants

The primary pollutants emitted from the transportation sector are particulate matter, oxides of nitrogen, carbon monoxide, carbon dioxide, hydrocarbons, volatile organic compounds, and lead. Most of the following information is extracted from a recent comprehensive review published in 1996.[12]

Particulate Matter: Particulate matters, or particulates, refer to “a mixture of solid and liquid particles suspended in the air.”[13] Particulates emerge from smoke stacks and motor vehicles exhausts and enter the atmosphere in the form of fine solid particles of diameters ranging from 0.002 to 500 m and contain a wide variety of water-soluble and insoluble components.

Typical mass concentrations vary from 10 g/m3 in non-urban areas, to 200 g/m3 in heavily polluted places. Particulates with diameter less than 10 m are of major concern since they are difficult to filter, can penetrate deep into the body, and can settle in the atmosphere so slowly that they become airborne and tend to migrate for long distances before settling into the ground. In 1987, the United States Environmental Protection Agency (USEPA) restricted the National Ambient Air Quality Standards (NAAQS) to the mass concentration of inhalable particles of 10 m aerodynamic diameter or less (PM10). A 24-hour standard was set at 150 g/m3 and an annual 24-hour standard set at 50 g/m3. In 1997, the USEPA revised the 24-hour standard to 65 g/m3.

Studies show that short-term increases in morbidity and mortality following severe air pollution episodes are linked to high concentrations of particles. This is confirmed more recently even with lower concentrations in different countries and cities. Excess deaths, mainly due to respiratory and cardiovascular diseases, are closely associated with levels of particles. This is true using different indicators of particulate pollution: Black Smoke, Total Suspended Particulates (TSP), Coefficient of Haze (COH), particles of 10 m diameter or less (PM10), and particles of 2.5 m diameter or less (PM2.5). Particle exposure is associated with increased hospitalization for respiratory illnesses and with other aspects of respiratory morbidity (emergency room visits, respiratory symptoms severe enough to restrict activity, cough, acute changes in pulmonary function tests (PFT), asthma, and increased use of medications). Chronic respiratory health effects, such as chronic obstructive pulmonary disease (COPD), also increase with increases in PM10.

Soot, one kind of particulates, is made of unburned hydrocarbons and carbon and these apparently have no direct impact on health. However, when combined with nitrogen oxides in the presence of sunlight, they are transformed into photochemical smog.

The specific biologic mechanisms for increases in mortality and morbidity are not clear. Toxic effects of particulates may be determined by the physical and chemical nature of the particle itself, and by the physics of its deposition and distribution in the respiratory tract.

Oxides of Nitrogen: Oxygen reacts with nitrogen under high temperature combustion to produce different nitrogen oxides, mainly nitrous oxide (NO) that is transformed into nitrogen dioxide (NO2). NO2 is a brown color gas obtained from the oxidation of NO. It attacks the hemoglobin that carry O2 to the blood. It causes material corrosion and may react with hydrocarbons in the presence of sunlight to produce photochemical smog. Typical emission rate is 2.5 g/km and this value increases with increasing speed. NO2 is highly reactive and it is the precursor to the formation of ozone (O3). However, unlike O3, NO2 exposure at near-ambient levels (< 2 ppm) does not cause a significant influx of poly-morphonuclear cells (PMN) into the airways and alveoli, i.e., it causes less lung inflammation. Nitrogen dioxide has an oxidative capability and interacts with the lower bronchial airways. However, the evidence for its effect on pulmonary function tests (PFT) and airway reactivity is not very strong.

A few studies report a decrement in PFT after exposure to low concentrations of NO2 during exercise but not at rest. Asthmatics and subjects with COPD are more susceptible than normal individuals, especially the former. Decreased immunity and preponderance to infections is reported in a few animal, but not clinical, studies.

As for respiratory illnesses, one study reports more of them in a residential area with high exposure to NO2. However, no exposure gradient response is detected. Another study shows increased bronchitis among children living for 2 or 3 years in intermediate and high exposure areas, but illnesses can not be attributed unequivocally to NO2. Residence in homes with gas stoves are shown in one study to be associated with an increase in the frequency of respiratory symptoms and of respiratory illnesses in children of 2 or less years of age, but a prospective study that compares the respiratory health of people who own gas versus electric stoves reports no consistent trends.

The Harvard Six Cities study reports a monotonic increase in respiratory symptoms (shortness of breath with wheezes, chronic wheezes, cough, phlegm, and bronchitis) with increase in NO2, but other studies report less striking findings.

Carbon Monoxide: Carbon monoxide (CO) is the most abundant of all pollutants emitted from the transportation sector. It is a colorless, odorless, and tasteless, but a very poisonous gas that results from the incomplete combustion of carbon-containing fuels. Up to 75% of CO emissions to the atmosphere comes from motor vehicles. CO is regarded as localized pollutant that has high concentrations in areas of heavy traffic and closed spaces such as underground parking areas and tunnels. Typical emission rates for CO are in the range of 35 g/km for an average size motor vehicle, and are found to decrease with increasing engine speed.