Other substances don't combine quite so favorably. Bleach and ammonia are an excellent example. Another example is bleach and vinegar. I know, I know... if you run a search on Google you'll read that vinegar increases the killing power of bleach. Yes, it makes the chemicals more likely to kill you or your kids or your pets. It also helps to kill anthrax spores. If you find yourself in a position to do an emergency decontamination of an item coated with anthrax, by all means, mix the bleach and vinegar. If you just want a sparkling clean bathroom, use a product designed for that purpose. Bleach combines with acids (e.g., vinegar, lemon juice) or certain bases (e.g., ammonia, drain cleaner, urine in the catbox) to release chlorine and chloramine vapors. Realistically, you're probably not going to kill yourself mixing a little bleach and vinegar in a bucket of water (as opposed to mixing them directly). You can get a lethal dose of chlorine by taking a few breaths of it at a concentration of 1 part per thousand in air. You can't gauge the concentration by smell, since most people can smell chlorine at a reasonably safe concentration of 35 parts per million. However, you can get a nasty chemical burn, especially of your eyes and lungs. Mixing these chemicals just seems like an unreasonable risk to take.
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