Aquaponic Gardening

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I have been made aware of a section in the latest newsletter of an aquaponics trainer making some rather interesting statements around the risk of introducing "deadly" E. coli HO157:H7 into aquaponics systems through the introduction of worms.

 

Like most promotional material, it contains enough reference to some form of correct base statement to make their argument appear compelling, but I have found the way that the section was written distressing in many ways.  On one front, we are trying our level best to ensure food safety and hygene in our units and to educate people on the safety of aquaponic production methods.  To have someone from within the community write something down the line of "if you dare put worms in your system you run a very real risk of introducing a deadly pathogen into aquaponics" is not conducive to building a fair and realistic impression of aquaponic production methods.  Worms in media beds have been in use for many years outside of the design of the group in question, with no reports of any health issues.

 

The inference made was that (without stating how many worm growers use cattle poo) red wrigglers are likely or potentially all grown in manure from corn fed cattle and this all contains the "man made" (?????!) strain of E. coli that will then most likely survive the transfer from worm to your system where you will contaminate your crops, your family or your customers.  If you are extra unlucky, a fly from a pasture containing corn fed cattle poo will also do the trick (then why bash the worms?) if they can make the trip in under 10 seconds. 

 

The article would have had more use if it simply said something down the line of "pick your worm supplier carefully - if you are cautious about E. coli, steer clear of using worm growers that cannot guarantee that their worms were not fed corn-fed cow poo from feedlots." I do not know what the ratio is of worm producers that potentially use this feed method compared to those that do not, but if it is the case that very few follow this practice, this article borders on reckless.  Then one can write follow-ups warning people on the next one in a gazilion risk such as a bird-flu contaminated duck landing in your fish tank.  As stated before, in theory, the conditions described in the text can potentially occur. Just as, in theory, a monkey can sit down in front of a typewriter, hammer away at it and write something recognisable. Not impossible, but likely? 

 

I wrote a blog a while ago about the responsibility of perceived role models in the industry related to statements made and perceptions created from a "credible" source.  This type of statement was exactly what I was talking about.  Not worth the negativety and not worth the potential bad press and poor PR for what many aquaponic producers see as a staple - media filled beds with worms in them (is there a reason for this?).  As a scientist, I would like to see some concrete evidence related to instances of the scenario described having been observed at worm farms and in aquaponic systems.  If no such data exists, is this statement fair and accurate? Why was it made? I do not want to appear to downright rubbish their concerns, but I will appreciate a percentage risk description to back up this claim.

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Here is a link to the USDA AMS site and contact information for GAP

http://www.ams.usda.gov/AMSv1.0/ams.fetchTemplateData.do?template=T...

a couple of thousand emails to Dr. Peterson giving the advantages of aquaponics couldnt hurt


Gina Cavaliero said:

Hey Earl, thanks for the great information.  So, what you are saying is that it is the GAP guidelines we need to see revised then!  Nothing like a good challenge, huh?  Is there anywhere else that it matters that the differentiation is not made or is it just the USDA GAP guidelines that will need to change?  When you say that they are not covered by the Code of Federal Regulations, are you inferring that there is no way to petition a change? 


Earl ward said:

 Hi Gina

The problem as I see it stems from the GAP( good agriculture practices) guidelines set by USDA AMS . In the GAP guidelines it does not differentiate, the difference between livestock and aquatic animals. GAP is a voluntary program, but a lot of markets require GAP. Aquaponics cannot pass a GAP certification, the GAP is all done by 3rd party auditors just like organic certification. So in other words the 2 programs are in conflict with each other Aquaponics can be organically certified  (7CFR 207.1))because it does not include Aquatic animals in the definition of livestock; but it cannot be GAP (USDA AMS) certified. One thing else I should mention Organic certification is covered by the Code of Federal Regulations which have the same weight as law and was open to public discussion before implementation GAP was not. Every 3rd party food safety audit I have incountered follow the GAP Guidelines.

