Over the weekend, in Australia, “an overzealous cleaner armed with chlorine” added chlorine to a tidal pool in Coogee's historic Wylie's Baths. See the Sydney Morning Herald.
The chlorine was added to eliminate some of the algae because algae can make rocks slippery. But, unfortunately, the incident served to remind us how hard chlorine can be on living things.
The chlorine killed a beloved octopus that lived in the baths. According to the Wylie trust, which maintains the baths, “the death of its resident octopus was ''apparently as a result of chlorine contamination''.
''I've been swimming there for 11 years and I've never seen anything remotely like this,'' said Coogee resident Matthew Martin, ''not only was every marine fibre bleached white and dead, so was every marine creature that usually lives in the pool.''
Chlorine certainly has a place in maintaining healthy water. As the article points out, one “success” of the cleaning process is “to routinely remove slip hazards posed by algae growing around the pool.” But, the trust seemed open to the idea that they may have overdone the chlorine this time: ''it appears in this instance, we got it wrong.”
This goes to show that chlorine also has a dark side. It is a powerful chemical. While useful in some contexts (like carefully sanitizing water) it can be terrible for you in others. Here, I think I would err on the side of caution by limiting chlorine exposure. For example, after swimming, I would recommend washing the chlorine off of your hair and skin. Why sit around covered in chlorine all the time? Clearly, it’s not good for your neighborhood octopus. What’s it doing to your hair and skin?