Nitrogen dioxide levels around some Hong Kong parks and schools ‘concerning’, Greenpeace survey finds, but scientists say results may not be as alarming as they look

Concentrations of a major air pollutant can reach “concerning” levels around public parks and primary schools in Hong Kong, a survey by a green group has found.But two scientists, who both endorsed the need to control the city’s roadside air pollutants, cautioned against the survey’s methodology, saying the findings might not be as alarming as they sound.The Greenpeace air quality survey measured the level of nitrogen dioxide, a major pollutant released from vehicle exhausts and electricity…