What are the masks people wear in photos of HoChiMinh City?

Ive been looking at pictures of HoChiMinh City and in some people are wearing face masks as they ride a bike - why the masks? Thanks!What are the masks people wear in photos of HoChiMinh City?
i will have to agree with the others ; the mask are worn to protect against airpolution.. however they only work to ward off ';particular[dust] polution';.. gasses and other fumes can build up on such a mask and make the problem worse...but basically i guess it is what they can afford and or have available....What are the masks people wear in photos of HoChiMinh City?
Pollution is very big issue in VN now. People wear to protect inhaling the smoke coming out from the vehicles on street.
They are trying to ward off dust and pollution. The Ladies use them mask to protect their face from sunburn.
The same reason we would wear them.





Under communism, there is very little respect for the environment. (Here in the USA the socialists are massively in favor of the environment. Go figure.)





Because of lower grade gasoline, as one example, some particles are large enough to see. Even communists over there would not want to inhale them. I simply wish those particles could be inhaled by American Democrats.
Oh yes, they wear masks because it is polluted in HCMC. Some women also wear other stuff to protect their skin from the ultraviolet.

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