Air quality and health

Transcription

1 Air quality and health Theme story: Act now for the Blue Sky! What kind of sky do you want to live with? Looking at the sky, we would occasionally find the sky covered by smog, appearing grey and hazy. This is a precise warning to us about the problem of air pollution. In order to fulfill the demands in life, such as the use of electricity, transportation and various production activities, exhaust gas and pollutants are produced inevitably, resulting in poor air quality in our cities and adverse impact on our health. Similarly, London, Los Angeles and other metropolises are also facing this challenge. The Organization for Economic Cooperation and Development has stated in its report published in March 2012 that by the year 2050, 3.6 million people could end up dying from air pollution-induced respiratory failure every year. At present, the Hong Kong Government monitors the situation of air quality through the Air Quality Health Index, reminding the public to reduce physical exertion and outdoor activities in order to protect their health whenever necessary. Do you wish to recover a clear, blue sky? If reducing the use of electricity, vehicles and goods that release pollutants will cause inconvenience to your life, are you willing to change your habits? Return the blue sky to me takes not only effective management strategies by the Government, but also our effort and cooperation to make it comes true. 129

2 This chapter will provide resources to teachers for guiding students to think about these issues and discuss what strategies and measures should be taken to manage air quality in the city from the perspective of sustainable development to recover the blue sky. Chapter summary The development of cities and industries, as well as modern lifestyle, produce air pollutants inevitably. If the situation gets serious, it would even threaten human health. Facing the problem of air pollution, Hong Kong and the whole world are required to take effective management strategies to improve air quality. Under such circumstances, what kind of air quality management strategies should Hong Kong adopt? This chapter will offer resources to help students understand the following issues: Definition and causes of air pollution; International air quality standards and solutions of respective countries; Situation of air pollution in Hong Kong; Current air quality management strategies in Hong Kong. 130

3 Teaching arrangements Modules Energy technology and the environment + Public health + Globalisation + Modern China + Hong Kong Today Learning goal Understand the causes and effects of air pollution Grasp the problem, testing and coping strategies of the air quality of Hong Kong Think about how Hong Kong could improve air quality from the perspective of sustainable development Discussion 1. What are the causes and the major influences of air pollution? 2. How is the situation of air pollution in Hong Kong? How do Hong Kong s natural and cultural characteristics affect the urban air quality? 3. What are the impacts of air pollution on Hong Kong people s health? 4. What policies and measures has Hong Kong taken to tackle air pollution? Do these policies and measures conform to the principle of sustainable development? Suggested learning time Nine sessions (40 minutes each). If lesson duration is one hour, it is recommended to reschedule to eight sessions. Generic skills Critical thinking, studying and learning, cooperation Values and attitudes Responsibility Active participation and simplicity 131

4 Suggested teaching sequence Station 1 Station 2 Station 3 Station 4 Preparation activity Knowledge building (1): Knowledge building (2): Learning activity: Life Survey: Have You Ever What is air pollution? Air Quality Objectives Survey of Public Opinions on Felt Uncomfortable? Teaching period: 1 session Teaching period: 1 session Hong Kong Air Quality Teaching material: Survey Worksheet Teaching materials: Background Information(1), Teaching materials: Background Information (2), Teaching period: 2 sessions Teaching material: PowerPoint (1), PowerPoint (2) Learning Activity Worksheet Worksheet (1) Station 5 Station 6 Station 7 Station 8 Knowledge building (3): Knowledge building (4): Learning activity: After class revision and extension Overview on Hong Kong s air pollution, its impacts and coping strategies International experiences in tackling air pollution No-waste, is it possible? Teaching period: 3 sessions activities: Revision and reflection Teaching period: 1 session Teaching materials: Background Information (3), PowerPoint (3), Worksheet (2), Data-based Questions Worksheet (1) Teaching period: 1 session Teaching materials: Background Information (4), PowerPoint (4) Teaching materials: Discussion Worksheet, PowerPoint (5) Teaching materials: Revision worksheet, Reflection Worksheet 132

5 Cross-module structure Air quality Globalisation Modern China Hong Kong Today Air pollution has become a global The environmental challenges Acknowledge the natural and cultural constraints issue beyond the control of arising from economic in Hong Kong, such as limited land area, high individual governments and affects human health. The establishment, imposition and coverage of the global and transnational Air Quality Objectives. Facing the problem of global air pollution, Hong Kong should adopt development in the Pearl River Delta region after the Chinese Economic Reform. Regional cooperation and development planning, such as Hong Kong-Guangdong cooperation to deal with air pollution. population density, densely located buildings, and narrow roads with heavy traffic, etc. Recognise how all these factors cause air pollution and affect people s quality of life. Recognise the relationship between the lifestyle of Hong Kong citizens and air pollution, and the resulting societal and political responsibility and participation; Personal Change the habits and try to minimise the activities which generate air pollutants and the use of related products. feasible measures and strategies to As a major city of China, Hong Understand the demands of different people/sectors/ reduce emission of air pollutants Kong is able to demonstrate how interest groups for air quality management, and how and improve air quality. to balance development and air the Government s strategies respond to these demands. quality, which is important to China s environmental policy. 133

