Fungicides, antibacterials (was --Re: [compost_tea] The toxic part of aloe)

From: Ted Peterson <ted.peterson_at_tcsn.net>
Date: Mon, 3 Nov 2003 16:49:01 -0800

I have done some investigation into the bacterial and fungal growty possibi=
lities of aloe. While I can find a great deal of information and scholarly=
/nonscholarly research into the restorative and healing properties of aloe,=
 I can find nothing that would lead me to believe that aloe added as a nutr=
ient would enhance aerobic bacterial/fungal growth.

An interesting investigation into additives and systems:

I found some tea brewers using recycled tire rubber for aeriation. I had a=
 similar idea about two years ago. Pursuing this, I did some investigation=
 and found Dr. Alison Draper who was conducting post-doctoral research into=
 tire rubber constituents, water soluability and birth defects . She found=
 positive correlation between the breakdown of tire components (a lot of an=
tifungicide/antibacterials found in tire formulas) and the amount of these =
same components showing up in drinking water.

It turns out that many of the components of tires are water soluable. I kn=
ow tires are supposed to withstand rain and such but tires are made with a =
lifecycle and water is one of the components that will break down compounds=
 in the tires which will eventually lead to a breakdown of the tire.

Some of the components are broken down by heat. So the friction of the tir=
e against asphalt will send molecules onto the air which eventually end up =
in water. Some of the compounds are designed to be broken down by bacteria=
 over a long period of time which is why antibacterials are added to the ti=
re compound mix. By the time they become active, the tire is sitting in a =
dump, theoretically.

So I started thinking about how nitrogen breaks down almost everything. Ev=
erything rusts or rots on a farm and it's not because of lack keeping equip=
ment clean. I asked myself if the addition of O2 and nutrients (NPK source=
s) to the tea could break down the recycled rubber and put harmful molecule=
s into my resulting mix. Emails with Dr. Draper and a phone call seemed to=
 support this idea and I dumped the recycled tire rubber idea.

Before this, I made some test batches using soaker hose as an aeration medi=
um. I got correct readings (DO meter) at correct time and the tea "behaved=
" as it should. So it's possible that even though there are antibacterial =
elements, the amount of bacteria grown overwhelm the anti compounds. The s=
ituation could also be that the bacteria grow quickly to register results b=
ut die just as quickly. There is no way to be 100% sure. So I would rathe=
r err to the side of caution.

According to Dr. Draper, some of the compounds (in the form of molecules) g=
iven off by the tires are extremely harmful. They are as harmful as Clopyr=
alid, found in most yard waste (often used in composting), which is toxic a=
t 1 part per billion.

Now, what was the result of this? I found a different medium for aeration.=
  (Dr. Draper eventually was attacked by the tire industry. Much of her re=
search was brought into question but none of it was directly refuted. She =
eventually lost her research grant and is now coordinating an environmental=
 media center in Tennessee.)

Back to aloe:

I am very sensitive about adding anything to the tea and am careful about t=
he compost I use. I keep reminding myself and my customers over and over t=
hat compost tea is not fertilizer even though the tea may contain some slig=
ht amounts of NPK. I try to keep inputs to a minimum so unless I get some =
real hard data concerning the use of aloe I will refrain.

Ted Peterson
Earth-Wise/Spirit of the Earth




Received on Mon Nov 03 2003 - 22:43:22 EST

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