Browsed by
Month: February 2022

Lullabies of a City

Lullabies of a City

Comments 0 Comment

Close your eyes and take in the sounds around you. Perhaps you notice the whirling of the fans or air conditioning around you, or the minute ticking of your desk clock. Most likely though, you will hear the ever faint sounds of vehicles zipping down the streets, or the very distant sounds of construction. Although most of us would have been conditioned to subconsciously tune these noises out, they indadvertedly still stimulate the nervous systems in our bodies, and in a city where such noises are

Noise pollution impact millions on the daily basis, resulting in common illnesses such as noise induced hearing loss, increased blood pressure as well as psychological impacts such as increased stress and irritation (Stansfeld & Matheson, 2003). It has been found that children who grew up near airports developed poor memory as well as low levels of attention (Hart, 2018). Noise pollution also affect adults through poor quality of sleep, which affects productivity and overall health and mentality of a person. Several serious cases might even result in tinnitus or paracusis.

According to local guidelines on permissible noise, Singapore’s Environmental Protection and Management Act (EPMA) states that residential noise should not exceed 65 decibels in the day, and 55 decibels during the night. The video below demonstrates what each decibel would sound like, and if you would like to know whether your current environment is within stipulated guidelines, online noise meter apps such as this can help.

http://www.youtube.com/watch?v=1XUovxiTpVA

Now that we know about the sources and consequences of noise pollution, perhaps it is wise to turn down the volume of your headphones, and be more aware of the items around your house that causes tiny ticking sounds. In the next blog post, we will cover some of the ways cities take action in combatting noise pollution.

References

Hart, J. (2018). Noise Pollution is Hurting Our Health. Alternative and Complementary Therapies, 24 (5), 229–231. https://doi.org/10.1089/act.2018.29185.jha

Stansfeld, S. A., & Matheson, M. P. (2003). Noise Pollution: Non-Auditory Effects on Health. British Medical Bulletin, 68 (1), 243–257. https://doi.org/10.1093/bmb/ldg033

Urban Revitalisation of Seoul City

Urban Revitalisation of Seoul City

Comments 0 Comment

In the aftermath of the World War II, many Asian countries placed growing their economy as a priority, which resulted in rapid urbanisation and the negligence of quality of life and proper urban planning (Y.-K. Lee et al., 2014). For this blog post, we place focus on the case study of the Cheonggyecheon restoration project, an attempt by Seoul City to veto the horrible air pollution and poor quality of life brought about by poor urban design in the past.

The Cheonggyecheon is an eleven-kilometre stretch of stream that flows through the central part of Seoul, the capital of Korea. The water in the previously ephemeral stream Cheonggyecheon originates from the highlands north of the stream, such as the Bukhan mountain (Jeon & Kang, 2019). Cheonggyecheon then flows and connects to the Han River, which drains out into the Yellow Sea.

Prior to the restoration in 1958, Cheonggyecheon stream was buried under an expressway that was 50m wide and span 6km in length. Later in 1976, an elevated highway was built upon the pre-existing highway to mitigate congestion issues (Kim & Jung, 2019). As majority of the land-use around Cheonggyecheon was roads and traffic, it led to a decline in air quality around the Central Business District (CBD) area of Seoul. A study found that citizens who worked or lived near the area were twice as likely to suffer from respiratory illnesses as compared to other Seoul citizens (Hwang, 2004). This was due to the high nitrous oxide and benzene levels from idling vehicles.

Fig 1: The before and after comparison of downtown Seoul (Source: Seoul City)

Talks of restoring the Cheonggyecheon began with the election of Seoul’s first conservative mayor Lee Myungbak in 2002. Lee’s political campaign focused on improving environmental and cultural spaces in the city to increase the quality of life and revitalise the dull urban environment that resulted from the rapid urbanisation in Seoul. The Cheonggyecheon Project promises to do just that; the removal of the expressways encouraged citizens to switch over to active mob ility methods like walking and cycling (Kim, 2007), greatly improving the air quality due to the large decrease in vehicles passing through the CBD area. In fact, the city saw major decline in records of air pollutants such as carbon monoxide, nitrogen dioxide and ozone prior to and after the restoration project (Hoe, 2006).

The Cheonggyecheon project has become a global example that advocated the importance of green and sustainable spaces in a city. It also presents ideas and encouragement of utilising active mobility and public transport as effective ways to curb vehicle air pollution in cities.

References

Hoe, Y. (2006). The Research Regarding the City Air Environment Improvement Effect Follows in the Cheonggye Stream Restoration (Master’s Thesis). University of Seoul, Seoul, South Korea.

