Here's why:

* Dangerous Reaction: Mixing iodine and hydrogen peroxide creates a very reactive mixture that can produce toxic and corrosive fumes. This reaction can release iodine gas, which is highly irritating to the lungs and can cause respiratory problems.

* Potential for Fire: In some cases, the reaction can be so vigorous that it can cause a fire or explosion.

If you are working with iodine or hydrogen peroxide, always follow these safety precautions:

* Store them separately: Never store iodine and hydrogen peroxide together.

* Wear appropriate safety gear: Wear gloves, a lab coat, and eye protection when handling either substance.

* Work in a well-ventilated area: Make sure there is good ventilation when working with iodine or hydrogen peroxide.

* Never mix them: Do not mix iodine with hydrogen peroxide under any circumstances.

If you have any questions about the safe handling of these chemicals, consult a qualified chemist or safety professional.