Human sniffers help identify toxic tracks

At a laboratory in Wuhan, Hubei province, five certified odor identifiers - people with sensitive noses - were assigned a special task. Each of them, wearing a white gown, opened a bottle containing a 20-gram sample of synthetic running track material, and inhaled slowly for five seconds. Then they wrote down their results.

The sniffers, who are among the first such professionals in Wuhan, were testing whether the plastic, planned for use in a running track installation at a primary school, measured up to environmental standards. Another technician will give the samples a final score based on the scores given by the sniffers.

"It is very difficult to test products made of complex synthetic materials, such as plastic tracks, by physical or chemical instruments because most instruments can only test for a few substances at most, such as formaldehyde or toluene," said Wang Zhaohui of the testing and research center of the Sports Engineering Key Lab of the General Administration of Sport in Wuhan. "Smelling is a more direct and reliable way to determine whether a sample is poisonous."