Fight the PM2.5 war for clean air now

Promphat Bhumiwat
Dr. Kannika Thampanishvong

The annual toxic haze season in over, and now that the public has into forgotten about it, there’s another health hazard – known as Covid-19 – to worry about.The pandemic is expected to begin petering out months (or at worst, a year) after the world reaches herd immunity. But PM2.5 pollution will keep returning, causing massive economic and health problems every year.

Without effective policies to curb the rise of PM2.5 pollutants, the health and environmental impacts will soon become too acute, causing unimaginable health costs and destroying the country’s economic standing in the competitive global arena. As such, Thailand needs to solve the toxic PM2.5 haze at its root causes and quickly.

Sources of PM2.5 differ depending on geographical location. In rural areas, a major source of the pollutant is the open burning of agricultural waste. In big cities, the most significant source of PM2.5 pollutants, which needs to be controlled, is exhaust fumes from motor vehicles. This problem is particularly grave in big cities such as Bangkok, which has a large number of cars that contribute to its global notoriety for traffic gridlock.

PM2.5 is found in the exhaust fumes of motor vehicles as a byproduct of inefficient combustion in engines. The concentration of PM2.5 in exhaust fumes depends on many factors, such as the engine, emission control technology, the type of fuel used, and the age of the vehicles.

To reduce PM2.5 emissions, Thailand has adopted European emission standards. Set up by the European Union, these standards are divided into two categories: exhaust emission standards and fuel standards. There are six levels of emission standards, from Euro 1 to Euro 6. The higher the level, the pollutant emitted is less toxic. Currently, Thailand is using Euro 4 as its emission and fuel standards for new cars. However, there are still a large number of old cars on the road with emission standards lower than Euro 4.

The Thailand Development Research Institute (TDRI) conducted a study on measures to control PM2.5 emissions from vehicles, which found that effective measures depend on close collaboration between the government and car manufacturers and behavioural changes among consumers. A balanced implementation between mandatory measures from the government and voluntary efforts from the drivers will contribute to an effective reduction of PM2.5 pollutants.

First, the government should raise the emission standards on both vehicles’ exhaust and automotive fuel, from Euro 4 to higher levels, which would further reduce the emission of PM2.5 and other toxic particles. However, without supplementary measures, raising the Euro emission standards alone won’t significantly reduce PM2.5 emissions.

Among them is managing the number of old cars which contribute to high levels of emissions. Examples of measures to control the number of old cars include setting a progressive rate for annual vehicle taxes and putting an age limit on vehicles. These measures have proven effective in many countries.

In Malta, for instance, the older the car, the higher the annual vehicle tax. As a result, vehicle owners are motivated not to keep their cars too long. Another effective measure is state promotion through various forms of subsidies on zeroemission electric vehicle purchases.

However, the government should carefully consider how these measures will affect various stakeholders, to ensure that they will improve air quality efficiently while still being cost-effective.

For example, the government should have a transitional period when raising the Euro emission standards, so manufacturers of cars, petrol and auto parts have sufficient time to adjust.

Also, the government should provide subsidies and/or other support for old car owners when introducing age limits on vehicles. There are many old car users in the country, many of whom are on low incomes and will certainly face financial hardship if forced to buy new cars.

In terms of behavioural changes on car users’ part, the government should promote and further develop the mass transport system in order to reduce reliance on private vehicles. For this to succeed, the government must make mass transit comfortable and convenient. An extensive network is crucial and fares must also be affordable.

To reach those goals, authorities should have a clear timeline by dividing them into three phases: short, medium and long term.

Short-term measures should include implementing strict vehicle inspections, particularly on older diesel-engined vehicles, developing a database for emissions as well as raising public awareness to foster understanding about the dangers of PM2.5 and how people can protect themselves.

In the medium term, the government should introduce higher Euro standards on emission and fuels, reform the annual vehicle tax structure and begin rolling out measures aimed at reducing the number of old cars in the system.

In the long term, the government should adopt a more comprehensive strategy to help the public switch to more environmentally friendly vehicles such as electric cars. In conjunction with that, the mass transport system must be expanded to serve passengers efficiently and comprehensively.

Along with these measures to reduce emissions from automobiles, there must be a simultaneous effort to tackle toxic pollutants from other sources, such as agricultural burning and heavy industries.

Through concerted efforts to reduce the emission of highly hazardous PM2.5 from all major sources, it is possible to bring clean air back into our lives once again.

Kannika Thampanishvong, PhD is a Senior Research Fellow and Promphat Bhumiwat is a researcher at the Thailand Development Research Institute (TDRI). Policy analyses from TDRI appear in the Bangkok Post on alternate Wednesdays.

First Published : Bangkok Post on Wednesday, May 12, 2021 

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