|1||Phra Samut Chedi, Samut Prakan|
|3||Bang Lamung, Chon Buri|
|4||Samut Prakan, Samut Prakan|
|6||Samut Sakhon, Samut Sakhon|
|7||Si Chiang Mai, Nong Khai|
|8||Bang Khun Thian, 曼谷|
|10||Pathum Wan, 曼谷|
|1||Nai Mueang, Mueang|
|2||Jiraruj Pediatric Clinic|
|3||Maharat Nakhon Ratchasima Hospital - Pediatric Building|
|星期二, 1月 19|
对敏感人群不健康 136 美国 AQI
|星期三, 1月 20|
不健康 156 美国 AQI
|星期四, 1月 21|
不健康 152 美国 AQI
不健康 153 美国 AQI
|星期六, 1月 23|
对敏感人群不健康 102 美国 AQI
|星期日, 1月 24|
对敏感人群不健康 104 美国 AQI
|星期一, 1月 25|
对敏感人群不健康 106 美国 AQI
|星期二, 1月 26|
中等 84 美国 AQI
|星期三, 1月 27|
中等 66 美国 AQI
|星期四, 1月 28|
中等 66 美国 AQI
Nakhon Ratchasima, otherwise more commonly known as Korat, is a city located just north east of Bangkok. As with any city located near to the country’s capital, there are bound to be problems related to the close proximity and subsequent decline in air pollution, which can be examined in depth. In the year of 2019, Korat came in as the number one most polluted city in the whole of Thailand. This is quite an achievement due to the high number of polluted cities that inhabit the country, with even the capital being famous for its huge clouds of smoke and haze lingering in the atmosphere, with spells so prominent before that there have been incidences of schools having been closed, and transport and travel disrupted due to the haze spells that appear and refuse to dissipate even after several weeks.
The PM2.5 reading that earnt it this number one spot during 2019 was 42.2 µg/m³, putting it into the ‘unhealthy for sensitive groups’ bracket. In order to get a rating such as this, the PM2.5 levels need to be between 35.5 and 55.4 µg/m³. These numbers would indicate that the pollution levels in Korat would be of concern for a large amount of people to breathe every day, with demographics such as young children, the elderly and immunocompromised being at higher risk, hence the title of unhealthy for sensitive groups.
Among other months of the year, two came in at a higher reading in the next bracket up, the ‘unhealthy’ grouping which means that the air would have detrimental effects on anyone who is breathing it, and not just the sensitive section of the population. These months were February and March, which came in with readings of 67.9 and 68 µg/m³ respectively. An unhealthy rating requires a reading of anywhere between 55.5 to 150.4 µg/m³, a fairly high number of PM2.5 even in the lower end of the bracket. Although there is some data missing during the latter part of the year, the overall numbers recorded and averaged out shows that Korat, or Nakhon Ratchasima, is indeed a very polluted city, subject to large spikes in PM10 and PM2.5 that can be dangerous for its inhabitants, with preventative measures and staying up to date on the pollution levels being of increasing importance for those that want to protect themselves from the host of side effects that can arise from breathing such polluted air.
There are a multitude of reasons that contribute to the high levels of air pollution seen in the city, with some being more recent and others going back many years further. Traditionally, the economy of Korat was heavily driven by agriculture, and this continues on until today in modern times, with a large amount of demand for the cities sugar, rice, sugarcane plants and tapioca. As a result of this and due to large scale globalization of such industries, they see considerable growth and as such more factories, farms and means of production are needed to support their ever-growing output.
Oftentimes in areas that see large scale production of organic products, there will be pollution coming from the burning of said organic material. This has a whole host of problems, as the burning of these organic wastes and refuse on a large scale can release a multitude of chemical compounds and pollutants into the air. Rice as well as sugarcane farms often see burning occurring, despite this being a somewhat illegal practice. However, this though it continues to occur, lacking the proper enforcement as well as the difficulty of stopping it from occurring, due to the large amounts of farms that find themselves on the city limits and indeed across many rural areas, not only unique to Korat.
Burning the aforementioned materials can lead to the production of volatile organic compounds (VOC’s) as well as the production of black carbon. Both of these are produced from the incomplete or improper combustion of organic materials, as well as the combustion of fossil fuels. Black carbon, which is the primary component of soot, has a whole host of issues both to health as well as the environment, being a chief contributor to climate related issues and global warming.
Volatile organic compounds, known as ‘primary pollutants’, can combine with other chemicals in the air to form more dangerous particles and forms of pollution, that often see themselves gathering in the thick clouds of smog and haze that permeate the air during the countries worse months. They are known as primary pollutants because they are emitted directly from an offending source, such as a fire or other combustion methods. Secondary pollutants are ones that are formed when primary ones undergo chemical reactions in the atmosphere to form noxious compounds, such as sulfur dioxide (SO2) and nitrogen dioxide (NO2). Of note is that nitrogen dioxide can be simultaneously a primary and secondary pollutant, due to its ability to be formed directly from vehicular emissions, as well as forming later on in the air as a secondary pollutant.
