It's only as dangerous as the person using it! If common sense is used, there is no danger. I keep mine locked up in a safe with other items like hand guns. That's how dangerous it can be. All precaution must be taken around kids and pets. My labs are curious and wouldn't hesitate in tasting it had they the chance! My 4 year old granddaughter might play with it if left out. I've had a supply for a few years, not the same bottle. When a bottle is finished, I even wash it out with hot water and soap before tossing the bottle. I also put the washed bottle in a plastic bag then toss it. Like with my pistols and rifles, I'm into hunting and target competition, I treat pure nic in the same manor. You can't be to careful. When handling and mixing, I do it right by a sink. I wash everything thoroughly, icluding my hands with soap and hot water. Never had any problems. Over protective, you bet!
Dave