Proven/peer-reviewed medical evidence that directly link environmental exposure to direct health effects (land)

Procedia - Social and Behavioral Sciences 153 ( 2014 ) 221 – 229

Available online at www.sciencedirect.com

ScienceDirect

1877-0428 © 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the Association of Malaysian Environment-Behavior Researchers, AMER (ABRA malaysia). doi: 10.1016/j.sbspro.2014.10.056

AicQoL2014Kota Kinabalu AMER International Conference on Quality of Life

The Pacific Sutera Hotel, Sutera Harbour, Kota Kinabalu, Sabah, Malaysia 4-5 January 2014

“Quality of Life in the Built & Natural Environment”

Human Health and Wellbeing: Human health effect of air pollution

Nurul Ashikin Bte Mabahwi*, Oliver Ling Hoon Leh, Dasimah Omar Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, 40450 Shah Alam, Malaysia

Abstract

Air pollution can harm human health, the environment, and cause property damage. Various research have proven the connection of air quality and human health. The epidemiology and laboratory studies demonstrated that ambient air pollutants (for example PM, O3, SO2 and NO2) contributed to various respiratory problems including bronchitis, emphysema and asthma. The objective of this paper is to discuss the relationship between the human health and air quality. This conceptual paper is focussing on the findings from air quality literature review and the significant health effects related to it. © 2014 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the Association of Malaysian Environment-Behaviour Researchers, AMER (ABRA Malaysia).

Keywords: Air pollution; health effects; respiratory; particulate matter

1. Introduction

Clean air is what all living humans and animals needs for good health and well-being. However, due to unstoppable urban development, the air is continuously polluted. Urban ambient air is more polluted than overall atmosphere, due to high density of human population and their activities in urban areas; it produces air pollutants with a higher rate as compared to less-developed areas and natural environment (Ling et al. 2012). As for the example, urban conurbation like Klang Valley with high volume of traffic

* Corresponding author. Tel.: +6019-6061783 E-mail address: [email protected].

© 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/). Peer-review under responsibility of the Association of Malaysian Environment-Behavior Researchers, AMER (ABRA malaysia).

222 Nurul Ashikin Bte Mabahwi et al. / Procedia - Social and Behavioral Sciences 153 ( 2014 ) 221 – 229

and high density of developments contribute to the decrease of urban air quality. In referring to Malaysian cases, clear increasing trend in the number of unhealthy or hazardous days which increased from 11 days in 2001 to 67 days in 2005 at Kuala Lumpur (Ling et al, 2010). Other than that, in August 2012, air quality monitoring at Port Klang, Selangor showed the worst (unhealthy) Air Pollution Index of 118 due to the influenced of monsoon wind from Sumatera (JAS, 2012). Not just Klang Valley, but most cities in developing countries are facing increasing environmental pollution from vehicle emissions, and from industries and domestic heating sources at a level that exceeds the capacity to disperse and dilute emissions to non-harmful exposure levels (UN, 2001). The World Health Organization (WHO) stated that urban air pollution as a critical public health problem, and more than 2 million premature deaths each year can be attributed to the effects of urban outdoor air pollutant and indoor air pollutant (WHO, 2006). However, the consequences of air pollution on public health are measured not only in terms of sickness and death, but also in terms of lost productivity and missed educational and other human development opportunities (UN, 2001). The adverse health effects, such as respiratory morbidity, cardiovascular diseases and mortality, have created a public awareness to the urban air pollution. Evaluations and assessments on health have become more important since they serve as a basis to carry out a re- formulation or review on the current air quality standards (Colls & Micallef, 1997). The Clean Air Act of 1970 regarded pollutants, such as sulphur dioxide, carbon monoxide, particulates, volatile hydrocarbons, photochemical oxidants, and lead, to be the greatest threats to human health (Cunnningham et al, 2005). No doubt, these pollutants have the capabilities to threat the human health and environment, and could cause significant damages to properties. As stated by numerous scholars, particle pollution and ground level ozone are at the pinnacle among six other pollutants as the most threatening factors to the human health. The epidemiology and laboratory studies also demonstrated that ambient air pollutants (for example, PM, O3, SO2 and NO2) contributed to various respiratory problems including bronchitis, emphysema and asthma (Ling et al, 2012). While in Malaysia, Health Facts 2012 by Ministry of Health Malaysia (MoH) stated that, in 2011, diseases of the respiratory system are one of the principal causes of hospitalization in MoH hospital with the percentage of 10.36% (MoH, 2012). Surprisingly, one of the principal causes of death at MoH hospital in 2011 was also diseases of the respiratory system with percentage of 19.48% (MoH, 2012).

