[USCC] FW: Re: Fecal Coliform testing issues

[frank]

Tim,
You are a great source of information and I agree with your assessment 
of ECo157 below. At the end of composting (point of sale) we no longer 
have an indicator organism to use and the only method of determining if 
a specific pathogen is present is to test for it. I suggest we (USCC) 
should test every compost for EC o157 for, say a year, just to see where 
we stand. The USCC has a Chain of Custody form that has a check-off-list 
for the feedstock so when we compare the EC o157 results with feedstock 
we may be able to determine the feedstock of most concern if we find it 
at all..

Thanks
Frank


>
>Frank
>
>In a large research program 
>UKWIR (2000) Methods for detection of pathogens in biosolids.  Report ref.
>00/SL/06/05.  UKWIR, London 
>UKWIR (2002) Pathogens in biosolids the fate of pathogens in sewage
>treatment.  Report ref. 02/SL/06/6.  ISBN: 1 84057 2612  UKWIR, London
>UKWIR (2003) Pathogens in Biosolids - Microbiological Risk Assessment.
>Report ref. 03/SL/06/7.  ISBN: 1 84057 294 9 UKWIR, London
>we found E. coli O157:H7 was no more resistant to composting and other forms
>of treatment than other indigenous E. coli.  Cultured lab strains were
>different - they were more susceptible to treatment.  
>
>However, since the infective dose of O157 is so low for humans and the
>effects so dire my approach (consistent with HACCP) has been to look at the
>source of material being treated.  If it is animal manure (cows or sheep)
>the chances that it contains O157 are high because a high proportion [10%?]
>have symtomless infection and are shedding log-8 per gDS.  I would therefore
>be very careful about the treatment if the product of treatment is going to
>be handled or to be in contact with ready-to-eat crops, etc.  If I were
>starting with manure and the product was intended for a 'high risk' use, I
>would validate the process by testing for O157 - for broad acre agriculture
>(grains, etc.) it is not really an issue because there is a second barrier.
>
>regards
> 
>
>Tim
>
>
>  
>

-- 
Frank Shields
Soil Control Lab
42 Hangar way
Watsonville, CA  95076
(831) 724-5422 tel
(831) 724-3188 fax
frank at compostlab.com
www.compostlab.com