A SENIOR American official has raised serious concerns about pollution in China, suggesting it could have major implications for the region as the mainland races ahead with industrial reforms. US Under-secretary of State for Global Affairs, Timothy Wirth, who was in Beijing last week on an official visit, said what happened in China had consequences that reach far beyond its own borders. The United States is particularly concerned about China's reliance on what he called 'very dirty brown coal' for an estimated 75 per cent of its energy needs. 'As the Chinese are generating electricity for heat here in China, they are also generating greenhouse-forcing gasses, and we all get warm together,' he said. 'When China sneezes most of the rest of the world could potentially catch cold.' While the long-term build-up of such gases threatens to cause climatic changes on a global and potentially cataclysmic scale, Hong Kong faces a more immediate hazard: China's plan to build a coal-fired power station on the eastern shore of Mirs Bay. The proposed 2,460-megawatt Eastern Shenzhen power station is being backed by a subsidiary of Gordon Wu Ying-sheung's Hopewell Holdings, which says it has already received preliminary approval from China's State Planning Commission. But it is not yet clear what pollution-control standards the plant will employ to limit its discharge of noxious sulphur dioxide. Experts say that for six months each year, the prevailing wind will carry any pollution produced at the site directly towards Hong Kong. The territory now requires all new coal plants to install desulphurisation equipment. According to one Western environmental specialist, however, such equipment adds substantially to the cost of a plant and is especially prohibitive in China because it must be imported. Very few Chinese plants employ it, she added. But Zhao Jianjing, a power analyst for the World Bank in Beijing, said plants operating in southeastern China do not necessarily need to use desulphurisation equipment because the coal generally used in the area has a very low sulphur content. According to statistics released by China's Ministry of Power, the efficiency rating of the nation's major coal-burning power plants has jumped by 10 percentage points since 1988, rising to 'the level of North American countries'. As China's economy rapidly grows there has been a tremendous increase in the demand for energy, and Guangdong's appetite has increased faster than that of any other province. During the first six months of 1994, Guangdong used nearly 35 per cent more energy than it did over the same period last year. However, last summer the Sunday Morning Post published claims from environmentalists that pollution from China alone had helped contribute to the deaths of at least 8,440 people in Hong Kong.