<p>Schools, expressways and an airport remained closed as thick polluted smog continues to envelope a northeastern Chinese city for the second day today.<br /><br /></p>.<p>Meteorological authorities in Harbin city issued a red alert for the fog, with visibility in some areas reduced to less than 20 metres.<br /><br />Kindergartens, primary and junior middle schools were ordered to suspend classes for a second day in Harbin, the provincial capital of Heilongjiang Province.<br /><br />The Harbin Taiping International Airport has been shut down since Monday.<br /><br />All expressways in Heilongjiang remained closed today, state-run Xinhua news agency reported.<br /><br />The severe smog continued to shroud other major cities such as Changchun, capital of Jilin Province and Shenyang, capital of Liaoning Province. Meteorological authorities in the two provinces also issued a red alert for the fog.<br /><br />Traffic control has been implemented since yesterday evening for the section of the Beijing-Harbin expressway that passes through Jilin Province.<br /><br />The heavy fog began to hit the vast northeastern region on Sunday.<br /><br />"The impact of air pollution on people will be gradual. There won't be a sudden outbreak of symptoms, but normally three to five days after the smoggy weather occurs, there is a peak in the number of people seeing doctors," said Deng Ying, a doctor at the Second Affiliated Hospital of Harbin Medical University.<br /><br />Meanwhile, the Ministry of Environmental Protection released air quality data of 74 cities in September and the three-month period from July to September.<br /><br />The ministry listed the 10 cities with the worst air quality in the third quarter of the year: Xingtai, Shijiazhuang, Tangshan, Handan, Hengshui, Baoding, and Langfang in northern Hebei Province; Jinan in eastern Shandong Province; the municipality of Tianjin; and Zhengzhou in central Henan Province.</p>
<p>Schools, expressways and an airport remained closed as thick polluted smog continues to envelope a northeastern Chinese city for the second day today.<br /><br /></p>.<p>Meteorological authorities in Harbin city issued a red alert for the fog, with visibility in some areas reduced to less than 20 metres.<br /><br />Kindergartens, primary and junior middle schools were ordered to suspend classes for a second day in Harbin, the provincial capital of Heilongjiang Province.<br /><br />The Harbin Taiping International Airport has been shut down since Monday.<br /><br />All expressways in Heilongjiang remained closed today, state-run Xinhua news agency reported.<br /><br />The severe smog continued to shroud other major cities such as Changchun, capital of Jilin Province and Shenyang, capital of Liaoning Province. Meteorological authorities in the two provinces also issued a red alert for the fog.<br /><br />Traffic control has been implemented since yesterday evening for the section of the Beijing-Harbin expressway that passes through Jilin Province.<br /><br />The heavy fog began to hit the vast northeastern region on Sunday.<br /><br />"The impact of air pollution on people will be gradual. There won't be a sudden outbreak of symptoms, but normally three to five days after the smoggy weather occurs, there is a peak in the number of people seeing doctors," said Deng Ying, a doctor at the Second Affiliated Hospital of Harbin Medical University.<br /><br />Meanwhile, the Ministry of Environmental Protection released air quality data of 74 cities in September and the three-month period from July to September.<br /><br />The ministry listed the 10 cities with the worst air quality in the third quarter of the year: Xingtai, Shijiazhuang, Tangshan, Handan, Hengshui, Baoding, and Langfang in northern Hebei Province; Jinan in eastern Shandong Province; the municipality of Tianjin; and Zhengzhou in central Henan Province.</p>