LETTER | Our memories are shortlived, so there may be a need for a reminder on this as we struggle to deal with the current extremely poor air quality; a problem that has plagued us for two decades. 

The announcement that our National Disaster Management Agency (Nadma) has sent 500,000 face masks to Sarawak to support the worsening trans-boundary smog from Indonesia is not reassuring. 

From all available information, the masks sent are three-ply surgical masks and of little value. 

It is important that misinformation and misleading actions not be created by government sources as it may confuse the average person on the street.

I will discuss, in FAQ style, the key issues regarding the value of face masks in the face of this recurrent crisis.

Are normal surgical masks useful? How long do they last?

It is important to recognise that most of the harmful substances in the smoke/smog coming our way consist of toxic gases and very small particles, most under 2.5 microns in size. 

Analysis of the air coming from the Indonesian haze suggests that the chemicals we are inhaling include ozone, carbon monoxide, cyanide, ammonia, formaldehyde, acrolein and benzene; some with long-term carcinogenic effects. 

In addition, the ultrafine particulate matter (PM 2.5 microns or less) often lodge deep in the lungs and have short and long-term effects on cardiovascular and pulmonary diseases. 

The single-ply surgical masks (usually white) are ineffective. The usual three-ply surgical masks (usually green or blue and thicker) also cannot filter toxic gases and fine particles.

It may offer some protection against larger particles that irritate, hence may be useful for some exposure outdoors, on a bike, etc. 

Even the Health Ministry advisory on the usage of personal protection during the haze says: “Airborne particles causing haze may be as small as 2.5 microns. The use of the surgical mask will not prevent one from inhaling the small airborne particles.”

Once these surgical masks are damp (wet) or you cough or sneeze in them, they are ineffective. They last at best 30 to 60 minutes; so they need to be changed very often.

You may argue that sending 500,000 three-ply surgical masks to Sarawak is 'at least doing something and is better than doing nothing'. 

But if they last one hour and are largely ineffective, who are we fooling? Why waste this expense, which could be put to better use to fight the real problem and, more importantly, not mislead the public.

What about homemade or purchased cloth masks?

Many have resorted to the use of cloth masks as they are cheaper and can be washed and reused. A number of studies have shown that they are largely ineffective for PM 2.5 microns (and below), as well as for the toxic elements in smoke. 

They also retain moisture easily and increase your risk of getting an infection. Wearing a face mask may give you a false sense of security; you think you are protected when in fact you are not.

Do N95 masks protect against the haze?

N95 masks are named as such because they filter at least 95 percent of airborne particles. They are more effective, but only if worn correctly with a good fit to the face of the wearer. 

They work only if air comes in via the filter. Leaving gaps means the mask fails to offer protection. 

N95 masks are not easy to wear for long, they increase the effort of breathing, reduce the volume of air and can cause discomfort. 

Care is required in their use in the elderly, children or those with cardiac or lung conditions. 

There was a recent suggestion to keep a ‘small window’ in the mask to help children breathe easier, but this defeats the mask’s function. 

N95 masks are not that cheap and do have to be changed periodically.

Is staying indoors useful? Will closing all our windows/doors and using air conditioners and air purifiers work?

The general opinion is divided on this. Generally the air we are breathing outside and inside the house is the same. 

The reason to stay indoors is to decrease outdoor activities and decrease our exertion. Exerting ourselves means breathing in more of the toxins faster and increasing tissue damage. 

If we close all entry points, some studies have shown the build-up of harmful toxins indoors. 

Air conditioners cannot filter out fine particles and gases and also damage the environment further (2°C rise in city temperatures with rampant air conditioner use). 

Those selling ‘air purifiers’ make lots of claims that still require detailed studies on their efficacy and may not be effective.

Will our long-term health be affected by the smog? How about our own ambient pollution levels?

Authorities want to reassure us that breathing in smog for a few months every year for decades is harmless. No one believes this. 

There is some immediate effect in terms of respiratory irritation, but breathing in the chemicals mentioned above will in the long term result in a significant impact on lung and heart health and cancer risks, with an increase in premature deaths.

We must see this seasonal haze problem in the context that more than 90 percent of our population is consistently exposed to PM 2.5 levels, which is above World Health Organization recommendations. 

So our daily background exposure are already exceeding safe standards and these yearly spikes for one to two months exacerbate our worsening air pollution and health.

We require honest, meaningful responses from our government and a decisive plan to end the current crisis and prevent the yearly occurrences. 

Already, we are paying the unrecognised price from two decades of seasonal pollution from our neighbour, with possibly thousands of people with shortened lifespans each year. 

We cannot continue with this in the face of our worsening local ambient air pollution.

DR AMAR-SINGH HSS is a senior consultant paediatrician.

The views expressed here are those of the author/contributor and do not necessarily represent the views of Malaysiakini.