Air pollution is dangerous to our lungs – and our eyes. Now that we’re leaving our houses masked up, we might not be recognising the familiar acrid odours attributed to ad-hoc bouts of haze, nor do we notice particles from Singapore’s ever-growing road traffic (electric vehicles are, after all, quite away from being a thing). The dangers of air pollution to our lungs and our lives have long been established. But did you know that there’s evidence to suggest that air pollution may also negatively impact our eye health?
According to a study published in the British Journal of Ophthalmology that examined some 116,000 residents in the United Kingdom, people who stayed in the most polluted areas were 8 per cent more likely to report having suffered from age-related macular degeneration, a chronic irreversible eye disease that causes loss of vision in the centre of the visual field (or the macula) because of damage to the retina.
Said lead author Professor Paul Foster of the University College of London, Institute of Ophthalmology: “Here we have identified yet another health risk posed by air pollution, strengthening the evidence that improving the air we breathe should be a key public health priority. Our findings suggest that living in an area with polluted air, particularly fine particulate matter or combustion-related particles that come from road traffic, could contribute to eye disease.”
To be specific, the pollutants in the air that these areas were facing include fine ambient particulate matter with a diameter of less than 2.5 micrometres – in other words, PM2.5 particles. These particles are microscopic and essentially invisible to the naked eye. They’re also potentially the most harmful particles in the air and is the main pollutant during haze. And as we’ve just read, they do more than just irritate the eyes.
While Singapore’s National Environment Agency (NEA) constantly monitors the country’s pollution levels, including PM2.5 particle concentration, it’s clear that air pollution cannot be totally attributed to periodic haze. Pollution, and PM2.5 particles, in particular, are caused by burning fuel and chemical reactions that take place in the atmosphere. Forest fires in dry seasons are other factors that contribute to this air pollution.
As such, we’re not saying it’s time to get overly anxious, nor are we suggesting that donning a pair of goggles along with your mask is in order. First off, note that the cross-sectional study is observational, not experimental – that is, despite the correlation that findings suggest, causality cannot be established just yet.
Furthermore, scientists are working to understand how PM2.5 and other pollutants may lead to age-related macular degeneration – preliminary suggestions include oxidative stress or inflammation. Pollutants in general were also associated with changes in the eye’s retinal structure.
Age-related macular degeneration is one of the leading causes of irreversible blindness among those over 50 years old in high-income countries. The eye disease is projected to affect almost 300 million by 2040, and known risk factors include smoking and genetic factors.
Another eye disease found to be associated with air pollution is glaucoma, a disease in which the optic nerve at the back of the eye gradually dies, causing blindness. A recent study conducted in the United Kingdom in 2019 found that participants who lived in areas with higher PM2.5 concentrations were 6% more likely to report a diagnosis of glaucoma.
Research has shown us that there seems to be some association between serious eye diseases and air pollution – and we can’t exactly stop pollution worldwide. For now, what’s certain is that air pollution, like all the other potential fallouts from ecological disasters, can be averted with decisive action – which begins with actions as simple as consuming greener products and recycling more.
Apart from that, we can’t treat haze as an annoyance to be ignored. You can make it a habit to check NEA’s website before heading outdoors and close all windows and use an air purifier if there’s one available.