Hey,
I haven’t heard about pollution having these kind of effects – can you link to where you read this? I think if you attend to your hygiene like you would anywhere else, you’ll be fine in Chengdu.
I don’t think you really need to do anything, but you can optionally:
– Reduce outdoor physical activities on days when the pollution is particularly bad (you can check the pollution pretty easily here online)
– Get a pollution mask (like a Respro or Totobo) if you run or cycle
– Get an air purifier or air ionizer for your home