SINGAPORE - Long-time smoker Loh Choo Kiat, 46, is well aware of the harm of second-hand smoke.
That is why he never smoked at home. Despite this, his daughter and son, who are aged eight and six, often suffered asthma attacks.
His son had serious attacks every three to four months. Sometimes, he had to be hospitalised.
Yet, Mr Loh was certain that the episodes were not linked to his habit. "I don't smoke in front of my family, so I thought it was fine," he said in Mandarin, adding that he would smoke either in the corridor outside his flat or go to the ground floor. His 43-year-old wife works in a construction firm.
Although his son's paediatrician had asked him to quit several times, the retail business owner, who smoked one pack of cigarettes daily, routinely ignored the advice.
It was a conversation with a health-care volunteer, who explained how smoking can leave toxic residue on nearby surfaces and even on his clothes, that changed his mind.
Indeed, toxins from cigarettes can remain long after second-hand smoke has dissipated from the air. This harmful residue that gets left behind is termed "third-hand smoke", a relatively new concept which was first coined in 2006.
Early research has found that third-hand smoke can cling to hair, skin, clothes, floors, walls, furniture, carpets and vehicles.
And it is not easy to get rid of, said Dr Teoh Oon Hoe, who heads the respiratory medicine service at the paediatrics department of KK Women's and Children's Hospital. "The residue cannot be eliminated by airing out rooms or by using fans and air-conditioners," he said.
"The best and only way is to create a smoke-free environment - at home, in the family vehicles and in public places."
When Mr Loh decided to take this step, he was aided by I Quit, a national anti-smoking campaign run by the Health Promotion Board, whose staff made regular phone calls to check on his progress and offer tips.
For instance, he was reminded to do deep breathing or drink water whenever he felt like puffing again.
When Mr Loh stubbed out for good last June, his children's asthma attacks came to a stop too. In February, the paediatrician even discharged his son from hospital care, which made him very happy.
"Actually, smokers know that they should quit for their own good," said Mr Loh.
"For me, knowing the harmful effects of environmental smoke made the difference."
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