6 Station 1: Preparation activity Survey: Have you ever felt uncomfortable? Name: Class (Student ID): ( ) Indoor and outdoor air pollution Air pollution can be divided into outdoor air pollution and indoor air pollution. Outdoor air pollution refers to air pollutants in outdoor area, such as streets and roadside. Its major sources include exhaust gas emitted by vehicles, smoke emission from factories, etc. (Wright, 2005). Indoor air pollution refers to air pollutants in households, offices and buildings areas (Indoor Air Quality Information Centre, 2012). Its major sources include the burning of fuels in gas stoves and ovens, chemical substances originated from the ageing of furniture, and volatile organic compounds from spray, etc. (Botkin & Keller, 2011; Indoor Air Quality Information Centre, 2012). Investigation (1) Your own experience Have you ever encountered air pollution? If yes, please describe your experience, including the sources of pollution, the environment at that time, and your physical condition and feelings. Have you ever caused air pollution in your daily life? If so, please list the relevant acts. (2) Interview at least three people in school or in the community to see whether they have uncomfortable experiences due to air pollution in daily life. (3) Identify the causes and sources of their uncomfortable experiences. (4) Try to find a solution or a soothing method accordingly. Reference: Botkin, Daniel B. & Keller, Edward A. (2011), Environmental Science: Earth as a Living System (8th ed.) Hoboken, N.J.: Wiley. Wright, Richard T. (2005), Environmental Science: Toward a Sustainable Future (9 th ed.), New Jersey: Pearson. Indoor Air Quality Information Centre (2012), Sources of IAQ Pollutants. Retrieved from 134

7 Your own experience: 135

8 Profile of respondents Uncomfortable experience (such as location, time, symptoms, surrounding environment, etc.) Causes and sources of discomfort Name: Background: Name: Background: Name: Background: 136

9 Solution or soothing method 137

10 Station 2: What is air pollution? Background information (1) What is air pollution? According to the data from the Division of Sustainable Development of the United Nations and the Victorian Government in Australia, air pollution is formed when air pollutants in a particular environment have accumulated to a level that may cause biological harm (UN Division of Sustainable Development, 2004). Teaching tips In order to enhance students motivation to learn, teachers may consider using Worksheet (1) to carry out activities before teaching. Teachers may first distribute Worksheet (1) and show the comics in PowerPoint (1). Based on the worksheet, teachers may ask students to point out the sources of air pollution in the picture, the impacts of air pollution on comic characters, and whether they have similar experiences. Teachers may invite three students to share their views, and then introduce this topic. 138

11 Information for teachers: Major air pollutants (Botkin & Keller, 2011) Total suspended particulates, respirable suspended particulates and fine suspended particulates (TSP, RSP & FSP) Total suspended particulates (TSP) are fine particulates with a diameter of less than 100 micrometres, such as dust, soot, smoke, etc. The major source of TSP in Hong Kong includes vessels, power plants, construction works and vehicle emissions. Suspended particulates with a diameter of 10 micrometres or less are called respirable suspended particulates (RSP), or PM10 for short. The major source of RSP in Hong Kong includes vessels, diesel vehicles and emissions from power plants; RSP are also formed through the photochemical reactions and oxidation of gaseous pollutants. Suspended particulates with a diameter of 2.5 micrometres or less are called fine suspended particulates (FSP), or PM2.5 for short. (WHO, 2006) Sulphur dioxide (SO 2 ) Formed primarily from the combustion of sulphur-containing fossil fuels. Sulphur dioxide in Hong Kong mainly comes from vessels, power plants, and the rest is from fuel burning devices and vehicles. Nitrogen dioxide (NO 2 ) Formed primarily by oxidation of nitric oxide emitted from fuel combustion. Power plants, vessels and vehicles are the main sources of emissions of nitrogen dioxide in Hong Kong, in which nitrogen oxides emitted by vehicles has a greater impact on roadside air quality. Carbon monoxide (CO) Mainly comes from vehicles emissions, and partly from vessels. Ozone (O 3 ) and photochemical oxidants Produced not directly from human activities, but from photochemical reaction between the sun and other pollutants. Since photochemical reaction usually takes several hours to complete, ozone concentration recorded in a region may come from distant regions, therefore ozone is a regional air pollution problem. Lead (Pb) The only toxic air pollutant included within the Air Quality Objectives. It mainly comes from leaded gasoline. 139

12 Relationship between air pollution and urban life Since the Industrial Revolution in 18th century, industrial production, power generation and drive mechanism burned a lot of fossil fuels and emitted Let s think large amount of exhaust fumes and harmful gases, resulting in cities shrouded in smog (Brimblecombe, 2000; Hardoy et al, 2001). In its 2010 State of the Environment Report on the European Environment, the European Environment Agency (EEA) pointed out that emissions from industrial and commercial energy combustion had become the largest source of air pollution in Europe (EEA, 2010; OECD, 2012). With rapid urbanisation and human development, as well as a global population growth of almost 2 billion between 1990 to 2010 (UN Population Division, 2011), the demand for energy consumption, industrial production and transportation rises continuously. Emissions of exhaust fumes, harmful gases and air pollutants lead to serious air pollution. 140 Industrial production, power generation and drive mechanism are all originated from our demands of improvement in living standard. How do these demands lead to the emission of large amount of exhaust fumes and air pollutants? What price do we have to pay for this?

