by Jotapay » Thu 31 Dec 2009, 12:33:18
$this->bbcode_second_pass_quote('culicomorpha', 'I')'ve looked at many of the filtering technologies, and they all leave something to be desired in my opinion. The craziest thing the municipalities do is to fluoridate the water. It's impossible to remove except with R.O. or distillation, both of which are wasteful processes. The water sources for many places are actually fairly good, as most municipalities at least try to protect their reservoirs and watersheds, but then they poison it with fluoride at a dose that is not that far below the toxic dose. Ground water can be better, or it can be very heavily contaminated. That's a crap shoot, but it seems like the number of known-polluted aquifers increases every year.
Regardless of the filtration type, it doesn't really help much since these technologies typically cannot filter fast enough for a shower without spending a lot of money on a whole-house-sized system. I came across a study a few years back - I'll see if I can find it again - that determined experimentally that the vast majority of exposure to volatile organic chemicals (VOCs) happened in the shower, and that only a small amount is absorbed via drinking water. So if you can't filter your shower, and your shower accounts for, say, 90% of your total daily exposure, then it doesn't matter if you filter your drinking water or not.
Sorta takes the wind out of your sails. I have more thinking to do. I guess I need to do some reading about plumbing and see if the expense/time is even worth it.
I'd really like to see the study about VOCs in the shower. I studied VOCs a little in one environmental engineering class. They are nasty little buggers. They are carcinogens and can give pregnant mothers a three-headed baby. Just kidding, sort of, but I try and keep them far, far away from me. I'd never read about exposure in a shower before. I wonder what the typical exposure level and resultant cancer rate is in typical showers in different cities.
Remembering my book lernin', VOCs would usually be actively absorbed by the skin and concentrated there. They would then be transported by the blood around the body until they broke down, depending on their half-life. Depending on the type of VOC, birth defects are a real issue.