When considering the idea of altering a persons skin colour in any way, it is first necessary to think about the psychological implications of this, which can be very damaging. To equate beauty with a certain skin colour is merely an illusion, and this is the thing that must be overcome rather than making any physical altercations to your appearance.
Secondly, whilst skin bleaching creams do exist on the market, they are highly toxic and can be extremely dangerous. These are known to cause fatal disorders such as skin cancer, so you are essentially putting your own life and wellbeing at stake if you do choose to endorse these creams.
There are several organic routes to naturally 'brighten' the skins tone. This includes using the juice from a tomato, mixed with lemon on your face which is known to have a very natural brightening effect, and does not cross over into the more dangerous bleaching territory. Almost oil is also said to be excellent for naturally lightening under eye dark circles.
i hope this helps.