13 The main sources of air pollution are shown in the diagram below (OECD, 2012; Wright, 2005): Main sources of human emissions Industrial and commercial production Household life Smoking and cooking emit large Transportation Vehicles powered by gasoline and Energy generation Combustion of fossil fuels, such Industrial production burns coal and emits large amount of sulphide containing gas. Some stores, such as restaurants, emit respirable suspended particulates and volatile organic compounds during operation. quantities of respirable suspended particulates. Some household products containing volatile organic compounds such as paints, thinners, volatile solvents, etc., produce ozone after photochemical reaction. diesel emit pollutants, such as respirable suspended particulates, carbon monoxide, nitrogen oxide and volatile organic compounds, etc. Chemical reaction of volatile organic compounds and nitrogen oxide takes place to form ozone as coal, diesel, etc., emits large amount of sulphur dioxide and nitrogen oxide. and suspended particulates. Spread of air pollution Pollutants float over long distances, and form turbulence because of the collisions of air with different landforms and other air currents. All these factors make the mixing of pollutants and clean air easier, causing the dispersion of air pollutants to different regions. (Zhang Renfu, 1996) If pollutants have entered indoor area with poor ventilation, the harmful substances in the air will increase continuously, causing indoor air pollution. (Botkin & Keller, 2011) 141

14 Impacts of air pollution Damage to human health According to the statistics of the World Health Organization in September 2011, outdoor and indoor air pollution led to the death of about 1.3 million people and 2 million children each year. About 50% of the fatality of lung inflammation due to indoor air pollution was children under 5 years old. (WHO, 2011; OECD, 2012) The University of Hong Kong reported in its study on the relationship between air pollution and mortality rate in 2011 that air pollution reduces visibility, i.e., for every 6.5 km decrease in visibility, there was a corresponding 1.13% increase in the number of non-accidential deaths, which means an extra of 450 deaths. (The University of Hong Kong, 2011) The World Health Organization has pointed out in June 2012 that emissions of diesel combustion directly increase the risk of lung cancer and bladder cancer and classified diesel as carcinogenic to humans. (Reuters, 2012) Impacts on the quality of life High concentration of air pollutants hinders our vision. If smog has formed, it will affect sunshine. People living in this kind of environment will be directly affected mentally and spiritually in the long term, and thus damaging their quality of life. Visibility in Hong Kong has become poorer in the past few years. One of the reasons is that sunlight has been scattered and absorbed by suspended particulates and nitrogen dioxide in the air. Accumulation of ozone, suspended particulates and other pollutants also form smog and reduce visibility. (Chan, 2011; Reuters, 2011) The Organisation for Economic Co-operation and Development (OECD) has also pointed out that in many European countries, chemical substances released by furniture, carpets and household cleaning products cause serious indoor air pollution, affecting indoor living condition. (OECD, 2012) Secondary pollution Air pollutants can be divided into primary and secondary pollutants. Primary suspended particulates are particulates directly emitted into the atmosphere, which can lead to the emergence of secondary pollutants. (Wright, 2005) Secondary pollutants, such as ozone and some suspended particulates, are formed by chemical interaction of primary pollutants. (OECD, 2012) Aggravation of climate change Industrial production and electricity generation discharge large quantities of exhaust. These emissions not only cause air pollution, but also aggravate carbon emissions as they are the main greenhouse gases. Carbon dioxide and methane are the key greenhouse gases causing climate change at present. Secondary pollutants contain a lot of organic matter, which affect air quality seriously, and are harder to be controlled comparing to primary pollutants. (Hanrahan, 2012) 142

15 Supplementary knowledge Impact of various kinds of air pollutants on health (Botkin & Keller, 2011) Respirable suspended particulates: Sulphur dioxide: Nitrogen dioxide: Carbon monoxide: Ozone: Respirable suspended particulates may enter the lungs and cause respiratory problems. Sulphur dioxide can lead to impairment of respiratory functions. It can also aggravate the condition of patients with respiratory or heart diseases and increase the risk of chronic respiratory illnesses. Nitrogen dioxide can reduce one s ability to resist respiratory diseases and aggravate the condition of patients with chronic respiratory diseases. After entering the blood vessels, carbon monoxide can reduce oxygen delivered to all organs and tissues, which will threaten the health of patients with heart disease. Since ozone is a strong oxidant, it can irritate eye, nose and throat even at low concentrations. High concentration of ozone can increase infection risk of the respiratory system, and aggravate the condition of patients with respiratory diseases, such as asthma. 143

16 How can we tackle air pollution? The importance of air quality management Air pollution is an urgent problem for everyone. But we are in the dilemma of being unable to completely avoid producing emissions and pollutants in order to maintain and fulfill our demands of life. Therefore, it is an important issue to strike a balance between demands of human life and industrial production and the protection of air quality. What is Air Quality Management? According to the United Nations Human Settlement Programme, Air Quality Management means the control and reduction of concentrations and amount of air pollutants, so that the air quality can be maintained at an acceptable level. (UN-HABITAT, 2012) Responses according to the Principle of Sustainable Development and Environmental Justice Sustainable Development We should pay attention to environmental factors and reduce emissions of exhaust and air pollutants, thus to avoid the damage caused exceeding the tolerance limit of the environment. (UN, 1987; ICUN, 2006) While implementing air pollution control measures, we should take into account both environmental and economic factors, balancing people s demand on material well-being and development needs. Air pollution can directly affect human s health, therefore while we are maintaining and enhancing our living standard, we must put the health of people and environment at first place, and try to tackle the air pollution. (Council for Sustainable Development, 2006) We should balance development needs and air quality, and pay the necessary effort to protect the environment (Council for Sustainable Development, 2006). We should affirm the fundamental right of all people to enjoy clean air. (First National People of Color Environmental Leadership Summit, 1991) We should ensure the health of the nature, taking account of the principle of minimum consumption of earth s resources thus to reduce excessive energy consumption and emissions of air pollutants. (First National People of Color Environmental Leadership Summit, 1991) Environmental Justice We should stop using items liable to damage and destroy air quality. (First National People of Color Environmental Leadership Summit, 1991) Air pollution is invisible and has no geographical restrictions, so it can affect other places rapidly. Considering the impact of air pollution to other places, we should reduce emissions of exhaust fumes and pollutants, and protect all people s rights to enjoy clean air (Council for Sustainable Development, 2006). 144

