The China Smog Baby meme / troll was invented by Oblivion_Butt_Banger on Twitch.TV.
The troll is designed to lure unsuspecting twitch streamers into reading a NSFW message on stream. The format is as follows.
“Hi from china! Love stream – question, china smog kill all china babies. How much for you to sperm in cup and mail to china wife so we have white baby with strong lung? Please thank you”