Two main hydroxides are responsible for this category of toxin. Potassium and sodium hydroxides are added to multiple household cleaners because of their abrasive ability to clean everything from floors to rusty pipes. Their caustic nature makes them unbeatable at purifying, scrubbing, and soaking grime away. We are very familiar with two substances derived from these chemicals: bleach and lye. Chlorine bleach is created when adding chlorine to sodium hydroxide. The result? It can strip the color right out of paint. Lye has been used forever as a cleaning agent. Both sodium hydroxide and potassium hydroxide can be used to make lye.
While the jury is still out on long-term effects of use, what we do know isn't pleasant. Breathing the vapors in even temporarily can do great harm. Headaches and respiratory distress can happen within moments of use. Even if no symptoms are present, the lungs and esophagus are being treated to a very caustic coating of these two chemicals. With skin contact, tingling or burning sensations, dermatitis, or skin lesions/rashes are very common. Left on the skin too long, actual burns will develop.
Interestingly, one of the uses of these chemicals is in the disposal of roadkill and other animal remains. When left to sit in a heated solution of hydroxides for several hours, all that is left is the bleached hollowed bones of the creature or yes, human (history shows us this has been done frequently). The bones are so fragile at that point, they are easily turned to dust with little pressure.
So, I guess what we are left to wonder, then, is this: why on earth would we use something so strong and lethal in a common household cleaner?