17 Reference: Bolton, Daniel B. & Keller, Edward A. (2011), Environmental Science: Earth as a Living System (8th ed. ) Hoboken, N.J. : Wiley Chan, C. K. (2011), Brieing: HKUST Air Quality Research Supersite, presentation in inauguration ceremony of HKUST Supersite The Council for Sustainable Development (2006): Report of Clean Air and Blue Skies The Choice is Ours. Retrieved from Division for Sustainable Development, United Nations Department of Economic and Social Affairs (2004), Protection of Atmosphere. Retrieved from European Environment Agency (2010), The European Environment State and Outlook 2010: Synthesis, State of the Environment Report. First National People of Color Environmental Leadership Summit (1991): Principle of Environmental Justice. Retrieved from Forster, P. et al. (2007), Changes in Atmospheric Constituents and in Radiative Forcing, in S. Solomon et al (eds.) Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press. Grady Hanrahan (2012), Ambient Particulate Matter: Primary and Secondary Contributions and Formation, in Key concepts in environmental chemistry. Amsterdam: Academic Press, Jorge E. Hardoy et al (2001). Environmental problems in an urbanizing world: inding solutions in Africa, Asia, and Latin America. Pub Info Sterling, VA: Earthscan Publications. OECD (2012), OECD Environmental Outlook to 2050: The Consequences of Inaction. Paris, OECD. Peter Brimblecombe (2000), Urban Pollution and Public Health, Timothy O Riordan (ed.), Environmental Science for Environmental Management, ( ) Harlow, England: Prentice Hall. Reuters ( ), Bad Air Cuts Visibility in Hong Kong, raises Death Rates. Retrieved from Reuters ( ), Diesel exhaust fumes cause lung cancer, WHO says. Retrieved from State Government of Victoria, Australia, What is Air Pollution? Retrieved from The United Nations Human Settlements Programme (2012), Urban Air Quality Management. United Nations (1987), Our Common Future: Report of the World Commission of Environment and Development. Retrieved from United Nations Population Division (2011), World Population Prospects, the 2010 Revision. Retrieved from The University of Hong Kong ( ), HKU Study on Impact of Loss of Visibility on Mortality Risks: A Report of Regional and Global Importance, Retrieved from 145

18 World Health Organization (2006), Air quality guidelines - global update Retrieved from World Health Organization (2011), Air Quality and Health. Retrieved from Wright, Richard T. (2005), Environmental Science: Toward a Sustainable Future (9 ed.), New Jersey: Pearson. Zhang Renfu (1996), Environmental Quality Planning and Management (1) Taibei: ALi Cultural Utilities Corporation Limited. 146

19 Worksheet (1) Name: Class (No.): ( ) Please describe the sources of air pollution and its impact on the comic characters shown in PowerPoint (1). In addition, please state whether you have similar experiences. If yes, please describe them. Sources of air pollution Impact Similar experiences in daily life Comic 1 Comic 2 Comic 3 147

20 Station 3: Air Quality Objectives Background information (2) Air pollution is invisible and without geographical restrictions. Therefore, international organisations and different countries or regions have developed Air Quality Objectives and measurement standard of all kinds of pollutants. They monitor and control the situation of air pollution according to these objectives, which has become an important part of air quality management. International Measurement Objectives The present Air Quality Objectives refers to the updated Air Quality Guidelines published by World Health Organization in 2006 (WHO, 2006). The guidelines have provided a scientific basis for governments of all countries to formulate policies and management strategies of air quality. The guidelines of World Health Organization focused on several major air pollutants, listing their acceptable criterion values (WHO 2006). Supplementary knowledge The Roles and Impacts of the World Health Organization in the Formulation of Air Quality Objectives World Health Organization (WHO) has published Air Quality Guidelines (AQGs) for the whole world, but every country can still come to more suitable arrangement based on its own national conditions and environmental policies. Criteria set by WHO are applicable throughout the world but are not legally binding. (WHO, 2006). Suspended particulates Ozone PM2.5 Annual average concentration is 10 micrograms/cubic meter; 24-hour average concentration is 25 micrograms/cubic meter. 8-hour mean concentration is 100 micrograms/cubic meter. PM10 Annual average concentration is 20 micrograms/cubic meter; 24-hour average concentration is 50 micrograms/cubic meter. Sulphur dioxide 24-hour average concentration is 20 micrograms/cubic meter; 10-minute average concentration is 500 micrograms/cubic meter. Nitrogen dioxide Annual average concentration is 40 micrograms/cubic meter; 1-hour average concentration is 200 micrograms/cubic meter. Source: World Health Organization (2006), Air quality guidelines - global update Retrieved from 148

