I am thinking this is also known as ficus elastica and if so then it is on the safe plant list under rubber tree. BUT I am not 100% sure they are one in the same. It talks about a white sap that is very sticky to the tongue so that makes me question it but again it may be the same plant listed as rubber tree. They look VERY similiar and when looking up robusta a couple of links to the ficus elastica came up