BEIJING — Beijing and other parts of northern China were stung by hazardous air pollution levels Thursday as strong winds blew a sandstorm through the region.

Air in the capital turned a yellowish hue as sand from China's arid northwest blew in, turning the sky into a noxious soup of smog and dust.

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At 6 a.m. local time, the U.S. Embassy's air quality index showed a reading of 516 for particles less than 2.5 micrometers in diameter. Known as PM2.5, such particles are considered particularly dangerous because they can lodge deeply in the lungs. On the American air pollution index, the air at that time and throughout much of the morning was classified as "beyond index."

 

The developers of the U.S Embassy's air monitoring station had planned for an index capped at 500. The World Health Organization suggests that 24-hour exposure to PM2.5 should be limited to levels of 25 on that scale.

Beijing's municipal government issued a yellow-haze warning late Wednesday while state media urged citizens to stay indoors or to take precautions such as donning face masks before venturing outside.

Across northern China in provinces including Hebei, Hubei, Jiangsu and Inner Mongolia, air monitoring stations recorded readings over 500, and visibility across the region was severely curtailed. In some places visibility was below 3,200 feet, leading to highway closures, suspension of high-speed train services and the cancellation of flights from Beijing International Airport.

By mid-afternoon, pollution levels had fallen and strong winds had pushed much of the remaining cloud cover from the capital.

Geographically close to the Gobi Desert, Beijing and other northern cities are particularly susceptible to sandstorms such as Thursday's. Sandstorms are prevalent in late winter and spring as melting frost frees sand and strong winds kick it up and push it eastward.

The start of 2013 has brought chronic bad air to much of China. In January, air pollution readings were so bad that they were compared to living in an airport smoking lounge. That comparison was underscored by record high levels of PM2.5 on Jan. 12, when readings topped out at 755 on the air quality index.

Frustration over China's continued pollution problems popped up across Chinese social media. But irritation over the long-brewing issue was perhaps best summed up by a viral photo originally posted on popular Web portal QQ.com of an unhappy looking Yao Ming, grimacing at the Beijing sky.

Yao, the former NBA All-Star and current member of a Communist Party advisory board known as the China People's Political Consultative Conference, is currently in Beijing in the lead-up to next month's National People's Congress.

The congress will mark the final step in China's once-in-a-decade leadership change as party heads Xi Jinping and Le Keqiang formally take over as China's president and prime minister, respectively.

Since taking over China's ruling Communist Party late last year, the new leaders have spoken repeatedly about improving the mainland's environment.

Many China watchers believe that China's environmental degradation -- underscored by severe air pollution, contaminated soil and dirty waterways -- will be a focal point during the congress.

This story was originally published on Thu Feb 28, 2013 6:46 AM EST

BEIJING — Air quality in Beijing was the "worst on record" on Saturday and Sunday, according to environmentalists, with pollution 30-45 times above the recommended safety levels.

With a thick smog wrapping the Chinese capital since Friday, the city's pollution monitoring center warned the city's 20 million residents to stay indoors.

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Data posted on Sunday by the monitoring center showed particulate matter measuring less than 2.5 micrometers in diameter (PM2.5) had reached more than 600 micrograms per square metre at some monitoring stations in Beijing, and was as high as 900 on Saturday evening.

The recommended daily level for PM2.5 is 20, according to the World Health Organisation. Such pollution has been identified as a major cause of asthma and respiratory diseases.

"This is really the worst on record not only from the official data but also from the monitoring data from the U.S. embassy — some areas in (neighboring) Hebei province are even worst than Beijing," said Zhou Rong, climate and energy campaigner at Greenpeace.

The Beijing Municipal Environmental Monitoring Center said heavy pollution had been trapped by an area of low pressure, making it harder to disperse, and the conditions were likely to last another two days.

Related: Beijing's pollution could cut 5 years off life span

Pollution has been identified as one of the biggest challenges facing China's leaders, with outgoing president Hu Jintao saying during his address to the Communist Party Congress last November that the country needed to "reverse the trend of ecological deterioration and build a beautiful China."

China said at the end of last year that it would begin releasing hourly pollution data for its biggest cities.

Beijing has already committed to a timetable to improve air quality in the city, and has relocated most of its heavy industry, but surrounding regions have not made the same commitments, said Zhou.

"For Beijing, cleaning up will take a whole generation but other regions don't even have any targets to cut coal burning. I bet the pollution here is mainly from those surrounding regions." 

 

Copyright 2013 Thomson Reuters. Click for restrictions.

QIDONG, China -- Angry demonstrators occupied a government office in eastern China on Saturday, destroying computers and overturning cars in a violent protest against an industrial waste pipeline they said would poison their coastal waters.

