Bronze is best known as an alloy of copper and tin, but copper alloyed with aluminum, arsenic, manganese, phosphorous, silicon, etc., can also referred to as bronzes.
Yes, it is, see this 2010 paper Eating artificially ripened fruits is harmful. Calcium carbide is extremely hazardous to the human body as it contains traces of arsenic and phosphorus. It is banned in many countries of the world, but it is freely used in India, Pakistan, Bangladesh, Nepal and other countries. Thus we are at risk of short-term and long-term health effects simply by eating fruits that are induced to ripen. Calcium carbide CaC2 is used to easily generate low levels of ethylene gas which can hasten the (outside at least) ripening of fruits like bananas, mangoes etc.
Stick it in Rice. Uncooked rice, of all things, traps ethylene gas like a pro. If you stick a mango in some rice, it will ripen quicker than if you leave it on the counter. All you have to do is submerge it deep down in the rice to make sure itâs covered on all sides. You can do the same with avocados.