In 2007, Saketaram Soussilane and his wife, Christelle, were working in finance in Paris but keen for a change of scenery. Hong Kong ticked all the right boxes: it was safe, multicultural and had nature trails close to the city so the couple could indulge in their love of hiking. Starting a family was also part of their Hong Kong plan, so when Kalyan was born in 2011, the couple were over the moon. But when he was about 18 months old, Kalyan developed respiratory problems, coughing at night and wheezing during the day. Feeling helpless, the couple visited doctors, who diagnosed their son as having chronic asthma and prescribed him antibiotics, inhalers and anti-allergy drugs. “All the doctors said ‘This is Hong Kong, there is pollution, so just take these drugs’,” says Soussilane, who was born in South America to Indian parents and raised in France. The symptoms disappeared but the problem was still there. “The doctors only cured the consequences, only masked the symptoms,” says Soussilane. This realisation triggered what would become an obsession with air quality and ultimately a career change. He eventually left his job in finance to set up Meo, a company that helps building owners turn properties green by improving their indoor air quality and reducing energy wastage. “We didn’t want to leave Hong Kong, so I was determined to find the origin of my son’s problem,” says Soussilane. When he read the results of a study that found breathing air in polluted cities such as Hong Kong is like smoking two packs of cigarettes a month, it increased his drive. The lungs: how they work, what the coronavirus does to them Addressing air pollution is complicated, as the biggest pollution sources are processes that people rely on daily, such as fuel combustion in vehicles, industrial facilities and power generation. United efforts by governments, both locally and globally, are needed to find solutions. But there is a growing movement of people at the grass-roots level who are doing their bit. Soussilane is now one of them. An electrical engineer specialising in robotics and signal processing, Soussilane started collating data relating to the levels of fine particulate matter (PM2.5), the tiny and dangerous particles responsible for hazy air pollution, in his Central neighbourhood and other parts of Hong Kong, creating an air-quality monitoring system that measures dust and toxic gases. Soussilane found that pollutant levels fluctuated wildly – not just daily, but hourly. To discern patterns, it was vital to measure levels continuously, focusing on indoor air quality “because we spend 80 per cent of our time indoors, in offices, schools and the home”. Shopping malls in Hong Kong had clean air, he discovered, but it came at a high cost, both financially and environmentally, as the energy they used was mostly produced by burning coal. “Air conditioning accounts for 10 per cent of worldwide electricity consumption. I call it the clean air paradox – cleaning inside air while polluting outside air.” The home, he says, contains a “cocktail of pollutants” as a result of poor ventilation and poorly maintained air conditioners, chemicals from cleaning products, and toxins contained in new furnishings. “Properly ventilating your home is an easy way to improve air quality. Open your windows and let the fresh air flow,” he suggests, adding this is even more vital now during the coronavirus pandemic . Applying air filters to air conditioners also helps, and the filtering materials are readily available in Hong Kong. In July, a study by the University of Hong Kong and China’s Sun Yat-sen University and Southeast University found Covid-19 risk was linked to poor ventilation. Researchers found that virus particles could infect people several metres away in rooms with poor air circulation. Last week in Australia, investigators at hospitals in the southern city of Melbourne also linked poor ventilation and air flow with the spread of the coronavirus. We must put pressure on those who manage school, office and residential buildings to make sure they are doing their best to improve the quality of the air we breathe Sakethram Soussilane Chan Wing-kai of the Hong Kong Asthma Society says air conditioners should be regularly maintained, as they harbour dust and allergens that can aggravate respiratory conditions and allergies . “It’s important to keep air conditioners clean, as they can harbour dust and allergens that are deposited in the unit’s dust filter, and those allergens can potentially trigger asthma and allergy symptoms,” says Chan. The Hong Kong Consumer Council recommends cleaning dust filters once or twice a month. The effect of poor air quality on health and well-being is well documented. The World Health Organization (WHO) estimates air pollution kills seven million people worldwide every year. The global Institute for Health Metrics and Evaluation (IHME) based in the US state of Washington estimates that in 2017, 1.6 million people died prematurely as a result of indoor air pollution – three per cent of global deaths. In low-income countries, it accounts for six per cent of deaths. Earlier this month, air pollution was found to be a significant factor in the death of a nine-year-old girl in London, the first time a British coroner has cited poor air quality as a cause of death. “If you read WHO reports, it says that 91 per cent of the world’s population live in areas that exceed the health body’s air safety regulations,” says Soussilane. Studies have shown that poor air quality also impairs learning. Research published this month on Science Daily by the University of Utah in the United States found that more frequent exposure to peak air pollution levels was associated with reduced test scores for third graders. Soussilane says making small changes in the home, such as adding filters to air conditioners and creating air flow, significantly reduced his son’s asthma. Kalyan is now nine and his other child Narayan, aged six, has no respiratory issues. Beat bad air quality: three ways to cope with air pollution “We must put pressure on those who manage school, office and residential buildings to make sure they are doing their best to improve the quality of the air we breathe,” Soussilane says.