Hours later, the mayor of the city where the pipeline was to have originated said the project was being cancelled, Reuters reported.

The demonstration was the latest in a string of protests sparked by fears of environmental degradation and highlights the social tensions the government in Beijing faces as it approaches a leadership transition this year.

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Thousands of protesters marched through the coastal city of Qidong, roughly one hour north of Shanghai by car, shouting slogans against the planned pipeline that would empty waste from a paper factory in nearby Nantong into the sea.

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Demonstrators rejected the government's stand that waste from the factory would not pollute the coastal waters.

"The government says the waste will not pollute the sea, but if that's true, then why don't they dump it into Yangtze River?" said Lu Shuai, a 25-year-old protester who works in logistics.

"It is because if they dump it into the river, it will have an impact on people in Shanghai and people in Shanghai will oppose it."

The state-run Global Times newspaper quoted local residents who said the sewage discharge from the pipeline was expected to be as much as 150,000 tons per day, according to the AFP news agency.

Cars overturned, cops beaten
Several protesters entered the city government's main building and were seen smashing computers, overturning desks and throwing documents out the windows to loud cheers from the crowd.

China begins to admit 'fog' is really smog

An AFP photographer described the scene, saying demonstrators seized bottles of liquor and wine from the offices, along with cartons of cigarettes -- all of which Chinese officials frequently receive as bribes.

Reuters witnessed five cars and one minibus being overturned. Over 1,000 police -- some paramilitary -- guarded the city government office compound in lines.

At least two police officers were dragged into the crowd at the government office and punched and beaten enough to make them bleed.

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According to the AFP, searches including "Qidong" on China's popular microblogging site Sina Weibo were blocked Saturday. Sina Weibo has over 250 million subscribers.

Earlier posts on Weibo and on Twitter indicated that the protesters had stripped the clothes off the local party secretary, but these reports could not be immediately verified.

On Friday, in an effort to stave off the protest, the Qidong city government announced it would suspend the project for further research.

But many protesters said on Saturday that postponement was not enough.

"If the government really wanted to stop this project, they should have done it right from the beginning. At this point they are too late," said Xi Feng, a 17-year-old protester.

Local officials took steps to ward off the demonstration and residents received text messages and letters warning that any public demonstration would be illegal.

The reversal came Saturday afternoon, when Nantong Mayor Zhang Guohua announced in a statement that the city would terminate the project proposed by a Japanese-owned paper factory in its jurisdiction. 

Rising discontent
Environmental worries have stoked calls for expanded rights for citizens and greater consultation in the tightly controlled one-party state.

The outpouring of public anger is emblematic of the rising discontent facing Chinese leaders, who are obsessed with maintaining stability and struggling to balance growth with rising public anger over environmental threats.

The protest followed similar demonstrations against projects the Sichuan town of Shifang earlier this month and in the cities of Dalian in the northeast and Haimen in southern Guangdong province in the past year.

China tells US Embassy to stop reporting Beijing pollution

In Shifang, the government halted construction of a copper refinery following protests by residents that it would poison them. It also freed most of the people who were detained after a clash with police.

The leadership has vowed to clean up China's skies and waterways and increasingly tried to appear responsive to complaints about pollution. But environmental disputes pit citizens against local officials whose aim is to lure fresh investment and revenue into their areas.

Behind The Wall: Full NBC News coverage from China
Pictures from China on NBCNews.com's PhotoBlog

NBC News researcher Tianzhou Ye, Reuters and The Associated Press contributed to this report.

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Updated at 10:52 a.m. ET: While Shifang city government officials have announced that construction on the refinery will be halted, some residents have continued to protest in the streets to demand the release of some protesters detained during the protests including an unknown number of college students from a nearby aviation academy.

BEIJING -- Construction of a copper factory in central China has been halted, an official said Tuesday, after days of angry protests over fears of pollution culminated in clashes that saw riot police fire stun grenades and tear gas to break up a crowd of thousands.

Residents of the town of Shifang, Sichuan province, have been slowly gathering around a local city government office since Saturday, the day after a foundation-laying ceremony put on by Sichuan Hongda – a conglomerate specializing in minerals, real estate and finance – to celebrate the first phase of construction on the $1.64 billion proposed molybdenum-copper alloy refinery nearby.

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When -- or now if -- completed, the refinery could generate an estimated $8 billion a year.

According to local Sichuan newspaper reports, the protest started with around a dozen people, but by Sunday it had grown as fellow residents and high school students joined them.

By Monday, there was a crowd of thousands, a police officer on duty there told the Chinese newspaper, Global Times. However, the South China Morning Post reported the figure was in the tens of thousands. 

