Subject: Re: Compost Tea

From: Elaine Ingham <[email-masked]>
Date: Thu, 24 Oct 2002 19:05:20 EDT

There have been questions about the National Organic Program regs on compost
tea, so let me offer some perspective.

The National Organics Standard Board appointed the Compost Task Force to
write the regs on compost.  The task force was also given the task of writing
the compost tea regulations.

Apparently, the Compost Task Force chairperson, Eric Sideman, called two
people, Wil Brinton, and Pat Milner, and on the basis of their opinions,
wrote the regs on compost tea.  Initially, the recommendation said that
sugar, molasses, barley malt and soluble carbon materials could not be used
in compost tea, because E. coli would grow if these materials were in the
tea.

Why was this reg put together?  Where did that come from?  Is it meaningful?

First of all, who are Wil Brinton and Pat Milner?  Wil had given up on 3-week
anaerobic compost teas  because he could never get rid of the E. coli.  Pat
Milner has never made compost tea, that I am aware, but had funded two
studies on compost tea.  The studies were performed at the USDA lab in
Albany, CA by a student of Dr. Subbarao's,  whose background is in the
pharmaceutical industry, and the second study was done by BBC Labs, run by
Ms. Vicki Bess, who has a Master's degree in microbiology.  Neither has
experience with 24-hour compost tea.

Dr. Subbarao's student, Brian Duffy, took E. coli-containing organic matter
(compost can't have E. coli under the USDA NOP regs, so it wasn't finished
compost.  And according to the source of the "pre-compost material", it
wasn't finished compost).  The E. coli-containing material was placed in
flasks, the flasks sealed and incubated for 24 hours.  E. coli was detected
in the material they sprayed on plants the following days.

This study has nothing to do with compost tea.  No compost tea maker is
sealed shut.  No one makes tea that way.  There is absolutely no evidence
here that aerobic compost tea could cause a problem.  This was a study that
was a waste of tax-payers' money.

BBC Labs took the same E. coli containing material, put it in a Growing
Solutions machine that always goes anaerobic in the basket during the tea
making process, added sugars, molasses, and barley malt, and found E. coli
growing in the 24 hour brew.

First, the "compost" contained E. coli.  Second, this particular tea machine
always goes anaerobic in the basket, and thus sets the stage for the growth
of E. coli, because the E. coli can out-compete the aerobic, beneficial
organisms when oxygen is low.  Third, the addition of sugar, molasses, barley
malt probably got the bacteria growing so rapidly that they used up oxygen
which helped the E. coli out-compete other organisms.

The paper published by BBC Labs in Biocycle (not a peer-reviewed journal) had
data on temperature and oxygen.  The temperatures cited ranged from 21 to 27
C.  The oxygen concentrations reported by Ms. Bess were between 10.1 to 10.9
mg oxygen per liter.

It is NOT POSSIBLE to have these levels of oxygen in water at the
temperatures cited.  Consider too that the elevation of Tempe, Arizona means
the oxygen concentration is even more impossible.  Check the maximum
concentration of oxygen in water on the US Geological Survey website.   These
concentrations are NOT POSSIBLE at these temperatures and elevations.  Unless
the air was pressurized, and there is no mention of that in the paper.  Water
holds less oxygen as temperature, or elevation, increase.

I contend that Ms. Bess did not in fact measure oxygen in the tea brew that
BBC Labs reported on.  The oxygen data were probably from work done by the
manufacturer, in Oregon, in the winter, at basically sea level.  The oxygen
data fit Oregon winter conditions.

There are no data to support Bess' contention that the tea stayed aerobic
through the whole brew cycle.  But there's no way to know, actually, because
they could not have measured the oxygen on the tea run where E. coli
occurred.

Thus, the "data" on which the Compost Task Force based their recommendation
were flawed.  With or without sugar, molasses or soluble carbon materials,
there was no evidence that E. coli would occur in tea.  All our data indicate
that as long as tea is kept aerobic and numbers of bacteria and fungi are
high and actively growing, no E. coli will be detected, or only at very low
levels.  All tea machines that get good fungal growth must remain aerobic.

I have been told that Vicki Bess says that the Growing Solutions tea maker
"super-saturates" the water with oxygen.  If that was true, then E. coli
would not have been detected, because E.coli cannot withstand highly
oxidizing conditions.   In fact, no one I know who owns the Growing Solutions
tea maker has obtained the high oxygen concentrations that the manufacturer
shows on the web site.

There's a serious discrepancy here.  Until someone else can repeat the same
results, i.e., show the tea maker stayed aerobic through the tea brew, and E.
coli was still in high numbers at the end of the brew, this study has to be
viewed as not scientifically sound.

