China has deployed 11 highly trained professionals to sniff out foul gases and other dangerous chemicals in the air of what is rapidly becoming one of the most polluted countries.

The State Environmental Protection Key Laboratory for Controlling Evil Odours and Pollution in the northern city of Tianjin had put its students on a rigorous – if somewhat unpleasant – course, which involved sniffing 25 bottles of liquids with various odours.

“We have to stay in a lab smelling those awful gases repeatedly,” Liu Jingcai, deputy director of the bureau, said.

The 11 newly fledged experts, all working for the Panyu Environmental Protection Bureau in the southern Guangdong province, did not need to have any special gifts. “We are not looking for experts to invent a new fragrance, so any adult with a normal nose can take part,” an official toldThe Times: After training, the human nose can become more sensitive than even the most sophisticated equipment. Mr Liu said: “Our equipment can analyse the density of a particular gas accurately but with mixed gases they are not reliable . . . and it cannot tell the effects on humans. Now we can differentiate between hundreds of smells.”

The Panyu team will complement scientific equipment to help to bring pollution violators to account. Their contracts, however, are for only three years because the sense of smell deteriorates with age. Human sniffers were not necessary in Beijing this week to detect the highest pollution level in any of China’s 47 main cities for three successive days.

A dull, yellowish light glimmers over a city so engulfed by haze that the sun cannot penetrate. The air is brown with filthy fumes and visibility is reduced to a few hundred yards. Residents describe a stinging of the eyes and grit between the teeth.

The air pollution index for Beijing showed the level yesterday at 151 on a scale by which a reading under 50 is excellent and over 300 is too serious to allow for outdoor activities. The reading reached 200 one day last week.

New figures by Dutch scientists also show that for the first time China has overtaken the United States as the world’s top emitter of carbon dioxide, an odourless gas blamed for global warming.

Nose for truth

The Institut Supérieur International du Parfum, in France, trains the world’s top perfumers to distinguish smells. Its graduates are taught to work with hundreds of ingredients

Robert Parker, the US wine critic, is considered one of the most influential tasters in the world, publishing a ranking of wines according to a 100-point scale that can make or break a vineyard. So concerned is he that he may lose his sense of smell that he has insured his nose for $1 million (£500,000)

In 2004 the Nobel Prize in Physiology or Medicine went to two scientists who helped to unravel the mystery of smell – which the Nobel Prize Committee called “the most enigmatic of our senses”. They discovered that humans distinguish 10,000 different odours using only a few hundred receptors Source:

Agencies, Nobel Institute

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