Yong Xiaoyan, puts on a nose mask at her office in Beijing December 11, 2014. The office worker said she has used the mask everyday since she found out she was pregnant and was concerned that Beijing's air pollution could harm her foetus. The nose mask which was developed by a medical company can filter out tiny particles of pollution, the company said. Awareness of the dangers of Beijing's skies is on the rise, thanks to growing data on its air quality. China will "declare war on pollution," Premier Li Keqiang told parliament in an opening address in 2014. A tougher environmental law took effect on January 1, while a new environment minister took charge on Friday. REUTERS/Kim Kyung-Hoon (CHINA - Tags: POLITICS SOCIETY ENVIRONMENT BUSINESS)

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