Hwang, K. Y. (2004). Restoring Cheonggyecheon Stream in the Downtown Seoul. http://lloydgoff.com/airparkvillage/beyondoilusa/news/b7-hwang.pdf

Jeon, C., & Kang, Y. (2019). Restoring and Re-Restoring the Cheonggyecheon: Nature, Technology, and History in Seoul, South Korea. Environmental History, emz032. https://doi.org/10.1093/envhis/emz032

Kim, B. (2007). Urban typological analysis of the cheonggye stream restoration project in seoul. The Korea Spatial Planning Review, 53, 110–130. https://doi.org/10.15793/kspr.2007.53..007

Kim, H., & Jung, Y. (2019). Is Cheonggyecheon sustainable? A systematic literature review of a stream restoration in Seoul, South Korea. Sustainable Cities and Society, 45, 59–69. https://doi.org/10.1016/j.scs.2018.11.018

Lee, Y.-K., Lee, C.-K., Choi, J., Yoon, S.-M., & Hart, R. J. (2014). Tourism’s role in urban regeneration: Examining the impact of environmental cues on emotion, satisfaction, loyalty, and support for Seoul’s revitalized Cheonggyecheon stream district. Journal of Sustainable Tourism, 22(5), 726–749. https://doi.org/10.1080/09669582.2013.871018

The Asian Yellow Dust – Part 2

The Asian Yellow Dust – Part 2

Comments 0 Comment

In the previous blog post, I introduced the phenomenon of the Yellow Dust that brings in air pollutants from the arid regions of continental Asia, into the cities of China, Korea and Japan. I also mentioned that the composition of the particles are mainly fine or ultra-fine sand which was the result of aeolian processes and years and years of erosions of the landscape of the deserts. From this, we would think that the causes of the Yellow Dust is inherently natural. However, as with most environmental issues, anthropogenic activities have intensified the impacts of the Yellow Dust.

 

Desertification

Fig 1: Desertification in China, where land exhausted of its water and nutrients from intensive agriculture (source: Science Photo Library)

 

The dust storms that distributes the sediments of the deserts to the entire East Asia are the result of ongoing desertification. Following global warming and climate change, which exacerbates dry spells, desertification has intensified throughout the years. Placing focus on China’s arid regions, we see that the country is expected to lose almost 1 million square kilometres of humid areas to arid and semi-arid regions by 2030 (FAO, ?). Aside from climate change, local anthropogenic activities also contributes significantly to desertification. With rapid increase of the Chinese population comes over-utilisation of China’s land resources; more land cleared to build cities to house more people, intensified agriculture and livestock rearing. Such activities places immense stress on land as well as water resources, resulting in the drying up of groundwater resources, leading to desertification (FAO, ?)

 

Industrial pollutants laced with sand sediments

During recent studies on the Yellow Dust, it was discovered that sand particles from the desert was not the only form of pollutant within the Yellow Dust. Secondary particles such as mercury and cadmium has been detected amongst the pollutants, and its origins can be traced back to the industries of China (Kang & Kim, 2014).

 

Political conflicts

Needless to say, the mitigation and slowing down of desertification, as well as the Chinese industry’s issue of transboundary pollution has brought about political discussions with the affected countries in East Asia, for example setting up a Republic of Korea-China Joint Committee on Environmental Cooperation to discuss cooperative efforts to tackle air pollution (Kang & Kim, 2014).

 

References

Kang, D., & Kim, J.-E. (2014). Fine, ultrafine, and yellow dust: Emerging health problems in korea. Journal of Korean Medical Science, 29(5), 621. https://doi.org/10.3346/jkms.2014.29.5.621

Food and Agriculture Organization of the United Nations (Ed.). (1997). Drylands development and combating desertification: Bibliographic study of experiences in China. Food and Agriculture Organization of the United Nations.

The Asian Yellow Dust – Part 1

The Asian Yellow Dust – Part 1

Comments 0 Comment
Fig 1: Donning a mask is a common sight in South Korea, who battles the Misemongi yearly (source: Joel’s Travel Tips)

 

Following the most recent COVID-19 pandemic, people out and about on the streets with a face mask on is no longer an unusual sight. However in East Asian countries, specifically China and Korea, masks has been a necessity way before the COVID times. The reason for this is because cities in both countries suffer from poor air quality with a surprisingly natural origin.

 

Origins of the dust

Fig 2: The pathway of the Yellow Dust, originating from the deserts in China and Mongolia (source: National Institute of Meteorological Research)

 

The Yellow Dust that blows over East Asia originates from the arid and semi-arid regions of China, where the Gobi Desert and the Loess Plateau are located (Kar & Takeuchi, 2004). The composition of the particles in the Yellow Dust are mainly sand and soil dust, eroded through aeolian processes (Chung, 1992). During the months of spring (March to May) is when the Yellow Dust occurs. This is because as the weather warms up in the Northern hemisphere, it triggers a change in atmospheric pressure and triggers strong gusty winds as well as extratropical cyclones. These strong weather systems then transports the fine dust particles from the Chinese deserts eastwards towards major Chinese cities as well as Korea and Japan (Chung, 1992).

