Find out why your eyes tear, your throat hurts and your skin itches whenever the PSI soars.

Portrait of Tammy Strobel

Find out why your eyes tear, your throat hurts and your skin itches whenever the PSI soars.


You may sniff or tear more than usual whenever it’s grey and hazy outside. And on bad days, the choking air can cause you to start coughing, and develop a sore throat and skin rashes. What gives? Experts shed light on the different ways the haze can affect you.

Why do I get a sore, scratchy throat?
Haze contains irritants and particulate matter that can traumatise the lining of our air passages and throat, leading to inflammation, says Dr Valerie Tay, medical director and consultant ear, nose and throat specialist at Singapore Medical Group (SMG) ENT Centre. “This usually causes your throat to feel sore. The irritation can also lead to frequent coughing, which can further aggravate the inflammation of your voice box, which gives rise to pain and a hoarse voice,” she says.

Do my lungs get affected too?
“The PSI (Pollutant Standards Index) measures the concentration of particulate matter (PM) less than 10 microns in size, and PM 2.5 measures particles smaller than 2.5 microns in size. In general, the smaller the particulate matter, the easier it can penetrate your lungs,” says Dr Tay. She adds that PM 2.5 is more dangerous as it can enter deep into the small sacs of your lungs and may even be able to cross into your bloodstream. It is also thought that PM 2.5 can trigger inflammation and oxidative damage, hence increasing the risk of plaque formation in the blood vessels.

Is haze similar to secondhand smoke?
They may smell the same, but they’re different. “Haze is an accumulation of dust, smoke, exhaust and other particulate matter in the atmosphere. While it’s also made up of fine particulate matter and harmful toxic chemicals, its components are not the same as that of second-hand smoke from cigarettes,” explains Dr Tay.

Why do my eyes sting and tear?
“The tiny particulate matter, together with the polluting gases like sulphur dioxide and carbon monoxide in the atmosphere, come into contact with and irritate the outer layers of the eyes, which are called the conjunctiva,” says Dr Daphne Han, medical director and consultant ophthalmologist at SMG Vision Centre, Gleneagles Hospital. This causes an allergic reaction that gives rise to dilated conjunctiva blood vessels and makes eyes look pink. Eyes may also become drier, and you may experience a sandy or gritty feeling in your peepers from both the dryness and the physical contact with the particulate matter and gases, she adds. If you also experience tearing or become extremely sensitive to light, it may point to a more serious condition like dry eyes or allergies.

Will there be any permanent damage to my eyes?
Symptoms of eye irritation from long-term exposure to pollutants are generally temporary, says Dr Han. “The irritations stop once the haze goes.” Only in some rare cases, eyes may suffer from scarring if there’s been an exceptionally severe allergic reaction. Why does the haze irritate my skin? “Dust particles can be extremely drying to the skin, and may also clog your pores,” says Dr Gavin Ong, medical director and consultant dermatologist at The Skin Specialist. He adds that the accompanying chemicals in the air can also trigger skin irritations. “Furthermore, hazy skies give the impression that the amount of sunlight shining through is less than usual, when, in fact, the ambient ultraviolet (UV) light is still high. The damaging combination of UV rays and haze can accelerate skin ageing,” he adds.

Do I need to change my skincare regime when the air is polluted?
Those with sensitive skin may require more frequent washing to remove the build-up of dust particles and chemicals on their skin. Dr Ong suggests choosing a non-drying cleanser to prevent your skin from getting stripped of moisture, then using a rich moisturiser to enhance its repair and renewal. Topical antioxidants are also very helpful in reducing damage from all the free radicals generated by the haze and the environment.

Can long-term exposure to the haze cause further health complications?
Studies have shown that long-term exposure can cause both lung and heart disease. However, Dr Tay points out that short-term exposure is likelier to affect your upper respiratory tract, giving rise to a cough, runny nose and throat irritation.