By early Monday afternoon, tensions had escalated and protesters attempted to occupy the city government offices, forcing their way past police inside where they reportedly threw bricks through windows and destroyed offices there. Riot police were brought in to restore order, firing tear gas and stun grenades to break up the crowd.  

Some 13 injuries were initially reported by official state media, but witnesses on the ground reported far more wounded.

As of late Tuesday afternoon, protesters were reportedly still on the streets of Shifang, effectively locked in a standoff.

Local government officials were facing pressure from provincial-level and central government leaders to stifle social unrest.

'No longer suitable for living'
A protester surnamed Wang told NBC News that their numbers had thinned out as the city boosted its police presence.

“The two sides are just standing, facing each other,” Wang said. “There are a lot of police and the roads are blocked.”

“Yesterday, the protesters were all concentrated in front of the government building,” said another protester who requested anonymity. “But today, the police have blocked all the roads around the government building so people cannot concentrate in one area and are scattered everywhere… I am not sure how many people there are, but fewer than yesterday."

Bathed in smog: Beijing's pollution could cut 5 years off lifespan, expert says

Asked what he would do if construction went ahead on the refinery, the man responded, “As far as I’m concerned, I have settled here, but this place will be no longer suitable for living.” 

“If my economic situation and other conditions meet, I will definitely move away," he added.

Concerns over the pollution created by the alloy refineries that dot China’s resource-rich regions have grown in recent years as China’s economy develops and its people become better educated about the effects of industrial waste on human health.

“I think in general smelters are heavily polluting facilities no matter what, they smelt,” said Ma Tianjie, a Greenpeace campaigner in China specializing in heavy metal waste. “We have seen a lot of cases with heavy metal smelters where there is substantial release of all kinds of toxic pollutants.”

Those pollutants are released into the air through smoke and into the nearby area's ground and water supplies through the highly toxic slag waste that is a byproduct of a refinery’s production phase. Arsenic, an element that can cause severe kidney and liver problems in humans, is often found in worrying levels in this slag.

As these health concerns have become increasingly more public, so too has opposition to these refineries in urban areas.

While companies and local governments have up until now been largely able to duck growing NIMBY-ism in urban centers around China, officials here are increasingly finding themselves accountable for the environmental legacy of these lucrative, but highly polluting industries. 

A legacy that Ma warns can stay with a population for a long time. “Generally the smelters will leave a quite heavy legacy to the local community” he warned, “even decades after the facilities leave.”

Construction suspended
The mass public protest in Shifang has for now, had its desired effect: Late Tuesday afternoon, Shifang’s local Communist Party chief, Li Chengjin, announced through the government’s Weibo microblog feed that the government was halting construction of the refinery and would no longer allow it to go ahead.

“It’s definitely a piece of good news that construction is being halted, this is absolutely what we wanted,” said Wang upon hearing the news of the government’s decision to halt construction.

However, similar recent cases suggest that such success could just be temporary. Last summer, thousands of residents of the northeastern port city of Dalian took to the streets to protest a chemical factory after a dike broke following a storm, potentially exposing the city to the threat of a toxic spill.

Local officials were successful in keeping the crowd peaceful and eventually broke up the protests when they emphatically pledged to halt production at the factory and have it moved out of the city.

But production resumed soon after, though local officials there have stressed since then that the factory was still slated to be moved.

NBC News’ Horace Lu contributed to this report.

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BEIJING — Earlier this month, a U.S. study on the economic impact of China’s air pollution was released with little fanfare. Maybe it was because of the series of successive “blue sky” days we were enjoying in the Chinese capital, thanks to the gusty winds blowing down from Mongolia. 

The study, which was conducted by researchers at the MIT Joint Program on the Science and Policy of Global Change, breaks down costs that result from the health impacts from ozone and particulate matter, which typically lead to respiratory and cardiovascular diseases.

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The conclusion? “[D]espite improvements in overall air quality,” the cost of air pollution (as in lost economic productivity growth) in China has mushroomed from $22 billion in 1975 to $112 billion in 1995. But for at least one pair of 29-year old software engineers in Beijing, air pollution has actually meant greater economic productivity and a business opportunity.

A killer app
Wang Jun and Zhang Bin each moved to Beijing in 2001 to attend college.  Zhang, a Fujian native, was a math major at Beijing University while Wang left Inner Mongolia to study traffic infrastructure at Jiaotong University.

They met at a high-tech company, where for three years they worked together. Last year, they decided to strike out on their own and set up Fresh Ideas Studio.

“The primary aim … is creating mobile apps for solving practical problems in our daily lives,” Wang said, on a blustery (but sunny) afternoon at a coffee shop.

