Hi there Charlotte! Well, about the first one, it should be something like this: "En años recientes, se ha vuelto (se ha considerado) mucho más aceptable...". It's not literal at all, but I think it's accurate enough. And about the second one: "Un factor que contribuye mucho (en gran medida) al problema es..." . Again, nothing literal at all. "En gran medida" sounds better than "mucho" there, since it's something really difficult to measure, you know. You could also use the verb "agravar" (to make things worse, to aggravate), since it's something contributing to a problem. If you did, it should be like this: "Un factor que agrava el problema...". Hope this helps :). Anyway, you should take any other answer. Anything should be better than this.

En los últimos años se ha convertido (ha llegado a ser) mucho más acptable... Un factor que contribuye mucho (en gran medida/de manera importante) al problema es... I recommend you a good tool to get accurate translations for expressions English/Spanish and Spanish/English. This is it: http://www.linguee.com/ It's not an automatic translation, like google, it's very accurate because it's taken from webs in different languages, made by professional translators. It's totally free. Ciao Charlotte

En años recientes, ha llegado a ser mucho más aceptable... Un factor que contribuye mucho al problema es... Saludos.-