Re-read the part about accidents. Accidents aren’t Darwin awards. Accidents happen in Level 4 Bio facilities by some of the most highly trained individuals in the world. I’m guessing the accident rate for kids would be much higher than 1 in a million.

And you can still buy an adult chemistry set for your kid and supervise them to the extent you feel is appropriate.

Maybe you personally have never had an accident but to err is human and kid’s products do need to be designed for the masses and accounting for the fact that their bodies, moral compass and decision making is still in flux.