21 Information for teachers: Measurement standard of major air pollutants according to the World Health Organization's Guidelines Air quality guidelines and interim targets for particulate matter: Annual average concentration and 24-hour average concentration PM10 (micrograms/ cubic meter) 24-hour average concentration (micrograms/cubic PM2.5 (micrograms/ cubic meter) 24-hour average concentration (micrograms/cubic Basis for the selected level (Annual average concentration) Basis for the selected level (24-hour average concentration) meter) meter) Interim target 1 (IT-1) These levels are associated with about a 15% higher long-term mortality risk relative to the AQG level Based on published risk coefficients from multi-centre studies and meta-analyses (about 5% increase of short-term mortality over the AQG value) Interim target 2 (IT-2) Interim target 3 (IT-3) In addition to other health benefits, these levels lower the risk of pre-mature mortality by approximately 6% relative to the IT-1 level In addition to other health benefits, these levels reduce the mortality risk by approximately 6% relative to the IT-2 level Based on published risk coefficients from multi-centre studies and meta-analyses (about 2.5% increase of short-term mortality over the AQG value) Based on published risk coefficients from multi-centre studies and meta-analyses (about 1.2% increase in short-term mortality over the AQG value) Air Quality Guidelines (AQG) These are the lowest level at which total cardiopulmonary and lung cancer mortality have been shown to increase with more than 95% confidence in response to long term exposure to PM2.5 Mortality of cardiopulmonary disease and lung cancer in this level has a significant increase 149

22 Air quality guidelines and interim target for Ozone: 8 hour concentrations High levels Daily maximum 8-hour mean concentration (micrograms/ cubic meter) 240 Basis of level Significant health effects; substantial proportion of vulnerable populations affected. Interim target 1 (IT-1) 160 Important health effects; does not provide adequate protection of public health. Exposure to this level of ozone is associated with: physiological and inflammatory lung effects in healthy exercising young adults exposed for periods of 6.6 hours health effects in children (based on various summer camp studies in which children were exposed to ambient ozone levels an estimated 3 5% increase in daily mortality (based on findings of daily time-series studies) Air Quality Guidelines (AQG) 100 Provides adequate protection of public health, though some health effects may occur below this level. Exposure to this level of ozone is associated with: an estimated 1 2% increase in daily mortality (based on findings of daily time-series studies) extrapolation from chamber and field studies based on the likelihood that real-life exposure tends to be repetitive and chamber studies exclude highly sensitive or clinically compromised subjects, or children likelihood that ambient ozone is a marker for related oxidants 150

23 Air quality guidelines and interim targets for SO 2 : 24-hour and 10-minute concentrations 24-hour average concentration (micrograms/cubic meter) 10-minute average concentration (micrograms/ cubic meter) Basis of level Interim target 1 (IT-1) 125 Interim target 2 (IT-2) 50 _ Intermediate goal based on controlling either motor vehicle emissions, industrial emissions and/or emissions from power production. This would be a reasonable and feasible goal for some developing countries (it could be achieved within a few years) which would lead to significant health improvements that, in turn, would justify further improvements (such as aiming for the AQG value). Air Quality _ Guidelines Guidelines of Nitrogen dioxide (one hour and annual mean concentrations) Air Quality Guidelines One hour average concentration (micrograms/cubic meter) 200 Annual mean concentration (micrograms/cubic meter) 40 Measurement objectives of Hong Kong Hong Kong s Air Quality Objectives The current Air Quality Objectives (AQO) of Hong Kong have become effective since 1 January The Objectives, as a new measurement to pass judgment on whether the city s air quality is qualified, tighten the restriction of the emission of air pollutants. The Air Pollution Control Ordinance (Cap. 311) sets out AQOs and provides for the periodic review of the AQOs at least once every five years with a view to promoting the conservation and best use of air in the public interest. 151

24 The following are criteria of seven types of pollutants included in current AQO of Hong Kong: Concentration Limit [i] (μg/m 3 ) Air Pollutants Averaging Time (Number of Exceedances Allowed) Impacts on health when in high concentration 10mins 1hour 8hours 24hours 1year Sulphur dioxide 500 (3) 125 (3) It can cause respiratory disease, lung function decline, and with air pollutants concentration arises, morbidity and mortality of these diseases will be increased. Respirable suspended particulates (PM10) [ii] 100 (9) 50 (N/A) Its respirable part is injurious to health when inhaled. Fine suspended particulates (PM2.5) [iii] Nitrogen dioxide 75 (9) 35 (N/A) 200 (18) 40 (N/A) It can cause respiratory disease, lung function decline, cancer risk for certain particles, and with air pollutants concentration arises, morbidity and mortality of these diseases will be increased. It can cause respiratory discomfort, being susceptible to respiratory disease, and it can hamper the growth of the lung. Ozone 160 (9) It can cause eye irritation, coughing, exercise capacity recession, and it may damage chromosomes. Carbon monoxide 30,000 (0) 10,000 (0) It can impede functional coordination, health effect in pregnant women and those with heart and circulatory diseases. Lead 0.5 (N/A) It may affect cell and body functions, lead to neuropsychological problem (particularly serious in children). Also it may increase morbidity of heart disease, stroke and hypertension. 152

25 Note: [i] All measurements of the concentration of gaseous air pollutants, i.e., sulphur dioxide, nitrogen dioxide, ozone and carbon monoxide, are to be adjusted to a reference temperature of 293Kelvin and a reference pressure of kilopascal. [ii] "Respirable suspended particulates" means suspended particles in air with a nominal aerodynamic diameter of 10 μm or less. [iii] "Fine suspended particulates" means suspended particles in air with a nominal aerodynamic diameter of 2.5 μm or less. Sources: Environmental Protection Department (2013): Hong Kong s Air Quality Objectives, Retrieved from 153

