What causes air pollution?
In Vietnam, air pollution is rising at an alarming rate, especially in big cities such as Hanoi and Ho Chi Minh City. Air pollution can result from transportation, industry, handicrafts and construction activities. According to the experts, air pollution in urban caused by traffic accounts for 70 %.
According to reports on ambient air situation for the period 2008 -2012, NO (nitrogen oxide) tends to increase in the rush hours in the morning and afternoon. The concentration of dust parameters tend to remain at high level, especially along the roads and highways with high traffic density. Dust pollution around construction sites is relatively serious and maintains at high level for long period of time during the construction period.
At residential areas located in big urban areas affected by traffic, pollution levels exceeded Vietnam Standard many times. 2011 is a recorded year of dust pollution in the entire country. Dust concentrations at almost monitoring sites around the resorts, industrial complexes exceed the standard, even some areas exceed to 3-4 times.
According to Prof. Dr. Le Huy Ba, Director of the Institute for Science, Technology and Environmental Management in Ho Chi Minh City University of Industry, every day in the city around 5 million vehicles circulating along the main road of 500 sq. kilometer of the city have made air pollution levels even more serious. Many industrial, handicraft and manufacturing facilities in the city do not equip dust and emission treatment systems.