A series of pollution scandals in the first part of the year had many observers predicting the environment would be a big topic at China's annual political conclave, currently underway in Beijing. Those expectations rose even higher this week after smog blanketed the proceedings at the Great Hall of the People and thousands of dead pigs were found floating in the Huangpu River near Shanghai.

Apparently Wu Xiaoqing, China's vice minister of environmental protection, missed the memo.

"Tightly scripted" might be an understatement in describing a Ministry of Environment Protection news conference, presided over by Mr. Wu, held on the sidelines of the National People's Congress on Friday.

With levels of particulate pollution soaring outside, Mr. Wu was selective in calling on reporters. Among those chosen was a journalist from a state-backed magazine, who noted concern in the Maldives over rising sea levels, then asked how China, as a large and developing country, would contribute to "the construction of ecological civilization."

Mr. Wu's answer was unmemorable, but the question underscored how cautious environmental authorities have become as the public grows increasingly aggressive in openly challenging the government over China's environment.