Hello,

I am journalist studying the question of the use of polymers in soil
conditioners such as Terracottem.

The company (see www.terracottem.com) says it is non-toxic, but is that
really so? How sure can we be?

Other question : this soil conditioner is highly expensive, supposedly so
because of the price of non-toxic polymers : can that be be true, or is that
fake excuse for selling their product at as high a price as possible (a
pity, since it could be a solution for erosion and drought problems in arid
regions - which, as we know, are most often poor).

Don't know if I came to the right person with this question, but would be
most thankful if there would be a reply or piece of advice....


F (brussels, Belgium)

The potential toxicity of hydrogels is not something that a botanist
would have the expertise to answer. The company Download page has a
Material Safety Data Sheet (MSDS) which lists some toxicity tests on
fish and bacteria. The chief hazard would seem to be possible
inhalation of dust during handling. That can be avoided with proper
equipment. Any toxicity would be much more likely to affect the
factory workers or workers who apply the material to the soil than
consumers of crops produced in hydrogel amended soil.

The bigger question is whether the material is effective and cost-
effective. The company webpage on History shows three photos of a
field supposedly improved by hydrogels. However, there are no photos
of a control field that received no hydrogels. Thus, there is no way a
scientist can judge the effect of the hydrogels. There are also no
numerical data indicating the percent increase in biomass with
hydrogel compared to no hydrogel.

From a scientist's perspective the company website is very vague. It
says the product significantly improves plant growth and soil water
content but provides no numbers, i.e. is it 1% or 10%? Does the yield
increase pay for the cost of the hydrogel?

It strikes me as odd that if the product is so effective for
subsistence agriculture in arid areas, why is the website only
marketing it to for mainly aesthetic uses such as sports turf,
landscaping, horticulture and home and garden.

The site has a section for press clippings, although none are listed
there. Where are peer-reviewed scientific articles evaluating the
product?

Potassium hydrogels also act as a potassium fertilizer so the control
treatment must also supply the same amount of potassium. Was this
done? This product also contains substantial amount of "NPK
fertilizers and trace elements." Are the effects mainly due to the
fertilizer or the water absorbent properties?

The claim that this is a proprietary mixture of polymers begs the
question of how many combinations were field tested before coming up
with the ideal mixture and how much more effective is the mixture
compared to existing single hydrogels?

I know of a research study that evaluated a hydrogel used in container
growing media. The study found that for about the same cost, organic
matter could provide the same amount of increased water holding
capacity as the hydrogel.

There are other low tech methods of conserving soil moisture such as
mulching, adding organic matter to soil and fallowing fields between
crops. Is hydrogel more cost-effective than these techniques?

Google scholar can be used to locate scientific articles on hydrogel
effects on soils.
http://scholar.google.com/scholar?hl...il&btnG=Search

David R. Hershey, Ph.D.
http://www.angelfire.com/ab6/hershey/bio.htm















On Nov 17, 11:55 am, "fedrik de beul" wrote:
Hello,

I am journalist studying the question of the use of polymers in soil
conditioners such as Terracottem.

The company (seewww.terracottem.com) says it is non-toxic, but is that
really so? How sure can we be?

Other question : this soil conditioner is highly expensive, supposedly so
because of the price of non-toxic polymers : can that be be true, or is that
fake excuse for selling their product at as high a price as possible (a
pity, since it could be a solution for erosion and drought problems in arid
regions - which, as we know, are most often poor).

Don't know if I came to the right person with this question, but would be
most thankful if there would be a reply or piece of advice....

F (brussels, Belgium)

Shah Polymers developing and marketing, Suppliers of Engineering Plastics, Polyacetal (POM), Polycarbonate, Polyurethane (PU), Polymers, Acrylic, Acrylonitrile Butadiene Styrene (ABS), PVDF Suppliers, Styrene Acrylonitrile (SAN), PolyUrethane (PU), Ethylene Vinyl Acetate (EVA), Poly acetyl, K Resin (NSBC), Nylon (PA 6, 66), manufacturing and marketing superior quality Polycarbonates Sheets for the building and construction industry in Bangalore, India.Polyacetal (POM), Polycarbonate, Polyurethane PU, K Resin (NSBC), Engineering Plastics, (SAN) Styrene Acrylonitrile, (SAN) Styrene Acrylonitrile, Ethylene Vinyl Acetate (EVA), Acrylonitrile Butadiene Styrene (ABS), Nylon (PA 6, 66), Acrylic (PMMA), polyvinylidene fluoride suppliers, Shah Polymers, Manufacturers, Bangalore, India.

When discussing a topic like this, one first needs to establish “what” we are discussing. First of all, TerraCottem (there are 3 types: TerraCottem Universal, TerraCottem Complement and TerraCottem Turf) is not a hydrogel, but a soil conditioner. It contains, amongst others hydroabsorbant copolymers (appr. 40%). This term “copolymer” is very important in this regard. This is a 3D molecule of 2 different polymer types, making it extremely stable. One should now that polymers (and I am talking about suitable polymers for plant growth purposes!) aren’t toxic. The only danger lies in the amount of monomers (which are the building stones of the polymers). During production, these monomers are turned into polymers. The TerraCottem polymers are further joined into copolymers. That way, the copolymers can’t degrade into their building stones. As a Belgian company, TerraCottem is under the control of the Federal Agency for the safety of the food chain (FASFC). Their products are guaranteed non-toxic. However, I have no doubt that on the market there are polymers (again, TerraCottem is a soil conditioner containing copolymers) which are toxic in some way…
Secondly, on the MSDS of the TerraCottem products there indeed is a paragraph on dust formation. However, this has nothing to do with the copolymers which come in a granular form. TerraCottem Universal and TerraCottem Complement both contain volcanic rock (lava). During mechanical handling (mixing, spreading) some dust can be formed because these granules can break down into smaller particles.
Thirdly, when talking about cost-effectiveness one indeed must compare with some kind of control object. Ten years of testing, both in the laboratory and in the field, were completed before the product was made available commercially on an international scale in 1993 (the 3 pictures mentioned in this topic are taken during this product. I guess that the desert counts as a control? No plant growth was possible before TerraCottem application…). Once the effectiveness of the product is established (and this goes for any commercial product), one does not necessary needs to consider a control object when applying the product for commercial purposes. Who does fertilise only half of his lawn to see whether the fertiliser is effective or not? ;-) Many of the scientific reports are available at the company if one takes the time to contact the commercial department. Furthermore, the company’s R&D department still carries out its scientific work in conjunction with independent research facilities ensuring its clients that the TerraCottem soil conditioning technology remains at the forefront of the industry at the most cost-effective price.
As a scientist, I can understand the remark that the company website is somewhat vague on scientific data. However, this is a commercial website, not a scientific one. And as mentioned before, scientific data is available on demand. What to post on the website: results on plant X1 with Y1 gram of TerraCottem, in soil Y1? This will raise the questions: “what about plant X2?”, “Y2 grams of TCU?” and “what happens in soil Z2?”.
The fact that the company focusses primarily on tree & shrub planting, grass/turf, flower beds & hanging baskets, etc… is a commercial decision.
I count over 80 press articles on Discover the press articles on the TerraCottem leading soil conditioning technology....