# CFCs BAD, pool chlorine... eh?

**URL:** <https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442>\
**Category:** Great Debates\
**Created:** [August 27, 2006, 7:18pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442 "2006-08-27T19:18:22Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Placid\_Liver](https://avatars.discourse-cdn.com/v4/letter/p/e99b99/32.png) [@Placid\_Liver](https://boards.straightdope.com/u/Placid_Liver)\
**Post date:** [August 27, 2006, 7:18pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442/1 "2006-08-27T19:18:22Z")

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There was a lot of fuss about refrigerant and aerosol propelant gases killing the ozone layer, surely chlorine used to keep swimming pools clean also gets into the atmosphere and causes problems too? Why has there not been any movement to reduce pool chlorine usage?

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**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\
**Post date:** [August 27, 2006, 8:01pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442/2 "2006-08-27T20:01:55Z")

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> [@Placid Liver](#):
>
> There was a lot of fuss about refrigerant and aerosol propelant gases killing the ozone layer, surely chlorine used to keep swimming pools clean also gets into the atmosphere and causes problems too? Why has there not been any movement to reduce pool chlorine usage?

IIRC chlorine down near the surface doesn’t survive long enough as an independent substance to reach the ozone layer; CFCs do survive to that height, and break down **there** , neatly depositing the chlorine where it can do it’s damage. BTW, this seems more like a General Question than a Great Debate.

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**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\
**Post date:** [August 27, 2006, 8:15pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442/3 "2006-08-27T20:15:31Z")

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IIRC it’s the F not the Cl which is the item which is accused of creating havoc with the ozone layer.

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**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\
**Post date:** [August 27, 2006, 8:37pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442/4 "2006-08-27T20:37:34Z")

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> [@kanicbird](#):
>
> IIRC it’s the F not the Cl which is the item which is accused of creating havoc with the ozone layer.

[Wikipedia](http://en.wikipedia.org/wiki/Ozone_layer) claims it’s chlorine, not fluorine :

> [@](#):
>
> The ozone layer can be depleted by free radical catalysts, including nitric oxide (NO), hydroxyl (OH), and atomic chlorine (Cl) and bromine (Br). While there are natural sources for all of these species, the concentrations of chlorine and bromine have increased markedly in recent years due to the release of large quantities of manmade organohalogen compounds, especially chlorofluorocarbons (CFCs) and bromofluorocarbons. These highly stable compounds are capable of surviving the rise to the stratosphere, where Cl and Br radicals are liberated by the action of ultraviolet light. Each radical is then free to initiate and catalyze a chain reaction capable of breaking down over 10000 ozone molecules.

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**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\
**Post date:** [August 27, 2006, 9:34pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442/5 "2006-08-27T21:34:46Z")

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> [@](#):
>
> The ozone layer can be depleted by free radical catalysts

Chlorine in pools normally gets converted to ionic forms (NaCl, HCl, etc), or chloramines, [which break down into ions](http://www.environmental-expert.com/articles/article324/article324.htm). Ions don’t catalyze ozone breakdown. In fact ion formation is a [major mechanism for removal of ozone depletors from the troposphere](http://www.nas.nasa.gov/About/Education/Ozone/chemistry.html).

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**Author:** ![Placid\_Liver](https://avatars.discourse-cdn.com/v4/letter/p/e99b99/32.png) [@Placid\_Liver](https://boards.straightdope.com/u/Placid_Liver)\
**Post date:** [August 28, 2006, 3:27pm UTC](https://boards.straightdope.com/t/cfcs-bad-pool-chlorine-eh/370442/6 "2006-08-28T15:27:28Z")

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> [@Der Trihs](#):
>
> IIRC chlorine down near the surface doesn’t survive long enough as an independent substance to reach the ozone layer; CFCs do survive to that height, and break down **there** , neatly depositing the chlorine where it can do it’s damage. BTW, this seems more like a General Question than a Great Debate.

Indeed it was meant to be in the questions forum, I thought I’d posted another message straight after the original asking a moderator to move it, but I guess it didn’t make it through ☹