2. Environmental health

Environmental health has a very strong connection between the human health and healthy environment and it’s often due to an imbalance resulting from poor adjustment between the individual and the environment (Botkin & Keller, 2007). It focuses on the external factors that cause disease, including elements of the natural, social, cultural, and technological worlds in which we live (Cunnigham & Saigo, 2005). A disease is an abnormal change in the body’s condition that impairs with physical or psychological functions (Cunningham and Saigo, 2005). According to Ahluwalia and Malhotra (2008), air, water and soil represent the environment as a whole. There are two types of environment: natural and man-made. Natural environment composes of everything that affects an organism during the course of its lifetime, such as air, water, soil, radiation, land, forest, wildlife, flora and fauna etc. From a human perspective, environmental issues involve concerns regarding science, nature, health, employment, profits, politics, ethics and economics (Enger & Smith, 2000). Most social and political decisions are usually made with respect to the political jurisdictions. Environmental problems are not necessarily bound to these artificial, political worlds. Air pollution may simply involve from as low as governmental units to as serious as international states (Enger & Smith, 2000).

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The environment comprises of four segments: atmosphere, hydrosphere, lithosphere and biosphere. The planetary layer of gases enveloping the Earth is held in its place by gravity (Kemp, 2004). This is the atmosphere, and it is responsible for sustaining life by protecting the planet and its inhabitants from the detrimental ultraviolet rays from the Sun. It also contains life-supporting gases such as oxygen and carbon dioxide for its inhabitants [Ahluwalia & Malhotra, 2008). Ozone is a dangerous pollutant, in the ambient air, but it operates as a protective shield from the ultraviolent radiation rays by the stratosphere. (Cunningham et al, 2005).

3. Air

The atmosphere, or air, is normally composed of 79-percent nitrogen, 20-percent oxygen, and one percent mixture of carbon dioxide, water vapour, and small quantities of several other gases. Most of the atmosphere is held close to the Earth by the gravitational pull. Therefore, the composition of its closest point to the surface of the Earth is thinner (Enger & Smith, 2000). The atmosphere consists of the troposphere, a relatively dense layer of gases closest to the surface of the Earth; stratosphere, more distant with similar but less dense gases, and the ionosphere, composed of ionized gases (Enger & Smith, 2000). Just as it contains gaseous components, the atmosphere also holds non-gaseous materials present in the form of solid or liquid particles dispersed into the air, such as aerosols or particulate matter (Kemp, 2004), refer to figure 1.

Fig 1. Sources of aerosols and particulate matter in the environment Source: Kemp, (2004)

Kemp (2004) also stated that, they are often regarded as synonymous with air pollution, although the elements involved like dust, soot, smoke, and salt particles are regularly produced by natural processes such as volcanic activity, forest or grass fires, evaporation and air movement, while normal biological processes create and release spores, pollen grains, bacteria, viruses and a variety of other microscopic particles. The atmosphere is very important because, the atmosphere performs several functions that have allowed humans to survive and develop almost anywhere in the earth’s surface (Kemp, 2004). As listed below is the functions atmosphere that highly connected with air:

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Atmosphere provides and maintains the supply of oxygen required for life itself. Controls the earth’s energy budget through such elements as the ozone layer and the greenhouse effect

and its internal circulation, distributes heat and moisture across the earth’s surface. Atmosphere has the capacity dispose of waste material or pollutants generated by natural or human

activity. As mentioned above, the atmosphere consists of a mix of gases plus liquid and solid particles in

proportions that vary in both time and places, but when the atmosphere is unable to rid itself of the material being added to it, the build-up of gases and aerosols causes it to become polluted (Kemp, 2004), and this pollution is called as air pollution.

