STUDENTS who travel by school bus are more likely to end up coughing and spluttering in class than those who walk or use other means of transport.
This is the conclusion drawn by researchers at Polytechnic University (理工大學). They say the amount of dangerous pollutants found in some of the buses is more than double the standard set by the World Health Organisation.
The researchers also found that in addition to breathing in large amounts of particulate matter, children are also exposed to high levels of carbon dioxide in some of their classrooms.
The researchers tracked 310 students,aged between 11 and 12, at 12 primary schools. They monitored the air pollution levels along the routes the students travel to class from 2011 to this year. Of the 310 students, 24 percent took the school bus, 48 percent walked and the rest used other means of transport.
The 12 schools were situated on Hong Kong Island, Kowloon East, Tsing Yi (青衣),Sha Tau Kok (沙頭角), Yuen Long (元朗), Ta Kwu Ling (打鼓嶺) and Tuen Mun (屯門).
On arriving at school, students were asked to blow into a device called a spirometer, which measures the volume and flow of air that is inhaled and exhaled.
Professor Hung Wing-tat(熊永達) said those arriving by school bus had the worst lung function when compared with others.