Chlorine is a deadly poison in its pure form, yet we eat it all the time! How can that be?
Chlorine is an element, just like iron or oxygen, but it never occurs in nature by itself. It’s most commonly found mixed with the element sodium in a compound called sodium chloride, which is the chemical name for ordinary table salt! So when we eat chlorine, we eat it mixed with sodium, and in that form chlorine is harmless.
Pure chlorine is used as a poison to kill germs in our drinking water or in swimming pool water. Chlorine is so poisonous to bacteria that water can be purified by just one part of chlorine for every 200,000 parts of water!
Most of the chlorine used today is separated from the sodium in salt by means of an electrical current. Chlorine is used not only as a disinfectant, but as a bleach for fabrics and paper.