4. Air pollution

Pollution, an unwanted destruction of the natural environment by human and naturally induced insults, is a problem facing the present world Wiwanitkit (2011). Due to the expansion of the world population, the number of people is rapidly growing. It is accepted that pollution is a problem, not for a specific group but for everyone. The environmental pollution includes air, water and land (or soil) pollution. Enger & Smith (2000) stated that pollution as something that people produce in large enough quantities that it interferes with our health or well-being. The contributing factors toward pollution are the size of a population and the development of technology that paves into the methods utilized to develop pollution (Enger & Smith, 2000). In a more practical sense, pollution is a product from the inefficiency of human- developed processes. Raw materials extraction, product manufacturing, power necessary for the processes in manufacturing and the products have inherent inefficiencies leading to a considerable amount of waste (pollution) that is no longer of use (Wagner, 1994). Air pollution is physical or chemical changes brought about by natural processes or human activities that result in air quality degradation (Cunnigham et al, 2005). The release of large amounts of smoke and other forms of waste into the air caused an unhealthy condition because the pollutants were released faster than they could be absorbed and dispersed by the atmosphere (Enger & Smith, 2000).

In referring to history, people have long recognized the existence of atmospheric pollutants, both natural and human induced (Botkin & Keller, 2007); Leonardo da Vinci wrote in 1550 that a blue haze formed from materials emitted into the atmosphere from trees. The air pollution is classified into three following types which are the Natural Pollutants, Primary Pollutants and Secondary Pollutants. Natural Pollutants are natural phenomena of pollutants that find their way into the atmosphere. Some examples of the natural pollutants are forest fires started by lightning or ddispersal of pollen. This paper will focus to primary pollutants and its affect. Five major types of materials that released directly into the atmosphere in their unmodified forms and in sufficient quantities to pose a health risk are carbon monoxide, hydrocarbons, particulates, sulphur dioxide, and nitrogen compounds (Enger & Smith, 2000). These materials can interacts with one another in the presence of an energy source to form new secondary air pollutants such as ozone, very reactive materials and natural chemicals in the atmosphere. Sources of primary air pollutants as listed in Table 1. Table 1. Sources of primary air pollutants

Pollutant Sources

Carbon monoxide Incomplete burning of fossil fuels

Tobacco smoke

Hydrocarbons Incomplete burning of fossil fuels

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Tobacco burning

Chemicals

Particulates Burning fossil fuels

Farming operations

Construction operations

Industrial wastes

Building demolition

Sulphur dioxide Burning fossil fuels

Smelting ore

Nitrogen compounds Burning fossil fuels

Source: Enger & Smith (2000)

5. Health effects of air pollution

Though we have exploited our incredible ability to manipulate the environment, we are beginning to realize that every impact we bring upon the environment also has an impact on us. The analogy of environment and pollution given by Wagner in 1994 was Earth can be compared to a fish bowl. That is, the Earth, like a fish bowl, is a contained environment; what goes in stays in. Pollutants that are emitted or discharged do not disappear, but will remain to impact us. Due to the unstoppable urbanisation in this world and Malaysia especially, risk of getting affected by pollution is high. More than 2 million premature deaths each year can be attributed to the effects of urban outdoor air pollution and indoor air pollution (caused by the burning of solid fuels). More than half of this disease burden is borne by the populations of developing countries (WHO, 2006). Heart attacks, respiratory diseases, and lung cancer are all significantly higher in people who breathe dirty air compared to matching groups in cleaner environments (Cunningham, et al 2005). Hundreds of deaths have been directly related to poor air quality in cities. There was a case of air pollution that was harmful to human health occurred in Donora, Pennsylvania in October 1948. Air pollution in that area came from pollutants from a zinc plant and steel mills became trapped in the valley, and dense smog formed. Within five days, seventeen people died and 5910 persons became ill. The polluted atmosphere affected nearly 50 percent of the city’s 12,300 in habitants (Enger & Smith, 2000).

