Air pollution kills 1600 Hong Kong people each year. As China's economy booms, pollution from factories in neighboring Guangdong Province is drifting across to Hong Kong, mixing with the emissions of a growing number of cars and driving smog levels to new records. The Hong Kong government is spending an estimated 399.6 million Hong Kong dollars, or US$51.5 million, in the year ending March on enforcement of air pollution controls. China, with seven of the world's 10 most polluted cities, has spent 280 billion yuan, or US$34.6 billion, in the past five years to counter air pollution, according to the government's 10th Five-Year Plan for Environmental Protection and still the air quality is deteriorating by the day.