I was wondering if there are any possibilities of tearing something while doing dealdifts...
Always when i deadlift my arm with the underhand grip (my "weak" arm - left) seems to have a lot of stress from the movement....and im always cautious when going heavy....
Should i be concerned?
yes there is always a possibility, but if your a natural i find it very high unlikely tho. Personally i never do the under/over grip....2 reasons: i feel it twists my back a bit+underhand grip puts alot stress right on the biceps. instead when i go really heavy and my grip cant handle the weight i use straps and a overhand grip.
they key (for protecting biceps) when you start the movement is that you arms should be straight....if they arent and you pull a heavy weight from the floor (specially with the mixed grip) bad things could happen to your biceps.
obviously there are other dangers when deadlifting: lower back, hamstrings etc..as cap86 mentioned.
personally i think if your a bodybuilder you should mostly focus on rack deadlifts (starting the movement just below your knees or so)
75% of the time and do regular deadlifts wth medium weights of the floor with a wide grip the remaining 25%.