Surprisingly, study published in the Lancet Respiratory Medicine shows that air pollution during pregnancy may increase the risk of lower birth weight babies, even at lower air pollution level acceptable by the current European Union air-quality directives. Based from data by the European Study of Cohorts for Air Pollution Effects (ESCAPE), 14 cohort studies from 12 European countries, involving 74,000 women who had singleton babies between 1994 and 2011 were analysed. The findings showed that all air pollutants, particularly fine particulate matter (PM2.5 with a diameter of 2.5 micrometres or less), and traffic density reduced the average head circumference of a child at birth and increased risk of low birth weight at term. In the study population, average pollution exposure levels ranged from less than 10 micrograms per cubic meter (10μg/m³) to almost 30μg/m³. The researchers estimate that for every increase of 5μg/m³ in exposure to PM2.5 throughout pregnancy, the risk of low birth weight at term increases by 18% (Lancet, 2013). In referring to Enger & Smith (2000), several hours of exposure to air containing 0.001 percent of carbon monoxide can cause death. This is because CO remains attached to haemoglobin for a long time even with small amounts it tends to accumulate and reduce the blood’s oxygen-carrying capacity. In addition, carbon monoxide produced in heavy traffic can cause headaches, drowsiness and blurred vision. Other than that, a heavy smoker in congested traffic is doubly exposed and

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may experience severely impaired reaction time compared to non-smoking drivers. Respirable particles that smaller than 2.5 micrometres are among the most dangerous of particulates matter because they can be drawn into the lungs, where they damage respiratory tissues. Asbestos fibers and cigarette smoke are categorized among the most dangerous respirable particles in urban and indoor air because they are carcinogenic (Cunningham et al, 2005). The danger is because carcinogen is a substance that can cause cancer.

Fig 2. Parts of the human body Source: Botkin & Keller, (2007)

Figure 2 shows some of the part of the human body (brain, cardiovascular system, and pulmonary system) that can be damaged by common air pollutants. The most severe health risks from normal exposures are related to particulates. People who suffering from respiratory diseases are the most likely to be affected by air pollutions (Botkin & Keller, 2007). In addition, not just air pollution can cause health effects, study also shows that air pollution can cause stress to a human being. Study by Sahari et al (2012), stated that environment can affect stress in human beings. Good and healthy environment can cause positive impacts to people as well as unhealthy environment can cause problems and eventually stress. The study shows that bad atmosphere condition (air & temperature) surrounding the living areas and living space which is near to pollution as among the factors of human stress.

Table 2. The types of health effects experienced by the most common pollutants at elevated levels:

Pollutant Description Health effects

Ozone Colourless gas with slightly

sweet odor

These gases irritate the airways of the lungs, increasing the symptoms of

those suffering from lung diseases, strong irritant, aggravates asthma, causes

injury to cells in the respiratory system, coughing, chest discomfort, eye

irritation

Particulate

matter

Very small particles Fine particles can be carried deep into the lungs where they can cause

inflammation and a worsening of heart and lung diseases

Carbon

monoxide

Colourless, odourless gas This gas prevents the uptake of oxygen by the blood. This can lead to a

significant reduction in the supply of oxygen to the heart, particularly in

people suffering from heart disease. Causes headache, fatigue, nausea

Nitrogen Most are colourless and Non-irritating gas may aggravate respiratory infections and symptoms (sore

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oxide odourless, NO2 with particles is

reddish-brown

throat, cough, nasal congestion, and fever), increase the risk of chest cold,

bronchitis, and pneumonia in children.

