Manila的空气质量

What is the air quality index of Manilla?

Manila is the capital city of the Philippines and is located in the northern region of Luzon. The Philippines consists of over 7,500 separate islands but commonly thought of as being split into three groups; Luzon, Visayas and Mindanao (from north to south). A 2020 estimate puts the population of Manila at just over 109 million people.

In December 2020 the average air quality, according to statistics released by the IQAir.com website, was classed as “Good” according to recommendations made by the World Health Organisation (WHO). This figure was 25 US AQI with a PM2.5 concentration of 6.1 µg/m³. The 2019 average for Metro Manila was 18.2 US AQI which placed it as the 5^th most polluted city in all of the Philippines. This PM2.5 reading of 18.2 µg/m³ placed it in the “Moderate” category (12.1-35.4 µg/m³).

What are the main sources of air pollution in Manilla?

According to a report which was published in 2016, 80 per cent of Manila’s pollution comes from the traffic plying its roads on a daily basis. The remaining 20 per cent comes from stationary sources such as factories and open burning of fossil fuels.

Outdoor air pollution can be described as a mixture of chemicals that react with each other to form tiny hazardous particles. Particulate matter and biological matter also combine with these elements.

Jeepneys are buses and the most popular means of public transportation ubiquitous in the Philippines. They are usually front-engine and rear-wheel drive, most often using diesel as its type of fuel. Many jeepneys are now very old vehicles and are often very unsafe and as such produce a lot of pollution.

Possibly because of the fact that the Philippines is spread over so many islands, it comes as no surprise to learn that they is no significant rail service which operates here. In 2019 there were just 79 kilometres of track. There are plans under consideration to extend the network by up to 244 kilometres to try and reduce other traffic on the roads.

Manila itself is served by 3 rapid transit lines which are all currently expanding their track lengths.

Is the air quality in Manilla getting better or worse?

At the start of a new year, the levels of air pollution skyrocket because of the use of fireworks as part of the celebrations. The monitoring station at the De La Salle University (DLSU) in Manila recorded a PM2.5 level of 448 µg/m³ (micrograms per cubic metre). At 2 a.m. on the same day, the air quality monitoring stations in Pasig City and the Ateneo de Manila University in Quezon City recorded PM2.5 levels of 397 and 369 µg/m³, respectively. With figures as high as these, the air pollution falls into the “Extremely dangerous” category where quality face masks are highly recommended for use outdoors. The advice is to stay indoors, if possible. At other times of the year, readings are more acceptable with DLSU recording levels at 7 to 182 µg/m³; Paranaque, 6 to 18 µg/m³; and Muntinlupa with levels between 8 and 42 µg/m³.

During the lockdown which was enforced as a way of trying to contain the spread of COVID 19, many vehicles stopped driving into the city as part of their commute. Within mere days, the air was seen to be clearer and residents were able to see the majestic mountain range of the Sierra Madre which is on the outskirts of the city but is rarely seen due to being obscured by the thick haze which normally hangs over Metro Manilla.

What are the health effects of Manilla’s polluted air?

Air pollution accounts for 1 in 8 deaths worldwide, which equates to approximately 7 million deaths in 2012, according to the latest data from the World Health Organisation (WHO). The findings doubled previous estimates from just four years ago in 2008. The World Health Organisation (WHO) now classifies air pollution as the world’s largest single environmental health risk.

The local authorities in Metro Manila operate and maintain 13 air quality control stations and more are planned to be introduced in order to get a more complete picture for the entire metropolis.

Nitrogen dioxide (NO₂) and PM2.5 are inextricably linked to severe cardiovascular and respiratory health illnesses. It has been medically proved that exposure to these pollutants adversely affects the body’s natural defence systems against viruses and COVID 19.

The concentration of PM2.5 Particulate matter is the key to identifying air quality. Particulate Matter comes mainly in two noticeable sizes, PM 2.5 and PM10. The number value indicates the diameter of the substance. PM2.5 are particularly hazardous because of their size. On that microscopic scale, they can easily bypass the body’s natural defence system and penetrate deep inside the lungs. Once in the lungs, they travel to the base of the bronchial tubes where they lodge in the alveoli. These are the millions of air sacs that a body has to exchange oxygen for carbon dioxide. From here, they can also enter the bloodstream.

What can be done to improve Manilla’s air quality?

Jeepneys and other Public Service Vehicles which are 15 years or older are being phased out gradually in favour of the more efficient and environmentally friendly Euro 4 compliant vehicles. E-Jeepneys are also to be sold alongside the gasoline engine ones.

After the return to normality after being in lockdown, several groups who had noticed the vast improvement in air quality called for the government to take action and put measures into place which would safeguard the air quality of the city. If the government is willing to take this opportunity and use the lessons learned due to the COVID 19 precautions, it could re-evaluate the infrastructure, encourage active mobility and micro-mobility and invest in efficient public transport systems capable of carrying the masses in a safe and environmentally friendly manner.

Unless measures such as these are implemented, then the air quality will once again deteriorate and Manilla will return to its old, dirty self.

The report studied levels of PM2.5 and nitrogen dioxide (NO₂) and noticed the dramatic drop in values once the lockdown took hold. The largest differences were noticed in the two main commercial centres; Manila and Quezon City.