Last year saw some of the worst air pollution in Beijing since the 2008 Summer Olympics, spurring intense discussion among Chinese residents, teeth-gnashing among Western expats, and a near-diplomatic spat between the U.S. and China over fine particulate matter in the air known as PM2.5 that can wreak havoc on the respiratory system.

“Recently, the media and Weibo [a popular Chinese microblog like Twitter] users are very concerned about air quality, especially in Beijing,” Wang said.

In particular, there was a lot of online chatter about @Beijing Air, the U.S. embassy Twitter account that posts hourly Air Quality Index(AQI) data. 

The readings come from an air quality monitor that sits on top of the embassy in downtown Beijing, and they differ sharply from the daily results posted by the Ministry of Environmental Protection (MEP).

AQI values on @BeijingAir range from 0 to 500.  A “good” AQI  is 0 to 50 or what the Chinese call a “blue sky” day.  Unfortunately, many days in 2011 qualified as “unhealthy” to “hazardous.”  But on some of those same days, MEP data maintained the levels were “good” or “moderate.”  (The Chinese, in fact, claim there were 286 "blue sky" days in 2011.)

“The [Beijing] government says that nearly 80 percent of the days in the last two years met at least the Chinese standard and therefore had good or even excellent air quality,” Steve Andrews, an environmental consultant who has analyzed the @BeijingAir data, said. “While when we look at the U.S. Embassy data … over 80 percent days exceeded what would be considered healthy air quality and more days were hazardous than good.”

Andrews said that Beijing's pollution levels were "six or seven times higher than the U.S.'s most polluted city." "Air pollution at these levels likely shortens life expectancy by about five years," he added.

The discrepancy was due to the fact the U.S. embassy monitor includes PM2.5, a fine particulate matter measuring 2.5 micrometers in diameter that, according to the EPA, “pose the greatest health risks [and] can lodge deeply into the lungs.”

The Chinese data, however, only measured the much coarser PM10 particles.

“I’m a Twitter user and saw many Tweets about [@BeijingAir],” Zhang said. “Many Weibo users reposted the data, too.”

The software developers decided to try creating a smartphone application that based itself on the @BeijingAir data.

“Sometimes we can tell there’s a gap between what we feel and the data from the government,” Wang said.  “This is probably why many prefer the data provided by the U.S. embassy.”

In November, they released a 1.0 version, available only in Chinese and which came with simple but appealing graphics.  On good AQI days, the screen background was light and featured a hiking boot, indicating it was time to be outdoors. On bad AQI days, the screen background turned dark, an X marked the boot, and a person’s face wrapped in a mask would pop up.

There were iOS and Android versions of the app. Within weeks, it had been downloaded 80,000 times. At least half of those users checked the app regularly, according to Wang. 

Pollution 'ignored' in past
Under popular pressure that has been building since last year, Chinese environment authorities in Beijing have agreed to publish PM2.5 data. But they maintain the air quality has improved steadily in recent years. 

“We may have had bad pollution in the past, but people probably didn’t pay too much attention to it before so it was just ignored,” said An Xinxin, who works in the Automatic Monitoring Office at the Beijing Environmental Protection Monitoring Center. 

The Center relies on anywhere from 30 to 40 monitoring stations. “Almost every district and county in Beijing has its own station,” explained An. “So citizens in every district and county can know what the pollution in their own area is like.”

Like many of his colleagues at the municipal level, An pointed out that the U.S. embassy only uses one monitor. “[It] can only represent one spot at a certain time. Their spot might be very close to the road where there is a lot of vehicle exhaust, which causes a high level of PM2.5,” he said. “Our statistics are an average of Beijing as a whole, not just one spot.”

Zhang has lived in Beijing for more than ten years, but he said he’s not sure whether the air quality has improved or not. “I don’t know if it’s because now I pay more attention [because of the media and online discussion], or if it’s because the air quality has worsened,” he said. 

But he and Wang dreamed up the idea of incorporating both the Chinese and American data streams into their app.

On Monday this week, they introduced a 2.0 version that not only posts real-time data from the U.S. embassy in Beijing and U.S. consulates around China, it also includes data from the Chinese Ministry of Environment’s monitoring centers in 120 cities across the country.

Also available in English, the app has been downloaded nearly 5,000 times.

“We thought it was good to include both. In some cities, users might want alternative information,” Wang said. “If there were a third source for air pollution data, we’d probably include it in the app, too.”

They might also want to add Hong Kong to their list of cities.

This month, a local nongovernmental group said Hong Kong’s air is 20 per cent more deadly than the air in mainland China. 

Using data from Hong Kong’s own government and the World Health Organization, the Clean Air Network ranked Hong Kong ahead of mainland China, India, Vietnam, and Bangladesh for its high air pollution mortality rates.

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With additional reporting from Bo Gu and Ting Zhao.