Ninety crumbling tiles are quite a lot, considering that this level isn't that long. To complete this achievement, you need to be using a slow moving character for you to succeed in turning around the tunnel so that you won't speed out of it even you are still halfway through. The Lizard is perfect for this achievement. You will need to try and crumble as many crumbling tiles as possible because there is surely no time to count tiles. Running on the bigger platforms is recommended as you can dislodge more tiles at a time.
The Duplicator is also a good character for the achievement since his duplicates can crumble tiles, making the tedious work of knocking off tiles much easier. Go all the way around the tunnel and let all your duplicates do all the work for you. This way you can crumble even more tiles than the Lizard. And in addition to that, this can be even more efficient if the Duplicator is at its maximum number of duplicates (which is 6). However, it is not recommended that you buy the Duplicator for 6000 power cells just for this achievement's sake. Unless you want to buy this character for other reasons, it is recommended that you just beat Level 40 and unlock the Lizard for this achievement. It just isn't worth it.
Beware that if your computer is laggy, you will probably have a hard time passing this, since lots of crumbling tiles crumbling at the same time lags the computer easily.