Gina Cavaliero said:

Hi Teresa, thanks for getting Bob's opinion.  That is exactly concurrent with the circumstances surrounding Friendly's food safety certification.  They had the certification for their DWC system, obviously without worms, from the state of Hawaii. However when Costco insisted that a "third party" auditor, the state, was not allowed, they had Primus come in and test for the certification.  Just like Bob stated, The problem arises in the guidelines regarding animal wastes (in this case, worm castings and fish effluent) with regard to crop production, and proximity of said animal waste to the crop production.  This was the reason they were then denied their previously granted certification.  How the state of Hawaii as an independent third party allowed the cert in the first place, I don't know.  I would assume someone with enough sense to make the connection between fish being cold blooded and not warm blooded understood that the same rules that apply to traditional ag and growing methods would not apply in an Aquaponic system.  Unfortunately the auditors for Primus translate the letter of that law, so to speak, as literally as it is spelled out and have no flexibility on it whatsoever.  That only leaves us one alternative, IMO, the rules governing food safety certification need to change to encompass alternative growing methods.  So, what that means is back to the discussion that has occured here and several times on this forum, we need peer reviewed documents in order to present facts in order to enact this change.  It is all a big uphill challenge, but I trust that eventually our industry will make progress in that direction.   It will all take time, but the growth in our industry will be paramount to us seeing that change.  Have to throw in a plug here, we need everyone to join the new Aquaponics Association, so that those numbers can amount to a voice that will be heard!  :)
Rachel you remember that when the study comes out to prove me correct. Whether or not you show a ammonia on your test strip or test tube you have ammonia in your system all the time and it is being converted to Nitrates. My thought process is it is enough to kill ecoli. Consider Chlorine in your city water will kill most bacterias and it is in the parts per million to do this. When the test proves me right you can buy me a Mai Tai Island gal. hehe.

Raychel A Watkins said:

That is our number one defense against all pathogens.  Most of the pathogens if there are any will be introduced by humans.  

some one said that E coli could not live in an ammonia based system.  We strive to keep the ammonia low so that doesn't float.  

If you are proved right on this David, I think we will all be partying all over the place.

I am about to setup a large system using only worm castings tea, made out of rabbit manure.

I had great results on experimental cultures over the last year and i did consume all production.

Do we have any update about redworms and Ecoli?

 

 

 

I haven't heard any updates.

However I believe letting the compost age for 4 months after the last addition of any manure or stuff that would support e. coli growth is a good practice for safety.

My friend Glen Martinez at Olamana Gardens raises his worms on chicken manure and sells the castings and uses them in the potting medium.  I know that he pasturizes his at a certain temp before they can be used.  He is certified organic.  I will ask him if the heating of the castings is required.  I do think it is.

Pasteurization for safety would be a way around the strict waiting period before use of the castings.  However if the castings are pasteurized you miss out on the benefits of the beneficial microbes in the castings since the heating will kill those too.

not possible, if a worm can break down harmful compounds...to simple elements...how can it transfer E. coli???

 

hahahaha

TCLynx said:

Probably have to move to a state that allows medical worms

Anthony,

    Generally it isn't a problem of the worms transfering e. coli, the problem is actually that you can't make sure every speck of material you put into the bin actually goes through a worm and then doesn't touch something that hasn't already gone through a worm so it's a matter of cross contamination.  So either you need to let the castings from a worm bin age a certain amount of time before use, or make sure you don't put anything into the bin that could cause cross contamination if you are not going to follow a strict aging timeline before use.

Good point, Thanks

TCLynx said:

Anthony,

    Generally it isn't a problem of the worms transfering e. coli, the problem is actually that you can't make sure every speck of material you put into the bin actually goes through a worm and then doesn't touch something that hasn't already gone through a worm so it's a matter of cross contamination.  So either you need to let the castings from a worm bin age a certain amount of time before use, or make sure you don't put anything into the bin that could cause cross contamination if you are not going to follow a strict aging timeline before use.

So every angler that has ever pulled a fish out of a natural stream, lake or other body of water are also playing a dangerous game with E Coli? I mean its impossible to rule out cross contamination from manure with widespread raising of livestock near streams, rivers, and lakes. Worms move they may have been exposed and they are in ALL natural eco-systems.

Something doesn't add up here.

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