[ Based on what he's learned from Hawke, he can very comfortably slot it into the "disturbing" category, but he's not gonna let that cat out of the bag. ]

All we know is that it's probably dangerous, could be man made or could be environmental, and nobody seems to know for sure.

[ He throws his hands up, not that Zevran can even see that. ]

So basically we don't know anything.