The biggest hazard of the haze that we see year after year here in Singapore is the fine particulate matter (PM) suspended in the air. Particulate matter, especially those referred to as PM2.5 can easily be inhaled into our lungs and can go deep into the respiratory system.
This refers to particles that are smaller than 2.5 micrometres in size. Inhaling them can cause acute symptoms such as cough, wheezing, shortness of breath and a feeling of tiredness and weakness.
Read more about How PM2.5 affects your health
Something you also need to know is that exercising outdoors during the haze period is more likely to be harmful to your health. When the haze level is in the unhealthy range (high PSI or high concentration of PM2.5), it is prudent for everyone to avoid outdoor activities.
Short-term effects of the haze on health
Short-term exposure of healthy individuals (i.e. continuous exposure to unhealthy daily average PSI levels over a period of a few days) to high levels of haze particles may cause irritation of the eyes, nose, and throat. The irritation resolves on its own in most cases.
Note, however, that the particles can affect the heart and lungs, and they are especially risky for people who already have heart or lung disease. It can take up to 3 days after the exposure to manifest any health symptoms.
Learn more about the PSI- Pollutant Standard Index in Singapore
Long-term effects of the haze
In the case of Singapore, there is no robust data on the longer-term effects of exposure to haze. This is due to the seasonal occurrence that we experience here and the exposure may vary from year to year, while international studies are based on long term continuous exposure to air pollution.
However, studies conducted in other regions have shown that people with continuous exposure over several years to high pollution from fine particles may have a higher risk of cardiovascular effects such as heart attacks, reduced lung development, as well as the development of chronic respiratory diseases, such as asthma, in children.
Usually, the harmful effects of a few minutes of haze exposure are temporary and do not lead to long-term health issues.
Nonetheless, studies performed in the US and Europe, have found a relationship between air pollution and cardiovascular and lung cancer death. It showed a 36% increase in lung cancer rate for every increase of 10 micrograms of PM2.5 per cubic metre.
Which are groups of people more sensitive to haze?
Children, elderly, and people with chronic heart or lung disease are more vulnerable to the health effects of haze. You should consult your doctor if you develop any breathing difficulties. Also, pregnant women should reduce exposure to haze for the health of their baby.
People at highest risk of being affected by the haze should remain indoors. Particularly, children and the elderly who have smaller lung reserves should avoid prolonged exposure to the haze.
After seeing all of that, it is clearly better to stay indoors during hazy situations when the PSI and PM2.5 are at unhealthy levels. Just keep in mind that those particles from outside also can get easily into your house, so even by staying indoors, you can’t guarantee that you are not getting exposure.
If you want to ensure that you are breathing clean air indoors, the best solution is to get an air purifying system. Make sure you buy an air purifier with HEPA filter because it can ensure the maximum rate of pollutant removal.
Learn more about Indoor Air Quality
Where can I get more information on haze?
Please refer to the following official websites: