MORE than one million people in the Chinese city of Handan awoke last week to the alarming news that an essential source of their drinking water, the Zhouzhang River, had been dangerously contaminated by a 39-ton chemical spill in the nearby city of Changzhi. What made the news even more shocking was that the leak, from a factory pipe, had started at least five days earlier but had been kept secret by government officials, who allowed millions of their neighbors to keep drinking.