I'm not sure about water, but I know that glass and plastic can stop some UV
rays. If your container is stopping the UV the water may or may not be
contributing to the stoppage.
--
John Gentile Rhode Island Apple Group
yjgent at home.com President
"I never make mistakes, I only have unexpected learning opportunities"
> From: Sergio <sergioal at bbm1.ucm.es>
> Organization: UCM
> Newsgroups: bionet.microbiology,sci.bio.microbiology,sci.geo.oceanography
> Date: Wed, 21 Mar 2001 21:20:42 +0100
> Subject: Re: Ultraviolet Ecolgy
>> Hi Matt,
> what you said about the UV penetration in water is just the opposite i always
> was told.
> We perform UV mutations very often (as part of the practices for our students)
> to show the viability reduction.. have you tried to do this kind of
> experiments
> placing a water container between UV source and plates?. I guess the water can
> acts as a UV shield, but never tried.
>> Sergio
>> Matt wrote:
>>> There are actually quite a lot just suspended in the water column -- a
>> decent oceanic average is about a million per mL! It was generally thought
>> to be quite low, because the assay used was the standard plating out to see
>> how many CFUs form, but at least 90% of marine bacteria will not grow in
>> culture. Since UV can penetrate quite well in water (very significant in a
>> least the first few metres), UV radiation accounts for a significant amount
>> of bacterial damage and mortality (parallel with UV induced viral lysis).
>>>> Interesting stuff!
>>>> Matt
>> UBC Department of Biology
>