Whilst the issue of pollution and smoke coming from farms has been discussed, there are many other sources that play large roles in reducing Korats air quality and giving it its number one ranking out of all of Thailand’s cities.Another would be a source that plagues many cities in Thailand and indeed the rest of the world, that of vehicular emissions. There are nearly 10 million registered vehicles in Bangkok alone, and as such many nearby cities would also have a high concentration of vehicles, with cars, motorbikes and both trucks and buses filling the roads and air with high volumes of exhaust fumes and smoke.
Vehicles that run on diesel fuels can have a greater contribution to rising PM2.5 levels due to the chemical composition of diesel fuel and what it releases upon combustion. Since diesel is a fossil fuel, it also releases the previously mentioned black carbon particles as well as volatile organic compounds, causing a greater percentage of these materials to be released into the atmosphere when figured in with crop and organic matter burning. Cleaner fuel sources are becoming increasingly more sought after for cities across the globe, and a reduction in the use of diesel fuels would go a long way in terms of eradicating rising pollution levels.
Besides pollution arising from vehicles and the agricultural sector, dust and fine particulate matter can gather on the roads from multiple sources, including improperly maintained construction sites as well as factories. There are a number of garment and textile factories located in Korat, often relying on the burning of coal for their energy. This in turn produces more soot which can flood nearby areas and accumulate, with other materials present as a byproduct from big industries, such as mercury, lead, microplastics and a variety of other toxic materials all making their way into the air in the form of PM10 or PM2.5.
The previously mentioned poorly maintained construction sites are responsible for giving off a lot of finely ground dust that contains many of the aforementioned metals and micromaterials. When combined with factory soot and vehicular emissions, these finely ground particles can all combine to cause a phenomena known as road dust, whereby thick accumulations of soot and other fine particles find themselves gathering in large amounts over motorways and roads, and with a high volume of cars and trucks travelling over them, can send the fine material billowing up into the atmosphere, where it can cause PM2.5 levels to rise to dangerous numbers, as well as combining to form further toxic compounds. These are the other sources and forms of pollution that are present in Nakhon Ratchasima.
With a city that regularly sees pollution readings of moderate, all the way up to unhealthy (in terms of levels of PM2.5 recorded in the air), naturally there would be an increased instance of having health problems amongst its population. Elevated levels of PM10 in the air can enter into a person’s airways and cause symptoms such as aggravated asthma attacks, irritation to the throat, nose and eyes, as well as an increased risk of chest infections. Inhalation of the much smaller PM2.5 particles can cause significantly more damage to health, due to its ability to penetrate deep into the body’s tissues. It can enter via the lungs and find its way deep into the respiratory system, where it can accumulate and cause a whole host of pulmonary disorders, or find its way into the bloodstream where it can spread to many different areas of the body.
In terms of lung damage, PM2.5 can cause issues such as chronic obstructive pulmonary disease (COPD) which includes within the term a host of ailments such as bronchitis, emphysema, reduced lung function and chronic coughing. Particle matter such as black carbon, also due to its small size, can cause damage to the heart, lungs, blood vessels and even bring about birth defects in children who are exposed In Utero via the mother breathing the polluted air.
The previously mentioned metals such as lead and mercury can also cause stunted growth and developmental issues amongst children, due to their capacity to build up within the body and damage the nervous system and other bodily functions. In regards to the factories, or indeed in the rarer but not unheard-of cases of refuse burning (which can contain plastics and other dangerous to burn materials) can release plastic fumes which when inhaled can cause dizziness, headaches, skin irritation as well as damage to the renal and hepatic systems (kidneys and liver). Being aware of the whole host of issues that breathing such polluted air can bring, it could be in many people’s interest to take preventative measures when pollution levels are elevated, such as the wearing of particle filtering masks or avoiding outdoor activities. Of note is that these risks are not as significant for months that come in with moderate ratings, but the risks rapidly grow in correlation with the level of PM2.5 in the air and its associated rating.
In order for such a highly polluted city to have results in reducing its air pollution, certain initiatives are being taken that are more likely to have lasting, or at least temporary effects in the reduction of air pollution. But as with all environmental efforts, particularly in countries that are still undergoing heavy development, they can be hard to maintain, as over time day to day life continues to go on for its citizens.
However, stricter enforcement against black smoke emitting (diesel fuel based) vehicles have been imposed, getting more and more stringent with each passing year. And although they continue to find their place on the roads and highways across Nakhon Ratchasima and indeed many other cities across Thailand and the rest of south east Asia, a reduction in their number will have a direct reduction on the bad air quality.
Air quality monitors have been installed in several areas to monitor PM2.5 readings across the roads, and with the readings now more readily available, comes a more concentrated effort to reduce road traffic, particularly in sensitives areas such as near schools.
Other attempts are made such as saturating the air with water to wash out the excess dust particles, or in a more extreme version of this practice, seeding the air, which essentially means creating artificial ran clouds that can clean the air and roads of dust buildup. However, it has been noted that efforts such as rain seeding are temporary in nature and fail to address the root cause of air pollution buildup. Lastly more concentrated efforts are being implemented to stop the burning of crops and plantations, with sugarcane and rice ones being the most subject to this practice. A cessation of crop burning is also another step in the right direction to reducing levels of air pollution permanently.