Swimming in chlorinated pools can lead to cancer: study

September 13, 2010

Swimming in chlorinated pools can cause an increased risk of cancer in bathers, Spanish researchers said on Monday.

Researchers from the Barcelona-based Centre of Research in Environmental Epidemiology (CREAL) and Research Institute Hospital del Mar studied changes in indicators of mutagenicity -- permanent mutation of the DNA -- among a group of swimmers in an indoor chlorinated pool.

"The evidence of genotoxic effects were observed in 49 healthy adults after for 40 minutes in a chlorinated indoor pool," CREAL said in a statement on Monday.

Researchers found indicators of an increase in in healthy subjects as well as potential respiratory effects from the cholorine used as a disinfectant, the statement said.

The study was published on Sunday in the US journal .

The co-director of CREAL, Manolis Kogevinas, said the findings should not put people off swimming.

"The positive health impacts of swimming can be increased by reducing the levels of these chemicals," he said.

"In no case do we want to stop swimming, but to encourage the reduction of chemicals in swimming pools," said Kogevinas, who suggested the problems caused by a reduction in levels of disinfectant could be offset if swimmers showered before taking a dip, wore bathing caps and refrained from urinating.

More information: Genotoxic Effects in Swimmers Exposed to Disinfection By-products in Indoor Swimming Pools, Manolis Kogevinas, et al., Environ Health Perspect. doi:10.1289/ehp.1001959

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5 / 5 (6) Sep 13, 2010
Trihalomethanes (THM), a byproduct of chlorine disinfection, are widely suspected of causing cancer. Many water utilities are busy reducing the amount of chlorine used for drinking water, reducing detention time (the time it takes to get from the filtration plant to your tap), and using alternative disinfection methods, such as UV, ozonation, and the like.

Whether this could be scaled economically to a swimming pool is an interesting question...
2.7 / 5 (7) Sep 13, 2010
The other thing is that it isn't the chlorine that does the work in the pools. Real, honest to betsy 'pool shock' is actually pure calcium Hypochlorite. When added to water it releases chlorine, but it is the the hypochloric acid that kills the bacteria .

This is the exact same acid that the human immune system uses to kill all internal pathogens. It is a 'cell wall' bursting trick, so the pathogen cannot develop an immunity to the hypochloric acid. This is why the body uses it. Duh!

Now, in modern pool shock, there is a very complex mix of chemicals, and not so much of the calcium hypochlorite.

It is only honestly suggested that this other toxic mix is the culprit, not the natural immune system chemical that the body actually uses.

Jim Humble has promoted the use of Calcium Hypochlorite to cure pathogens and stop disease in the human body, and quite successfully. Thus the emergent big pharma attack on anything that threatens their empire - This is their new war on MMS and MMS2.
2.7 / 5 (9) Sep 13, 2010
FOLLOW THE MONEY TRAIL. Who fiances these groups, who is involved in them who heads them,what is their background,where do they come from, who hired them who promoted them,and who funded the studies?

I suggest you look closely at the messenger in this case, if you take what I told you above, as being something other than ranting. You will very likely find big pharma connections behind this 'study'.

What is being done, is a 'casus belli' and background is being created to make sure that pool shock is somehow pulled, as Sodium Cholrite (MMS) was also forced off the market with absolutely zero in the way of deaths or real actual complaints. yet at the same time, drugs promoted by big pharma have killed hundreds of thousands in the same time period.

Recall or know for the first time that the US's FDA is actually chock full of big pharma ex-employees, and FDA employees end up with high paying jobs in big pharma. In reality there is no control over the FDA that is in the public interest.
5 / 5 (1) Sep 13, 2010
I don't doubt you are correct, always bear in mind that tobacco is big pharma too!
5 / 5 (2) Sep 14, 2010
KBK, before making random accusations, why not just go read the article? It took me less than a minute to find and is free:

The funding was provided by Spain's Plan Nacional and the article was published in an NIH journal. There are certainly many reasons to criticize the pharmaceutical industry, but this is not one of them.

Before posting drivel, why don't you take a few seconds to check on what you are saying? It is important to keep a watchful eye on corporations, but careless statements by people like you only serve to muddy the water and make it harder for anybody to get any real work done.

BTW, physorg, you should have a link to every journal article you reference, whether it be the full article or just the abstract. If want to make a science site, then it is time to act like scientists.
3.5 / 5 (2) Sep 14, 2010
Commenting on ab3a,
There are already on the market water treatment solutions that allow a reduction of 60% to 90% of chlorine in swimming pools (they do not offer a total substitution, as some chlorine is still required to keep the water "clean". You can find these products (e.g. ozonizers and UV) for sale even in ebay. Or just google "pool water treatment" and find them. The reduction in chemicals consumption makes these systems economically feasible.
By the way, I have an idea for a cheap system to help maintain water in pools dissinfected:
-adaptable to new and existing pools
-zero additional chemicals
-no maintainance
-zero running costs
... if anyone is commercially interested, please contact me.

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