 

Health implications

The most obvious implications of the Yellow Dust on humans will be the health implications. Similar to the haze we face here in Southeast Asia, the Yellow Dust has particulate of sizes ranging from PM10 to PM2.5, both classified as fine and ultra-fine. PM10 particles are small enough to enter the alveoli in the lungs, while PM2.5 can permeate into the blood and lymphatic system, potentially even reaching the brains and fetal organs (Kang & Kim, 2014). The particles are also irritants, and can worsen existing conditions such as asthma and eczema.

 

Economical impacts

As the dust chokes up the city, it brings about economic downfalls as well, affecting an array of services. Firstly, as the dust is opaque and causes a decrease in visibility. Through a detailed economic analysis by Kang et al. (2004), it was estimated that South Korea’s aviation industry suffered half a million dollars lost in year 2002 from flight cancellations alone. As the dust causes health implications, it can affect productivity of the workforce, and discourage people from going outdoors, affecting various retail industries. the total cost of the Yellow Dust on South Korea in 2002 is estimated to be USD 5,600 million, or USD 117 per South Korean citizen (Jeong, 2008)

 

Any Solutions?

As the origins and causes of the Yellow Dust is inherently natural, it is difficult for governments to mitigate the onslaught of this particular type of air pollution in the city. As such, cities can only adapt through means like implementing cohesive guidelines for the public and monitoring the meteorological events closely to provide quicker alerts to its citizens.

 

References

Chung, Y.-S. (1992). On the observations of yellow sand (Dust storms) in Korea. Atmospheric Environment. Part A. General Topics, 26(15), 2743–2749. https://doi.org/10.1016/0960-1686(92)90010-I

Jeong, D.-Y. (2008). Socio-economic costs from yellow dust damages in south korea. Korean Social Science Journal, 35(2), 1–29. http://journal.kci.go.kr/kssj/archive/articleView?artiId=ART001293655

Kang, D., & Kim, J.-E. (2014). Fine, ultrafine, and yellow dust: Emerging health problems in korea. Journal of Korean Medical Science, 29(5), 621. https://doi.org/10.3346/jkms.2014.29.5.621

Kang, G. G., Chu, J. M., Jeong, H. S. Han, H. J., and Yoo, N. M.(2004). An Analysis of the Damage From YYellow Dust in Northeastern Asia and Regional Cooperation Strategy for Reducing Damage. Seoul: Korea Environment Institute.

Kar, A., & Takeuchi, K. (2004). Yellow dust: An overview of research and felt needs. Journal of Arid Environments, 59(1), 167–187. https://doi.org/10.1016/j.jaridenv.2004.01.010

Are we slowly poisoning ourselves by staying indoors too often?

Are we slowly poisoning ourselves by staying indoors too often?

Comments 0 Comment

People spend majority of their lives indoors today, be it at home resting, in an office at work, or when we go to malls for leisure during break-time. Hence, it is not surprising that there is an increased focus on the quality of air indoors, particularly in its Volatile organic compound (VOC) concentration. VOCs are compounds that evaporate easily. They are found in almost every household item. Some examples of VOCs include acetone (commonly found in nail polish removers), benzene (found in glue or carpeting) and terpenes (used in scented products such as soap or fabric softener). VOCs are seemingly unavoidable in everyday life and VOC levels are often disregarded and forgotten because of the lack of interest and knowledge about it. However, this should not be the case, as the impacts of exposure to VOCs are truly insidious.

 

Fig 1: Infographic on types and sources of indoor air pollutants (source: Andatech)

 

Death attributed to VOC exposure has accounted for an estimated 4.3 million deaths annually (WHO, 2014), and majority originates from less-developed nations where houses lack proper ventilation, and where citizens still rely heavily on gas stoves or wood-fired heating. Several kinds of VOCs such as benzenes are even discovered to be carcinogenic. Common acute symptoms for exposure to high levels of VOCs are eye, nose and throat irritation, as well as headaches and nausea. Breathing in VOCs also exacerbate asthmatic conditions, affecting children and elderly more so than adults.

