For a start, there's dust all over them. If you paid for shop scans I'd be asking for some money back. Or if you scanned them yourself then it might be time to invest in some pecpads.
#1 - is the black line diagonally across the whole thing what you're talking about, or a powerline? Nothing else wrong there but what looks like dust, same with #3 #4, and #6. Could also be emulsion scratches, look at them closely in good light to see.
#2 looks like a long eposure of a point light source, and moved around a lot. There are also darkish lines horizontally across, is that the problem? I see a similar thing on #5. I've had that happen on my v750 with the betterscanning wetmount holder, if the holder is not aligned properly the light gets confused and you can scan weird dark/bright lines into it. Or they could also be dev issues, not agitated properly and/or insufficient developer.