By Stuart Leavenworth, McClatchy Foreign Staff

BEIJING — China’s capital region remained swathed Monday in a cloud of choking smog, prompting a rise in hospital visits and sales of indoor air purifiers and reports of rare industry shutdowns.

China’s Ministry of Environmental Protection on Sunday dispatched inspection teams to fine and shut down polluting industries in the region, and there were reports that regulators had idled a major concrete kiln and other factories outside Beijing.

But the shutdowns did little to end a four-day bout of heavy particulate smog. Nor are they likely to ameliorate skepticism among residents and outside experts about China’s commitment to environmental protection.

Alex Wang, who teaches law at the University of California, Los Angeles, said China had extensive environmental laws on the books and an increasingly sophisticated ability to monitor sources of smog.

“The problem is not a lack of knowledge about pollution sources,” said Wang, who previously headed the Beijing office of the Natural Resources Defense Council. “Rather, the problem is that environmental regulators lack sufficient authority to deter polluters from violating the law.”

Beijing’s 5 million vehicles are an increasing contributor to the city’s air pollution, but the biggest sources are thought to be industries, smelters and utilities outside the city that use coal as a power source.

On Beijing’s worst days, the smell of coal soot hangs heavy in the air. At 6 p.m. Monday, the air monitor at the U.S. Embassy in Beijing reported that levels of so-called PM 2.5 contaminants — fine particles produced by coal burning that pose the worst risk to human health — had topped 400 micrograms per cubic meter. That’s about 16 times higher than the World Health Organization deems safe, and about five times higher than recent soot levels in Los Angeles.

Beijing’s recent smog bout started more than a week ago and intensified Friday, when authorities issued a code orange alert, reserved for heavy smog that lasts for at least three consecutive days. It was the first time authorities had issued such an alert since they established the color-code system — with red reserved for the absolute worst conditions — last October.

While Beijing residents are accustomed to periods of filthy air every winter, the latest pall is testing the patience of many in the city.

“Beijing’s air is so bad,” one Beijing blogger, Ming Hui, wrote on Sina Weibo, China’s version of Twitter. “What are the relevant government departments doing? … Should enterprises and businesses that emit pollutants buy air purifiers for the people?”

According to a report Sunday in the Beijing Morning Post, the number of people going to the respiratory wards of various hospitals in the city has increased 20 percent to 50 percent since Friday. On the street Monday, pedestrians outfitted in masks were far more visible than the week before, although a large number — mainly men — wore no protection and could be seen enjoying the outdoors by lighting up cigarettes.

Health-minded Beijingers have good reason to be skeptical about continuing official pledges to protect their lungs. While China has shown that it can clamp down on emissions — it did during the 2008 Olympics in Beijing — the government’s ambitious industrial growth targets, powered by the world’s largest consumption of coal, trump its environmental goals. And far too often, Wang and other experts say, the government doesn’t want to risk blowback from industries or even citizens by enforcing environmental laws.

Photo: KiRin Chen via Flickr