Sure can, absolutely no problems what-so-ever and it is absolutely safe for both veg and flowering stages.
It will not cause anything, except faster growth and will definitely NOT increase any risk of hermaphroditism.
18/6 is optimum. Any more than 18 hours is stressful and can cause problems.
24/0 is totally wrong, un-natural, absolutely wrong, un-healthy, completely wrong and WILL cause all sorts of issues.
Nothing on Planet Earth can survive and/or function properly without an awake/sleep/awake/sleep cycle.
People who try 24/0, usually only ever try it once!!
A cannabis plant needs to sleep and undertake certain metabolic processes during the night cycle to function and grow properly. Without a night cycle you will get a dysfunctional and completely exhausted and frazzled plant.
Could you imagine going weeks/months without sleep?
Besides, cannabis can only grow so much during any 24 hour period and this growth tops out at about 18 hours, meaning running your lights longer than 18 hours is basically a waste of electricity.
Remember - 18/6 is optimum for all cannabis, autos and photoperiod plants in vegetative growth.
Think of the 6 hours of "sleep" as 2 hours to recover from the day, 2 hours to rest and 2 hours to get ready for the day ahead.
This is basically what occurs during the "sleep" cycle and is vital for prime plant health.
A stressed and exhausted plant can not grow prime flowers. Pure and simple!
Hope this helps,.........
Organoman. (and defender of cannabis from un-natural practices!)