Sulphur

dioxide

Colourless, odourless gas Increase in chronic respiratory disease, shortness of breath, narrowing of

airways for people with asthma

Lead Heavy metal Children most at risk; brain damage, behaviour problems, nerve disorders,

digestive problems

Source: Adapted from Defra (2013) and Botkin & Keller (2007)

NRDC (2005), listed air pollutants of ground level ozone, sulfur dioxide, particulate matter and nitrogen oxide as the main factors contributing to asthma. Ozon will occur at ground level when pollution from vehicles reacts with oxygen and sunlight. Not just ozone will lead to the development of asthma in children but it will also makes existing asthma worse. Sulfur dioxide is recognized as a respiratory irritant associated with the onset of asthma attack. Particulate matter are the finest air pollutant synonyms with tiny particles in the air with the shape of dust, soot, fly, ash, wood smoke, sulfate aerosols and diesel exhaust particles. These fine particles can become lodge in the lungs and could trigger asthma attacks. Studies shown the number of hospitalizations for asthma increases when levels of particulate matter in the air rise. Other than that, nitrogen oxide can reacts with other air pollutants and form small particles that can cause breathing difficulties especially in people with asthma.

6. The most widespread air pollutants

Fig 3. (a) Air pollution remains a major danger to the health of children and adults Source: American Lung Association (2013)

American Lung Association (2013) empasized that ozone and particle pollution are the most widespread air pollutants and the most dangerous. This is because particulate matter or particle pollution is a mix of very tiny solid and liquid particles in the air we breathe daily and it can shorten our life. The tiny size of the particles make it widespread and everywhere, we cannot even see it, and some are tinier and can only be seen with an electron microscope. Particles that are smaller than 10 micrometers in diameter or about 1/7 the diameter of a single human hair will get trapped in the lungs while the smallest can pass through lungs into the blood stream. Figure below shos the comparison size of particulate matter

(b) Size of particulate matter Source: American Lung Association (2013)

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and single human hair. As listed by the American Lung Association (2013), people that are at risk of particulate matter are infants, children and teens, people over 65 years old, people with lung disease (asthma, chronic pulmonary disease, chronic bronchitis and emphysema), people with heart disease or diabetes and people who work and active outdoors. For diabetic people the risk is higher because exposure to particulate pollution will lead to cardiovascular disease. Short term exposure to particle pollution will lead to following health effects: death from respiratory and cardiovascular causes, including strokes; increased mortality in infants and young children; increased numbers of heart attacks, especially among the elderly and in people with heart conditions; inflammation of lung tissue in young, healthy adults; increased hospitalization for cardiovascular disease, including strokes and congestive heart failure; increased emergency room visits for patients suffering from acute respiratory ailments; increased hospitalization for asthma among children; increased severity of asthma attacks in children.

Despite the above deadly affect, breathing daily in particulate pollution (year round exposure) can lead to the following health effects: increased hospitalization for asthma attacks for children living near roads with heavy truck or trailer

traffic; slowed lung function growth in children and teenagers; significant damage to the small airways of the lungs; increased risk of dying from lung cancer; increased risk of death from cardiovascular disease; increased risk of lower birth weight and infant mortality

US EPA (2009), conclude that fine particle pollution lead to serious health threats. It can causes early death (both short-term and long-term exposure), causes cardiovascular harm such as heart attack, strokes, heart disease, congestive heart failure. Particle pollution likely to cause respiratory harm that will make the asthma, COPD and inflammation getting worse. This deadly air pollutant may cause cancer and may cause reproductive and developmental harm.

7. Conclusion and recommendation

Human must understand the chain of causality in urban environmental health, because the chain of causality in environmental health begins with the impact of human factors (urbanisation) on the environment and human health. Human factors are the driving force to the destruction of environment and air quality especially, such as urban development, traffic, etc. This driving force of human activities will result in the effects of human health. In conclusion, human are responsible with the waste emitted to the air and society must take necessary actions to overcome the air pollution matter. Air pollution not just will harm human health but also other aspects of the environment such as visual qualities, vegetation, animals, soils and water quality.

Acknowledgements

The authors would like to thank Research Management Institute (RMI), Universiti Teknologi MARA (UiTM) for funding the study by given the RIF grant with the project code 600-RMI/DANA 5/3/RIF (204/2012).

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