1) Many nations have been faced with the problem of...
2) Recently the problem has been brought into focus.
3) Recently the phenomenon has become a heated topic.
4) Recently the issue has aroused great concern among...
5) Nowadays there is a growing concern over...
6) Never in our history has the idea that...been so popular.
7) Faced with..., quite a few people argue that ...
8) According to a recent survey, ...
9) With the rapid development of..., ...