BEIJING - China is suffering from an increasing number of environmental accidents, mainly triggered by the rapid growth of the chemical industry in the wake of urbanization, a senior environmental official said.

Last year, 542 environmental accidents were handled across the country, statistics from the Ministry of Environmental Protection showed.

"At present, nearly 60 percent of such accidents were triggered by traffic accidents and safety accidents in the process of production," Ling Jiang, deputy director of the department of pollution prevention and control under the Ministry of Environmental Protection, told China Daily on Monday.

In a recent case in January, cadmium pollution in the upper Longjiang River posed a potential threat to the water supply in the downstream city of Liuzhou, which has 3.7 million residents.

Cadmium is a highly toxic heavy metal used in batteries, electroplating and industrial paints. Exposure can lead to fatal liver and kidney damage.

Meanwhile, the number of accidents caused by illegal discharge of waste and other pollutants is quite limited as government authorities have launched strict monitoring measures, Ling said, without giving specific statistics.

Officials said serious water shortages and pollution are now major bottlenecks to the sustainable development of the country. More than 200 million rural residents do not have access to safe drinking water, official figures showed.

To ensure water safety, 178,000 kilometers of key rivers and lakes, as well as 43,000 square meters of reservoirs, had their functions clarified - such as for drinking water and water supplies for agriculture and industry - according to the latest national plan approved by the State Council in December.

Standards on pollution discharges differ according to the water's function.

"Water pollution is very serious in China now. Only about 46 percent of the 178,000 kilometers of key rivers and lakes monitored by the ministry are up to standard on quality," Chen Mingzhong, an official in the Ministry of Water Resources, said on Monday.

Nearly 80 percent of the key rivers and reservoirs with specific usage functions are targeted to reach the standard by 2020, and all will meet the standard by 2030, according to the plan. "Government authorities at all levels are accountable for the task, and they will surely receive strict punishment for areas that exceed their standards on pollution discharge," he said.