26 Air Quality Health Index To provide more timely and useful air pollution information to the public, the Environmental Protection Department (EPD) launched the Air Quality Health Index (AQHI) to replace the Air Pollution Index (API) from 30 December What is Air Quality Health Index (AQHI)? The AQHI informs people about the short-term risk of air pollution to help people take precautionary measures to protect their health. How is the Air Quality Health Index calculated and reported? AQHIs are calculated based on the cumulative health risk attributable to the 3-hour moving average concentrations of four air pollutants, including ozone (O 3 ), nitrogen dioxide (NO 2 ), sulphur dioxide (SO 2 ) and particulate matter (PM2.5 / PM10). The risk factors of each pollutant were obtained from local health studies. The AQHIs are reported on a scale of 1 to 10 and 10+ and are grouped into five health risk categories: low (1-3), moderate (4-6), high (7), very high (8-10) and serious (10+). How is the Air Quality Health Index reported? The AQHIs are reported hourly at each ambient ( General AQHI ) and roadside ( Roadside AQHI ) station. The Environmental Protection Department also provide AQHI forecast which serves to alert citizens before the onset of serious air pollution. Relevant health advice is also provided, especially for susceptible groups such as children, elderlies and those with heart or respiratory illnesses. Source: Environmental Protection Department (2013), About AQHI. Retrieved from 154

27 Location of current air quality monitoring stations shows below: Teaching tips Teachers may refer to the real-time air quality as indicated in the website of Air Quality Health Index ( gov.hk/en.html), and guide students to analyse and discuss the real-time air quality in class. Source of photo: Environmental Protection Department(2013): Air Quality Health Index 155

28 Let's think If Hong Kong sets up a stricter Air Quality Health Index, who would be benefitted? Who will thus have to pay for the price of fulfilling it? Reference materials: World Health Organization (2006), Air quality guidelines - global update Retrieved from World Health Organization (2011), Urban Air Pollution Database. Retrieved from Legislative Council ( ), LCQ20: Air quality in Hong Kong, Retrieved from Hong Kong Government Information Services ( ), The New Air Quality Objectives will be Implemented in 2014, Retrieved from Environmental Protection Department (2005), Questions and Answers on the Air Pollution Index and Forecast System, Retrieved from Environmental Protection Department (2009), Review of Air Quality Objectives and Development of a Long Term Air Quality Strategy for Hong Kong - Feasibility Study Final Report. Retrieved from Environmental Protection Department(2013): About Air Quality Health Index. Retrieved from Environmental Protection Department(2013): Hong Kong Air Quality Objectives. Retrieved from 156

29 Station 4: Learning activity 'Survey of public opinions on Hong Kong air quality' Background: Air quality has a significant impact on Hong Kong citizens health and quality of life. In this activity, students have to design their own questionnaires to survey public opinions on current air quality and report their findings. Through analysis and exchange of ideas, they will understand more about air pollution in Hong Kong. Purpose: This activity aims to help students to know more about comments on local air quality through conducting survey, and to enhance their collaboration and study skills. Procedure: Section 1: Questionnaire design 5 minutes: Divide students into 6 groups (6-8 students each group), and distribute Worksheet (1). 20 minutes: Students set the investigation purpose and design the related questionnaire according to Worksheet (1). 15 minutes: Invite 2-3 group representative to share their questionnaire. After that, teachers can introduce to students the skill of designing questionnaires using their designed questions as examples. Students conduct their own survey. Section 2: Report findings and respond to each other 5 minutes: Distribute Worksheet (2) and invite students to divide into 6 groups (6-8 students each group). 30 minutes: Each group then pairs with another to work on Worksheet (2). The procedure is as follows: The first group reports 10 minutes; The second group responds 5 minutes; The second group reports 10 minutes; The first group responds 5 minutes. 30 minutes: Teachers give comprehensive explanation. 157

30 Learning activity: Survey of public opinions on Hong Kong air quality Worksheet (1) Name: Class (No.): ( ) 1. Name of group: 2. Our group decided to conduct a survey on local residents in the following district to understand their views on regional air quality: Reasons of selecting this district: Term explanation Open-ended Question and Close-ended Question Open-ended question and close-ended question are two main ways of designing questionnaire or interview questions for social investigation. Open-ended question requires respondents to suggest answers using their own words. For example, "What factors do you think would affect the air quality 3. Design a questionnaire consisting of at least 8 close-ended questions and 2 open-ended questions. on campus?" Close-ended question provides respondents with a list of answer choices for them to choose. For example, when we ask Which of following factors do you think would affect the air quality on campus?, we will offer respondents some options to choose. Topic of questionnaire: Reference: Rubin, Allen (2007), Essential Research Methods for Social Work. Belmont: Thomson/Brooks/Cole. Purpose of survey: 158

31 Design questions Close-ended questions: Q1: Q2: Q3: Q4: Q5: Q6: Q7: Q8: Open-ended questions: Q1: Q2: 4. Students gather public opinions of at least 20 citizens in the district. 5. Students analyse the collected data and information and prepare to report the results in class. 159

