SINGAPORE — Tekka Centre food stall owner Zaiton Bee had already been struggling with the high costs of running her business before the haze. Suffocated by the bad air now, she is considering shuttering the Muslim food stall she has been running for a decade. The 73-year-old said she would serve about 500 customers a day before the haze situation escalated. Currently, she gets only about 200 diners daily.