Beijing authorities said they had met their target of "blue sky" days for 2011, amid growing public criticism that officials are underplaying the pollution problem in the Chinese capital.
Japanese workers tackling the Herculean task of clearing millions of tonnes of debris from last month's earthquake and tsunami also face health risks from asbestos and dioxins.
Millions of Chinese went online Tuesday to vent their anger over the thick smog that has blanketed Beijing in recent days, raising health fears and causing hundreds of flights to be cancelled.
Beijing's government on Friday bowed to a vocal online campaign for a change in the way air quality is measured in the Chinese capital, one of the world's most polluted cities.
Every two minutes on the bus ride through the ghost towns surrounding Japan's Fukushima Daiichi nuclear plant, a company guide in a white protective suit holds up a display showing the radiation level. And it is rising.
China has cleaned up its air before but experts say that if it wants to avoid the kind of smog that choked the country this week, it must overhaul an economy fuelled by heavily polluting coal and car use.
Authorities in Delhi on Monday closed schools, halted construction work and shut down a major power plant after days of choking smog led to warnings of a health "emergency" in the world's most polluted capital.
Two-thirds of high-street garments tested in a study by Greenpeace contained potentially harmful chemicals, the group said Tuesday, highlighting the findings with a "toxic" fashion show in Beijing.
Beauty startup Foreo is launching a "UFO" to make salon-style face mask treatments as much a part of people's days as brushing teeth.
Schools in the Chinese capital kept students indoors and parents brought their kids to hospitals with breathing ailments Tuesday as Beijing grappled with extremely severe air pollution for the fifth straight day.