Ms .Bess says that she has data showing that E. coli grows in aerobic
conditions.  E. coli can grow in aerobic conditions in the LAB, where we grow
the organism in very specific conditions that allow E. coli to grow in
aerobic conditions.  If there are a reasonable number of aerobic organisms
present, E. coli will be out-competed for food and space.  Protozoa in the
tea will consume E. coli.  In aerobic conditions, with high numbers of
competitors, predators and inhibitory compounds produced, E. coli does not
survive.

If E. coli did grow in aerated conditions found in sewage treatment plants,
E. coli would be everywhere, on everything.  But it is not, so clearly,
aerobic conditions, with lots of competitive, inhibitory and consuming
organisms present, will take out the E. coli.

Why do we get concerned about E. coli?  Because if E. coli is present, it
means there is contamination by fecal material where sooner or later there
will be a human pathogen present, and then we have disease.  So, E. coli is
an indicator of a problem, not something to go nuts about.  There's a
problem, work to fix it.

Pathogenic E. coli is not likely to occur if healthy animals are making the
manure.  It is much more reasonable to make a regulation about the kind of
manure that can be used, that testing of the compost has to be done to
document no E. coli, or that the tea brew has to stay fully aerobic so E.
coli is taken out than say all compost tea is dangerous.

Do we have data showing that E. coli does not survive in aerobic conditions?
Yes.  We submitted that data to several people who were at the NOSB meeting.
Did they present that data?  Not that I'm aware.

A week before the NOSB meeting, Wil Brinton sent an e-mail to the
[email-masked] list serve.  He basically told us about the deal
he had tried to make to keep compost tea in the NOP rules.  The ruling about
sugars came from him, apparently.  If that rule had been adopted, we would
not have been able to put compost in the compost tea, because compost
contains soluble carbon materials.

So, it was a non-choice.  That poorly written, not-supported-by-the-data
recommendation had to be removed.  But what was it replaced by?

Wil Brinton apparently decided that compost and worm compost tea cannot be
used on foodstuffs because of the possible danger that E. coli may be
present.  But there is no evidence to say there is a danger with properly
made compost tea.  All they had to put in a regulation was that compost tea
made from compost without E. coli present in the compost was acceptable.  If
made with E. coli-containing materials, the tea had to be kept aerated, and
have plenty of competing bacteria, fungi and protozoa.  We have documented
the reduction in E. coli, and thus in any human pathogen, in properly made
compost tea.

For the NOSB to accept a recommendation based on incorrect studies, studies
to peer-reviewed, not published in any scientifically peer-reviewed journal,
using only one poorly designed tea machine, or sealed glass flasks, is just
unbelievable.   The data on sugars causing E. coli to grow in aerated tea is
silly.  The data in the paper clearly show that the oxygen data are not
correct.  It is very likely that the tea did not stay aerobic.

We have repeated a number of studies showing that E. coli does not survive in
aerated tea with adequate competitive life.   Starting with "composted"
manure with an average number of 44,000 E. coli per gram of manure, the E.
coli present at the end of an incubation with molasses and kelp in the brew,
was 2.7 E. coli per ml of tea.

This is less than E. coli levels allowed in irrigation water, and irrigation
can be done up to the time you pick your crop.  Why is organic agriculture
being held to a higher standard than conventional crops?

The development process for National Organic Program regulations has been
poor.   The people appointed to write the recommendations did not do their
jobs in a number of cases.  A conversation with two people who don't have
expertise on 24 hour compost tea wrote the regulations?  The Compost Task
Force should have researched the conditions that allow E. coli to grow, and
should have known that anaerobic, or reduced oxygen conditions, are required
for E. coli to grow and survive.  Aeration result in the death of E. coli.
High oxygen concentrations kill E. coli.  Talk to sewage treatment people.

We were almost saddled with a really stupid regulation about no sugar in tea.
 Then instead of doing their job once the first objection to the lack of
science forced them to rescind the recommendation, they wrote a regulation
that compost tea can't be used because of the fear of E. coli.

I can put manure in coffee makers, and make a brown liquid that looks like
coffee.  Is anyone suggesting that coffee makers should be dis-allowed
because someone could be stupid and put the wrong stuff in a coffee maker?

Of course not.  The regulations should be written to state the conditions
that allow safe compost tea to be made.  Aerobic through the whole brew
cycle.  Lots of good aerobic bacteria, fungi and protozoa growing to compete
with, inhibit and consume the E. coli.
That gets rid of the E. coli and human pathogens.

If there is no E. coli in the starting materials, then why say there's a
danger of E. coli.  At least compost tea made with non-manure materials
should have been allowed.

But no, no tea at all can be used.

Anyone else feel like there's a hidden agenda here?

Elaine Ingham
President, Soil Foodweb Inc.
Director of Research, Soil Foodweb New York
President, Soil Foodweb Institute, Lismore, Australia
Director of Quality Assurance, Soil Foodweb Europe, The Netherlands