Can people please forget about water in the fuel, waxing etc.? It's unlikely to be valid, otherwise jets would be dropping out of the sky daily all over the world.
For a start, Beijing is holding the Olympics shortly and they have thoroughly renovated everything aviational. As for waxing, the cloud point (at which wax freezes out of the fuel) for Jet fuel is very low and its tested when the batch is approved.
As for water, (as a former terminal engineer before joining an airline), I can tell you that oil companies are paranoid about water in jet fuel storage tanks. Furthermore, the fuel will have traveled through at least THREE filter/coalescer units (terminal, receiving station and final loader) which remove dirt and water before it is loaded into the aircraft tanks that should leave it clear and bright. So absent massive water contamination, that would by now have affected dozens of aircraft, in all probability this is a non-issue.