 

Now, you might wonder then, if VOCs have many known side effects, why have we as a society, not done anything to mitigate this source of indoor pollution? Agencies have attempted to establish regulations, such as the Clean Air Act enacted by the US congress, which promises high standards in the nation’s air quality (UL, 2018). However, most regulations imposed on VOC emissions focus more on outdoor emissions rather than indoor emissions. Even if regulations are present, they are often filled with loopholes. For instance, the Japanese Government established a guideline for Indoor Air Quality (IAQ) which sets a standard for maximum indoor VOC levels in public buildings such as offices. However, such regulations cannot be fully implemented in households because government interventions within homes are considered a violation of personal freedom (Azuma, Uchiyama and Ikeda, 2008).

 

To help out the situation at home, regulations will have to be placed on the source of the pollution and not the homeowners. This means holding household product companies accountable for the chemicals they use. The US Environmental Protection Agency (EPA) website assures that there are national and international organisations that check and classify household products according to impact levels of indoor air quality on health such as irritation or chronic toxicity. However, this labelling and certification process is neither compulsory nor standardised, hence consumers might still run the risk of overexposure to harmful VOCs.

Through this post, I hoped I managed to raise awareness of the harms of VOCs, and encouraged consumers to be mindful of the products we use at home so as to protect ourselves from any onslaught of health implications.

 

References

World Health Organisations (2014) “Household (Indoor) Air Pollution.” 2014, November. Retrieved from http://www.who.int/indoorair/en/

UL PSi. (2018, April 20). Volatile organic compounds (VOCs): A brief regulatory overview. Retrieved from https://msc.ul.com/en/resources/article/volatile-organic-compounds-vocs-a-brief-regulatory-overview/

Kenichi Azuma, Iwao Uchiyama & Koichi Ikeda (2008, May) The regulations for indoor air pollution in Japan: a public health perspective, Journal of Risk Research, 11:3, 301-314, DOI: 10.1080/13669870801967119

Effects of light pollution on Urban Black Swans

Effects of light pollution on Urban Black Swans

Comments 0 Comment

As a continuation from the previous introductory post on light pollution, we look deeper into the impacts it has on bio-diversity, specifically wildlife that shares the urban space with us. As aforementioned, exposure to artificial lighting, specifically blue light, at night-time prevents the body from producing the sleep hormone melatonin. This is why it is worth once in a while to listen to mom and put your phone away before sleeping. Other lightings such as LED streetlights are also sources of blue light pollution.

Blue light pollution is known to cause sleeplessness in humans, but what about the urban wildlife? It was predicted that warmer, amber lightings with less short, blue wavelength helps in mitigating biodiversity impacts of light pollution, and cities have transitioned into adopting them. To test the validity of this prediction, animal behaviour researchers from Australia tested whether unfiltered white light (blue-rich) and filtered amber (blue-reduced) light from LED streetlights had any implications on the rest and melatonin production in black swans.

Fig 1: The cygnus astratus, or black swan, native to Australia (photo credit: google photos)

 

The swans are ideal test subjects as they are large and can be re-captured with ease. They are also diurnal, with relatively flexible sleep patterns. This meant that the black swans are relatively resilient to sleep disruption, hence the researchers predicted that if the swans are affected by the lights, then other more sensitive urban wildlife will have a greater impact. Quality of sleep of the swans were quantified using electroencephalogram (EEG) measurements and melatonin in blood levels. It is also good to note that the swans are exposed to urban lighting in a naturalistic manner, meaning the test site was constructed to be like a typical pond in the park.

The results of the study were unexpected; where the colour of the streetlights had no differing effect on the quality of sleep of the swans. The study also confirmed that the swans rested less under white night controls over dark controls, as seen from shorter rest durations (~30 mins less) and shorter REM sleep.

Fig 2: Results of light treatment affecting the sleep cycle of the swans (photo credit: Alusebrook et al. (2020))

 

There is much to take away from this. Several interesting explanations for these results were given. Firstly, it was suggested that perhaps the swans were more disrupted by amber lighting at night was the fact that unlike humans, the swans have greater visual sensitivity for light from the red and yellow spectrum, hence amber lighting for these diurnal animals might have further stimulated them at night. Melatonin levels in the swans were also non-conclusive due to the low levels detected overall, hence the study was unable to develop a conclusion linking melatonin production to colour of lighting for the swans.

Nonetheless, the results hinted that current mitigative measures of altering the colours of streetlights is not as effective as it was once predicted to be. It is therefore more advisable to turn off streetlights entirely, especially in parks, reserves, or where plenty of urban wildlife reside, to keep disruption from artificial light pollution to bio-diversity down to a minimal.

 

References

Aulsebrook, A. E., Lesku, J. A., Mulder, R. A., Goymann, W., Vyssotski, A. L., & Jones, T. M. (2020). Streetlights Disrupt Night-Time Sleep in Urban Black Swans. Frontiers in Ecology and Evolution, 8, 131. https://doi.org/10.3389/fevo.2020.00131

Skip to toolbar