Thank you all for your kind comments !
Robert - thank you for your very encouraging remarks ! I spotted her just as she used up the last of her bubble liquid and watched her expression change from a child's wonder (I was too late to capture her gaze at the bubbles) to sadness at the end of her day as her father drove them away). For some of the shots in this series I smiled at the parents and showed them the photos of their children - they were universally happy and proud at this foreigner taking shots of their precious ones.
Shoturtle - Shanghai is much better than Beijing in regards to dust (Beijing is located in a bowl-like depression and gets smothered by dust from the Gobi desert every Summer). The copious amounts of dust here are to do with the incredible amount of construction going on in the city for the last 15 years - at one time it was estimated 50% of all the world's high rise cranes in current operation were located here (trufax). Shanghai built more high-rises than the whole of Manhattan in the 10 years between 1995 & 2005 and still hasn't slowed the pace yet (my company is engaged in real estate so collating statistics is part of my work). Staggering. And very unhealthy.