Mixing of particulates and moisture is blamed for a rise in respiratory illnesses Guangzhou doctors and residents are blaming a brownish-yellow shroud of particulates and moisture that has hung over the city for more than a week for an increase in respiratory diseases especially among children and the elderly. 'Air pollution is one of the reasons for the rise in cases of bronchitis and other respiratory diseases, especially among children and older people,' said Guangdong Health Department spokesman Feng Shaomin . 'The government has allocated 300 million yuan to expand the Guangzhou Institute of Respiratory Diseases but there has to be a multi-departmental approach to the problem,' he said. A 74-year-old retired man said he had not experienced such bad air quality in the spring before. 'I feel oppressed ... I don't feel alert. It's because of the cars - the density of cars in this city is too high,' he said. Since last year, weather experts found a new phenomenon they have seen in only one other place - Beijing - when airborne particulates expand upon contact with moisture in fog. The phenomenon, which they call 'polluted fog', has been brought under control in the capital but is drawing air pollution scholars including the Hong Kong University of Science and Technology's Alexis Lau Kai-hon to the Pearl River Delta to conduct studies. Wu Dui , an academic who has studied air pollution in the Pearl River Delta since 1987, said: 'In terms of visibility, our problem is more severe than in Los Angeles. Sometimes, visibility is not even 1km.' There had been reports of a higher incidence of respiratory diseases by Guangzhou hospitals but while nobody had died as a direct or indirect result of smog, as in Los Angeles or London, the harmful effect could not be ruled out, Professor Wu said. The professor is concerned that the particulates could enter the bloodstream and harm the body. The Guangzhou Environmental Protection Bureau was not available for comment, but a bureau executive played down the severity of the smog, saying they disagreed with the weather experts and that haze and pollution were not the same thing. In the past few years, the bureau reported that Guangzhou's air quality had remained good while acknowledging that particulate levels had risen. Last month there were 12 days when visibility fell as low as 1.62km, while last year there were 144 days of poor visibility as a result of the smog. But no warnings have been issued to the public to avoid strenuous physical activities outdoors on days when there is poor air quality. In fact, the Air Pollution Index (API) reading yesterday was 91, which means good air quality, while Baiyun Mountain remained hidden in the haze. An environmental expert said mainland API readings did not take into account all the parameters that Hong Kong did. On Monday, the municipal government allocated 200 million yuan to build three air-quality monitoring networks over the next three years to provide data on dust, haze and fog, which have not previously been recorded, to the environmental protection bureau. '[The spending] is unprecedented ... this was unthinkable in the past,' Professor Wu said. He is expecting the government to announce other measures to prevent further deterioration in air quality such as more stringent emission controls, use of cleaner fuels and a total ban on motorcycles. Guangzhou's latest air pollution problem, which experts believe to have been triggered by emissions - from vehicles, factories and power plants - combined with weather conditions, is particularly serious because the phenomenon is compounding old problems. Guangzhou's first taste of bad air came in the 1980s when dust caused 180 low-visibility days a year but this was lowered to 100 days in 1989 after preventive measures were taken. But in the early 1990s, sulphur dioxide emissions caused the numbers to rise, peaking at 210 low-visibility days in 1997 before measures were taken and the number fell to 60 in 2000. The relief was short-lived as by 2002, comprehensive air pollution set in and the number rose again. Professor Wu's research showed Guangzhou's air quality is the worst of all mainland cities and is bad all year round unlike in northern cities where the problem is confined to winter when coal is burned for heating. Although Guangzhou is taking the right steps to clean its air, Professor Wu says collective action needs to be taken by all Pearl River Delta cities. Satellite maps show the centre of the pollution to be in Foshan where kilns release enormous amounts of particulates while Dongguan , another big culprit, is spared by winds that blow the particulates to Guangzhou and Foshan. 'Small kilns still line the highway from Foshan to Yangjiang . They have to be shut down or merged to form bigger kilns,' he said. Professor Wu said Guangzhou needed more sophisticated monitoring to allow more flexibility in limiting emissions, he said. On days when there was wind to help disperse particulates, factories could be allowed to emit more, he said. Guangzhou was already spending 2 per cent of its gross domestic product on an environmental clean-up, but the money would be wasted if there was no proper enforcement of anti-pollution measures, he said. Professor Wu said Guangzhhou had adopted European emission standards but trucks and buses were still belching black smoke. 'Unlike in Beijing, there is nobody you can call to go after these polluters,' the expert said.