The latest panic seems to be water. People are buying bottled water en mass. I had to chuckle a bit, one local bottler's 'glacier fed' source was reavealed to come from the tap. In the unlikely scenario of a pathogen deliberately introduced, will mechanical water filters,boiling, chemical treatment be adequate?<br><br>

Chris, <br>I agree about the puzzle of buying bottled water. Without any refereces to guide me, I would think that the guardian filter system with the viral protection module or boiling would eliminate any bacterial or viral threat. Keep in mind that water really needs to be at a rolling boil, not just hot to kill microorganisms.<br>Chemical agents are just chemical contaminants that may be removed by charcoal filtration (SWAG).<br>I will look into this and see if I can answere the question more fully.<br><br>Jeffery S. Anderson, M.D.<br><br>

Why not use distilled water. It's priced similarly to bottled ( "spring" ) water in the supermarket. Despite its flat taste, it should be "pure". It's easily aereated to address the flat taste, and, by the way, it makes truly outstanding coffee.<br><br><br>

>>>Chemical agents are just chemical contaminants that may be removed by charcoal filtration (SWAG).<<<<br><br>I don't have an answer to the specific issue on charcoal filtration, but I do know a few things to consider if you are relying upon it based upon info I've learned from keeping tropical fish.<br><br>Charcoal depends upon a poreous surface area to make contact with contaminents in order to bind them. Once "satuarted" the charcoal becomes ineffective. Worse yet, it may actually start to dump contaminents back into solution. So it's important to make sure your charcoal is clean.<br><br>One person I know has two in-line filters with a tap in between. He periodically tests the water from this tap for chlorine. Once it appears, he knows that the first filter is no longer effective so he replaces it with the filter from the second unit and put a new cartridge in the second unit. The second unit filters out contaminants from the first that get by the first before he has a chance to check the water. <br><br>He always puts in a fresh cartridge in the second unit (rather than only replacing the first unit's cartridge) so he never has to worry about testing the water after the second unit.<br><br>I also recall hearing about a technique to regenerate activiated carbon. I will try to see if I kept notes on that technique. Obviously, it's much better to use new cartridges but that my not always be possible in a an emergency situation.<br><br>Again, I must caution that this information is what I have learned from folks keeping tropical fish and I do not know if the same logic will apply towards maintaining safe drinking water.<br><br><br>Willie Vannerson<br>McHenry, IL

More info:<br><br>I found a reference in my notes that modern charcoal (activated carbon) cannot be renewed. Bone charcoal, which was once used in the aquarium hobby, could be renewed, but I don't have notes on how to do that.<br><br>Also, I noticed that the flow rate could affect efficiency. The slower the flow rates the better to allow the carbon to bind to the chemicals. The person who installed the two-filter system I referenced, also stated that the filters were not particularly effective in removing chlorine and chloromine. So this may be evidence that carbon may not filter out all foreign chemicals. Hence, I would not rely upon it solely as a source for safe water under emergency situations.<br><br><br>Willie Vannerson<br>McHenry, IL

Here is a link for you. The SAS, British Civil Defence and us use these for water purification. They have NATO stock numbers and probably available in US. The SWP, MWP and PWP are field tested may go into different sizes of kits if you just do not mind the taste of iodine. I also use it for diarrea treatment:))<br><br>http://www.pre-mac.com/MIL_P1.HTM<br><br>PWP achieves a zero virus count in the design time of 2 minutes - a reduction of 99.99%.<br><br><br><br><br><br>Survive and Protect

Really doesn't look much different than the Guardian Sweetwater filters. Obviously, the larger units are different and resemble reverse osmosis systems.<br>I think that to decontaminate "city water" all that would be required is a suitable particulate filter, cartridge to remove chemical impurities (after all, nerve agent is a simple chemical contaminant), and an ultraviolet unit that will kill any viruses or bacteria in your water.<br>Just a thought<br><br>Jeffery S. Anderson, M.D.<br><br>

The local water authorities were interviewed on the local news last night. They found deliberate water contamination a needless worry. The sheer volume of water, time in the environment and standard treatment would make short work of any biological assaut. They did state a natural disaster could compromise quality in the actual pipes, so a household filter is still good insurance. If a physical disruption of supply is a concern, then stored water ( rotated frequently and/or treated) is an option. After the Northridge quake, only a few water systems were actually compromised. We had plenty just north in Ventura County. The deliveries of bottled water kept up with basic demand. It was rationed for consumption and basic hygiene. Unless transportation is actually disrupted ( ie flooding) , business will respond, be it water or gas masks.( I know what a lot of children will be wearing come Halloween this year.)<br><br>

>>>business will respond, be it water or gas masks.( I know what a lot of children will be wearing come Halloween this year.)<<<<br><br>Actually, I overheard someone on the train this week mention that sales of fireman and policeman costumes have taken off. That's a positive sign of children choosing role models.<br><br><br><br>Willie Vannerson<br>McHenry, IL