There are about 70,000 water utilities in the US. They only do
pathogen tests on demand. Current technology makes the costs of
continuous testing prohibitive.
If broad, meaningful test could be done at a low cost, this would be a
For now, it is sampling only, test on demand. If the sample storage
is questionable, this should really be addressed.
On Sat, 8 Dec 2001 14:00:27 -0000, "Des O'Connor"
<des at micro-search.com> wrote:
>>I think the value of the storage tactics you mention may be low.
>>Bacterial waterborne pathogens such as gram negative rods for example have
>realtively short but variable half lifes in stored water samples.
>>Chilling or freezing may oprate to produce non recoverability. Such factors
>would therefore cloud any epidemiological effort.
>>While a few know water bourne pathogens ( some viruses, spores etc) may
>surive extended retention under the stroge conditions mentioned I would
>suggest most would not.
>>If there is risk to public health in your area then adivse your funding
>authority to get their ethics in and stop putting human health at risk.
>>Hope this helps.
>>>><rtjoseph at ev1.net> wrote in message news:3c116bd5.157446750 at news.ev1.net...>> I am looking for comments and references to sampling water across a
>> municiple water distribution system.
>>>> In order to determine the source of infections, it is suggested to
>> sample points across the distribution system and store them from some
>> time. If an outbreak of a disease occurs, the samples may then be
>> tested to see if water distribution system contributed to the spread
>> and how. (Regular testing all samples is usually considered too
>> expensive as the occurance is believed to be so low.)
>>>> How long can a sample be considered viable for testing if sealed in a
>> bottle and shelved? Is refrigeration or freezing more appropriate?
>> Are there standards for such sampling and holding?