Is it safe to carry black soul gems?

In Skyrim, I came across the book Souls, Black and White. This book ends with the following passage:

Even if one were to ignore the guild strictures against the necromantic arts used to power black soul gems, it is dangerous to the caster to handle them for long. If the gem is not precisely the size of the encased soul, small bits of the caster's soul may leak into the gem when it is touched.

Is this true? Is there any danger to carrying around or using black soul gems? I have had three on me for a while and I don't think anything bad has happened to me as a result...

There is no actual danger in carrying black soul gems in the game. Although the dangers of black soul gems lore-wise has been evident for some time now, it's never been implemented into any of the games.