I have a six-year-old daughter and a 13-month-old son.
My daughter knows exactly what e-liquid is, why she shouldn't touch it, and what to expect from Daddy if she does. See, I'm a parent and I parent. I taught her at an early age that packaging does not always speak to the contents. When in doubt, she asks. For instance, when she sees air freshener spray in a can with pretty colors and a nice smell, she knows that it's not for her to spray in her mouth, her eyes, or anywhere near her face. When she wants to use it, I taught her how to understand the nozzle and how to point and aim away from herself. She obeys. She can get one "spray." And only after asking Daddy.
My 13-month-old, on the other hand, finds the oven and dishwasher the most appealing. The handles are at the perfect height for him to stand and grab while trying to pull himself up. Interestingly, neither of them have "child-safety locks." One day, he managed to pull the dishwasher door open---while it was on. I got to him fast enough that he wasn't harmed. Although, the scalding water was shooting and splashing around wildly. Close call!
At some point, people will have to realize that we live in a world full of things that are appealing to children. Luckily, children don't have to navigate the terrain by themselves. As long as parents actually parent, a child might even be able to walk to school without picking and eating poisonous berries off of bushes. Even though they have pretty colors and look similar to something they would eat, children can actually be taught the difference.