Chlorine in Water
Chlorine has been added to water in the US for decades. It was added to combat serious outbreaks of diseases such as typhoid and cholera which were prevalent in the 1800's. While it is effective, it is also dangerous at the same time. Levels of chlorine in our drinking water reach stages where they have been the cause of heart disease because it aids in the blocking of arteries.
A good way to get chlorine out of your water before it is consumed is to purchase a water filter.
You also put chlorine on your body through your shower and shower filters are available to reduce this toxin.