I too would worry about some sort of reaction due to the uv and/or heat between the plastic and the water. While uv works well to disinfect, it should not be trusted to do so with surface water. Some infectious items are capable of surviving all but a highly focused uv source. Also, remember that uv disinfection is only valid at the source, when you are using the water or keeping it in the plastic vessel. It does not guard against later infection as would usage of some sort of chlorination disinfection (ie. bleach, pool shock, etc) due to the residual chlorine level produced. This is what deters bacterial growth in water mains. Unfortunately, even then, it still occurs. I truly believe that if the SHTF, surface water sources may be compromised, so I intend to use groundwater sources only, as the ground will filter out most organisms. I can then disinfect as required.
I know the WATER threads are too many, but..
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Not really worried so much about the polymers, although more on that later. Most plastic containers are not resistant enough to the sun's heat on a really hot sunny day to provide for adequate SODIS, in my opinion. No real scientific data on it, just know how little energy it takes for one of those to melt and/or burn, and how much energy it takes to kill some bacteria and viruses.
As for the polymers, there aren't so much for disposable water bottle containers, I guess, as from non-disposable plastic containers. While all of these items have been approved by the FDA, I am not entirely sure I can trust their judgement. In fact, a study in Europe last year found that repeated usage of disposable water bottles has the ability to leach endocrine disruptors (labeled in report as functional estrogens). Although if it were all I had, I still would use the disposable myself until something better came along. For using SODIS, it is my opinion that the best vessel to use is clear glass to make sure the uv has the proper intensity to disinfect. Plus, we always have a couple extras of those around.
: You know, with the wife canning and all.:
The turbidity issue can be cleared somewhat with filtering, but another option may be to provide time for particulate matter to settle and decant the pre-disinfected water to another vessel. Some of the local water supplies are less than adequate, and I have seen water that could not be seen through when from the spigot, but after approximately 4 hours, had developed a turbidity level of 5 NTU. Still not visually the hottest, but after proper filtering, the level can be taken down to less than one NTU, where it should be aesthetically pleasing.
It must be noted that some turbidity may come from algal growth....SODIS may actually excacerbate this. I would just try to steer clear of surface water with a possiblity of algal blooms when using this method of disinfection.
As for the polymers, there aren't so much for disposable water bottle containers, I guess, as from non-disposable plastic containers. While all of these items have been approved by the FDA, I am not entirely sure I can trust their judgement. In fact, a study in Europe last year found that repeated usage of disposable water bottles has the ability to leach endocrine disruptors (labeled in report as functional estrogens). Although if it were all I had, I still would use the disposable myself until something better came along. For using SODIS, it is my opinion that the best vessel to use is clear glass to make sure the uv has the proper intensity to disinfect. Plus, we always have a couple extras of those around.
: You know, with the wife canning and all.:The turbidity issue can be cleared somewhat with filtering, but another option may be to provide time for particulate matter to settle and decant the pre-disinfected water to another vessel. Some of the local water supplies are less than adequate, and I have seen water that could not be seen through when from the spigot, but after approximately 4 hours, had developed a turbidity level of 5 NTU. Still not visually the hottest, but after proper filtering, the level can be taken down to less than one NTU, where it should be aesthetically pleasing.
It must be noted that some turbidity may come from algal growth....SODIS may actually excacerbate this. I would just try to steer clear of surface water with a possiblity of algal blooms when using this method of disinfection.
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