32 Learning activity: Survey of public opinions on Hong Kong air quality Worksheet (2) Name: Class (No.): ( ) Pay attention to the content of other groups reports, and respond according to the following five aspects: Purpose of survey e.g.: whether the air pollution in school or in the community can be acknowledged; whether the sources of these problems can be identified. Design of questions e.g.: whether the designed questions are clear and concise; whether the designed questions allow respondents to provide accurate and adequate answers. 160

33 Data and information analysis e.g.: whether the analysis is accurate; whether sufficient arguments from information are listed and the problems and their reasons are summarised. Report method e.g.: whether the expression is clear and concise; whether the information and analysis are structured. Others e.g.: cooperation between group members. 161

34 Station 5: Overview on Hong Kong s air pollution, its impacts and coping strategies Background information (3) Overview on Hong Kong s air pollution Hong Kong s air pollution mainly comes from six kinds of pollutants, including nitrogen dioxide (NO 2 ), respirable suspended particulates (RSP), sulphur dioxide (SO 2 ), volatile organic compounds, carbon monoxide (CO) and ozone (O 3 ). The main sources of these pollutants include electricity generation, road transport, water transport, civil aviation, other combustion sources and non-combustion sources. The diagram below shows data of nitrogen dioxide, respirable suspended particulates and ozone concentration acquired from all district monitoring stations in Hong Kong in 2010, reflecting the status of air pollution in Hong Kong. Concentration (micrograms/cubic meter) Central and Western District Eastern District Kwai Chung Kwun Tong Maximum 1-hour Average Monitoring Result of Nitrogen Dioxide in 2010 Sham Shui Po Tsuen Wan Sha Tin Tai Po Tung Chung Yuen Long Grass-Island (Tap Mun) Causeway Bay Central Mong Kok The World Health Organization pointed out that experiments on animal and humans have shown that short-term exposure to nitrogen dioxide with concentrations exceeding 200 micrograms/cubic meter have significant impacts on health. Studies on bronchial reactivity have shown that nitrogen dioxide with concentrations higher than 200 micrograms/cubic meter will increase asthma patients bronchial reactivity. Exposure to nitrogen dioxide with concentrations exceeding 500 micrograms/cubic meter will cause acute health effects. The latest air quality guidelines announced by the World Health Organization in 2006: Average concentration of nitrogen dioxide (per hour) is 200 micrograms/cubic meter Annual Average Minimum 1-hour Average 162

35 140 Monitoring Result of Nitrogen Dioxide in 2010 (annual average) The latest air quality guidelines announced by the World Health Organization in 2006: Concentration (micrograms/cubic meter) Annual average concentration of nitrogen dioxide is 40 micrograms/cubic meter 0 Central and Western District Eastern District Kwai Chung Kwun Tong Sham Shui Po Tsuen Wan Sha Tin Tai Po Tung Chung Yuen Long Grass-Island (Tap Mun) Causeway Bay Central Mong Kok 163

36 450 Monitoring Result of Ozone in Monitoring Result of Respirable Suspended Particulates in 2010 (annual average) 400 Concentration (micrograms/cubic meter) Concentration (micrograms/cubic meter) Central and Western District Eastern District Kwai Chung Maximum 1-hour Average Kwun Tong Sham Shui Po Tsuen Wan Sha Tin Tai Po Tung Chung Yuen Long Grass-Island (Tap Mun) 0 Central and Western District Eastern District Kwai Chung Kwun Tong Sham Shui Po Tsuen Wan Sha Tin Tai Po Tung Chung Yuen Long Grass-Island (Tap Mun) Causeway Bay Central Mong Kok Annual Average The World Health Organization pointed out that exposure to ozone with an 8-hour average concentration higher than 160 micrograms/ cubic meter exceeding 6.6 hours may cause physiological damage and inflammatory lung injuries to healthy young people with regular exercises. The latest air quality guidelines announced by the World Health Organization in 2006: 8-hour average concentration of ozone is 100 micrograms/cubic meter The World Health Organization pointed out that longterm exposure to PM10 with an average concentration of 50 micrograms/cubic meter will increase the risk of death by about 9%. The latest air quality guidelines announced by the World Health Organization in 2006: Average concentration of PM10 is 20 micrograms/cubic meter Source: Environmental Protection Department (2011), Air Quality in Hong Kong Retrieved from 164

37 Teaching tips In order to enhance students motivation to learn, teachers may play the following video and guide students to think about what kind of air pollution has been caused by our daily life. In addition, teachers can explain the conflict between social needs and environmental protection through the example of resistances faced by the proposed policy of emission reduction shown in the film. RTHK LegCo Review, the eleventh episode: Political Consideration Makes Air Pollution Difficult to Improve. (Hours: 00:38 to 05:01) ( 165

