There is a running thread here of known and reported flavors that can crack or melt polycarbonate-type plastic (clear). Currently there are two flavors listed from Virgin Vapors. Should the flavor you used not be on the list, it would be appreciated to add your flavor and the vendor to the thread to make it more complete for other vapors such as yourself.
http://www.e-cigarette-forum.com/forum/tanks/219179-lets-make-list-juices-flavors-crack-tanks-ce2s-clearos-29.html#post7203876
There are no reports that vaping these so-called volatile juices are unharmful in any way, other than the fact that inhaling the material leached from the plastic obviously would not be a good idea. Used in a safer container, such as glass or a safer plastic such as polypropylene (frosted), these flavors are perfectly safe.
_________________________________________________
To anyone not familiar with polypropylene or glass tanks, here are inexpensive recommendations for one of each:
Pyrex glass tanks
IBTanked - Get Tanked With Us! This vendor makes high quality, durable, yet inexpensive glass tanks starting at less than $18.
You will get a pyex tube of the length and diameter that you choose. Choose from a wide selection of stainless steel or acrylic endcaps. A selection of drips tips and cartomizers are offered for sale separately.
Polypropylene plastic tanks
510 Pro DCTank Combo This is a complete tank kit including a polypropylene tube, metal endcaps, drip tip, and a 5-pack of cartomizers.
Polypropylene is a plastic material safe for use with the volatile flavors. It is the same material used in medical syringes. It has a frosted appearance, unlike the crystal clear plastic of polycarbonate.