Cleaning Your Home: Good. Accidentally Poisoning Yourself: Bad.

Chlorine bleach, which can appear on ingredients lists as sodium hypochlorite, must not be mixed with any chemical other than water, as it can create dangerous and potentially deadly gasses. Likewise, when using bleach, remember to keep the area in which you’re cleaning well-ventilated:

 The complicated, century-long relationship between swimming pools and chlorine

Even new-fangled salt water systems can't quit chlorination.

Can drinking water be delivered without disinfectants like chlorine and still be safe?

Is chlorine needed to protect human health? As it turns out, there is very little data showing that a disinfectant residual in the distribution system has prevented waterborne outbreaks. A comparison of waterborne outbreak data from different countries shows that the Netherlands, the one country we evaluated that does not use disinfectant residual, has very little risk of waterborne disease. So in terms of microbial indicators of risks, systems with a residual disinfectant are not necessarily safer than those without.

Chlorine Accidents Take a Big Human Toll

Over the past 10 years, there have been hundreds of accidents involving chlorine nationwide, injuring thousands.

Chlorine Gas Toxicity

Gaseous chlorine is poisonous and classified as a pulmonary irritant. It has intermediate water solubility with the capability of causing acute damage to the upper and lower respiratory tract. Chlorine gas has many industrial uses, but it was also once used as a chemical weapon in World War I. Today, most incidents of chlorine exposure are through accidental industrial or household exposures. As for industrial exposures, there have been several instances of train accidents carrying liquid chlorine that caused the release of chlorine gas to the surrounding environment. At home, a mixture of chlorine bleach with other household products that contain acid or ammonia is a common source of exposure to chlorine gas.

Chlorine in the World: Good or Bad?

In recent times, chlorine and its compounds have come under public scrutiny. Greenpeace asserted, "There is no use of chlorine which we can regard as safe." (Malkin & Fumento, 1997.) Others have stated, "Dioxins are the most toxic chemicals made by mankind ..." (Chlorophiles, 1996, A). As with many useful raw materials from nature, chlorine is not without controversy.

Chlorine: the gas of war crimes

The 17th element of the periodic table has a dark history – it’s a relic of the first world war that reports say has made a reappearance in the conflict in Syria.

Chlorine: The Issue, The Reality and The Solution

I only wish the facts about chlorine chemistry would receive as much attention as the recent discovery about how to make fat mice thin. I sit in amazement at how excited Americans get about the possibility of a cure for obesity, but at the same time remain virtually ignorant about the innumerable, positive documented contributions that chlorine has made to our health and everyday lives.

Is Chlorine in Swimming Pools Safe?

The bottom line: We’re vastly better off having pool chemicals than not, and chemically treated pools are generally safe to swim in, especially if they are well maintained and ventilated. Add to that some time-honored advice that probably bears repeating: Don’t pee in the pool.

The Element Chlorine

Chlorine is a very dangerous material. Liquid chlorine burns the skin and gaseous chlorine irritates the mucus membranes. Concentrations of the gas as low as 3.5 parts per million can be detected by smell while concentrations of 1000 parts per million can be fatal after a few deep breaths.