Is there a quick way to find all columns in SQL Server 2008 R2 that are encrypted/have encrypted data?

Question

Is there a quick way to find all columns in SQL Server 2008 R2 that are encrypted/have encrypted data?

I need to nullify the data in all encrypted columns in a development server (according to our business rules). I know most of the columns because we use them regularly, but I want to be thorough and also I want to be able to prove that I've found them all.

I've searched the web, looked in INFORMATION_SCHEMA and checked the DMVs I thought would be useful and also sys.columns and sys.objects -- but so far no luck.