A hair straightener is not safe or effective in treating lice infestations. While it's true that nits, or lice eggs, are unable to endure extreme heat, it's important to note that using a hair straightener alone is not an effective method for eliminating them. While heat can help in killing nits, it is recommended to use other treatments. Exposing nits to temperatures above 130°F for over 5 minutes can kill them. However, reaching and maintaining such temperatures on the scalp using a blow dryer alone can be challenging and not recommended as it also poses a risk of scalp burns. It's important to use proven treatments specifically designed for lice removal. If you or someone you know is dealing with a lice infestation, consult a professional who can provide appropriate guidance and recommend the best course of action.