38 Causes of air pollution in Hong Kong Emissions from electricity generation and transportation Vessel 年 平 emissions, 均 濃 度 為 vehicle 40 微 克 exhaust / 立 方 and 米 1 power 小 時 plant 平 均 emissions 濃 度 為 200 of dust, 微 克 particulates / 立 方 米 and nitrogen oxides are the main sources of air pollution in Hong Kong. Emissions of diesel vehicles, such as trucks, buses and minibuses, are the main sources of roadside air pollution. Regional smog is caused by a combination of pollutants from vehicles, factories and power plants both in Hong Kong and the Pearl River Delta region. Hong Kong has numerous hills and few flatlands, accompanied with poor urban planning leading to intensive buildings and narrow roads. With the massive influx of immigrants in recent decades and economic development, Hong Kong has become a big city inhabited by 7 million people. Large amount of people and vehicles are trapped in limited space in between adjoining buildings, making air pollution even worse. Hong Kong s geographical factors exacerbate pollution problem The insufficient distances between buildings, and buildings which are arranged densely at riversides and coast lines by property developers, block the airflow. "Street canyon" is also commonly seen in districts like Central, Wan Chai, Yau Ma Tei, Mong Kok, Tai Kok Tsui, Kowloon West, Tseung Kwan O, etc. The data from the HKUST Air Monitoring Platform (MAP) has proved that air circulation is beneficial to evacuating air pollutants. Even if the distance between regions with good and poor ventilation is only tens of meters, Air Pollution Index of the two places would have a large difference. (Civic Exchange, 2010) Poorly ventilated environment in Hong Kong makes air pollutants unable to be evacuated, which further deteriorates air pollution. Impacts of pollution in Mainland Power plants and automobile factories in Southern China mostly use coal and diesel as energy source, emitting large quantities of sulphur dioxide, nitrogen dioxide and particulates. When these pollutants are blown from the North to the Pearl River Estuary, air quality in Hong Kong would be affected. According to the report Relative Significance of Local vs Regional Sources: Hong Kong s Air Pollution, published by the Institute for the Environment of HKUST and Civic Exchange, pollution sources from the Pearl River Delta Economic Zone accounted for approximately 60% of the annual pollution level in the HKSAR in 2007, and this percentage would rise to 70% in winter. (Institute for the Environment of HKUST and Civic Exchange, 2007) 166

39 Case study: Understanding the differences between General and Roadside Air Quality General Air Quality General air quality monitoring stations are located on rooftop about 3-6 storeys above ground level in open space. Result derived from the station can reflect the air pollution level which most local people are exposed to for a long time. Since most people generally stay away from the roadside for most of time, the general air quality is more relevant to them. Roadside Air Quality Unlike general air quality monitoring stations, the three roadside air quality monitoring stations locate in Central, Causeway Bay and Mong Kok at ground level next to a busy road, surrounded by high-rise buildings which hinder air circulation, making vehicle emissions unable to be effectively dispersed and diluted, Roadside air pollution level recorded is higher than that of the general air quality monitoring stations. But the air quality of these roadside air quality monitoring stations can only reflect the condition of roadside air pollution, surrounded by heavy traffic and high-rise buildings, which have a greater significance for those who spend most of their daily activities on the roadside. Residents in Mong Kok can refer to the data of the Sham Shui Po general air quality monitoring station, while residents in Central and Causeway Bay can refer to the data of the Central/ Western general air quality monitoring station, both of which are the respective neighbouring districts, rather than the data of roadside monitoring station. 167

40 Impacts of air pollution in Hong Kong Damage to health Air pollution affects our health seriously, making those exposed to polluted air in long-term especially children, elderlies and patients suffer from illness. According to a study of the Department of Paediatrics and Adolescent Medicine of The University of Hong Kong from 1995 to 2002, the level of air pollutants in Hong Kong is proportional to hospital admissions of children with asthma. Pollutants, such as nitrogen dioxide, ozone, PM10 and PM2.5, etc., may increase the hospitalisation rate of children with asthma. The study also demonstrated the correlation between PM2.5 and asthma for the first time in scientific researches. The study pointed out that if the average concentration of air pollutants was lowered by about 50%, the number of hospitalised children would be reduced by (Liu Yulong and Li Sulun, 2006) Exacerbation of climate change Carbon dioxide and methane are major greenhouse gases. Continuous emission of these pollutants has also exacerbated the problem of greenhouse gas emissions. In 2008, Hong Kong s total greenhouse gas emissions have reached 42 million tons. Power generation, energy combustion and transportation are the main sources of greenhouse gas emissions in Hong Kong. As the largest source of emissions, electricity generation accounts for about 67% of carbon emissions in Hong Kong in 2008, while transportation is the second largest source of emissions, accounting Impacts on international competitiveness of Hong Kong Impacts on visibility Vehicle emissions of nitrogen oxide and volatile organic compounds, volatile organic compounds produced in our daily life and so on will have chemical reaction under sunlight and form ozone. (Botkin & Keller, 2011) Ozone and particulates in the air may form smog, reducing visibility. According to the 2009 Air Quality Objectives Review by the Environmental Protection Department, ozone concentration in Hong Kong had risen from about 20 micrograms/cubic meter to more than 30 micrograms/cubic meter from 1990 to (Environmental Protection Department, 2009) With the economic development of the Pearl River Delta region, the accumulation of pollutants is becoming more severe, exacerbating the problem of regional smog. Air pollution also affects the economic development of Hong Kong. According to ECA International s annual survey of city ranking, Hong Kong failed to achieve a higher ranking due to air pollution. This reflects that life quality in Hong Kong was damaged by air pollution, which reduced the city s attractiveness to foreign enterprises and talents. (ECA International, 2012) According to the survey on Hong Kong environmental quality, conducted by American Chamber of Commerce in 2007, 70% of respondents knew that some experts refused to work in Hong Kong because of air pollution. 78% of respondents felt that Hong Kong s attractiveness to foreign investors was reducing. 57% of respondents even noted that the continuing air pollution problem would eventually cause their companies to invest elsewhere. This shows that Hong Kong s air pollution has become a major obstacle in attracting foreign investments and recruiting international talents. (American Chamber of Commerce, 2007) 168