By my calculations, in about 20 or 30 years the market for hearing market for hearing aids in China is going to be booming, for the following reasons:
A) The horns. Honking in China is not like the US. You honk to greet. You honk to let someone know you're behind them. You honk when you pass. And you damn sure honk when you think someone has intruded into your space in the slightest. Thing is, they have the same loud horns that are used in America for emergency warning. Someone should make a "Asia" horn that is softer and lower.
B) Conversation level. For some reason, people just talk louder here - it's just a cultural thing. It's not quite shouting, but most people talk with a very full, quite loud voice. Although for some reason, some Chinese women speak so softly you can barely hear them. Must have something to do with notions of feminine modesty
C) Cell phones. The decibel level doesn't drop one iota when people switch from face-to-face communication to cellular. If anything, it sometimes increases. People don't seem to have grapsed that constantly having someone shout into your ear can be a bad thing, especially when you have your nifty little in-ear bluetooth headset.
D) Music. Young people the world over seem to like loud music, but in many places this is expressed mostly in clubs and rock concerts. Now I haven't been to any rock concerts here, but the clubs certainly throb as violently as any in Europe or the states. What is different is that you will hear ear-splitting music blasting form a store fronts in the cities, as if this would have an enticing effect on passers by. I have seriously covered my ears while walking down the street. The increasing ubiquity of MP3 players and iPods can't help this any.
Most people in the world don't seem to be taking threats to their hearing seriously - in Chicago I constantly saw people iPodding it on the L, even though you have to crank up the volume to hear over the train, and this has been shown to kill your hearing. But safety is especially unconcerning to the Chinese at this point; this is a country where most people still don't where seat belts, and tell you reassuringly that it's ok when you try to put yours on. There are going to be a lot of people with hearing problems in the coming years - I just hope the hearing aid manufacturers are getting ready.
Wait, scratch that. They're probably already made in China.