Updated

Whitney Foard Small loved China and her job as a regional director of communications for a top automaker. But the air pollution led to hospital stays and finally a written warning from her doctor telling her she needed to leave.

So the Ford Motor Co. executive became another expatriate to quit China because of its notoriously bad air. Other top executives whose careers would be boosted by a stint in the world's second-largest economy are put off.

There is no official data on the numbers leaving because of pollution, but executive recruitment consultants say they are noticing that it is becoming harder to attract top talent to China. The European Chamber of Commerce in China says pollution is almost always cited as one of the factors for foreign managers leaving.