here this might be some help, its a copy paste.. just read this its crazy and all makes sense
By now some at least reading this post will have at least heard of the Offgassing effect within grow tents being reported throughout the internet. This is a confirmed effect admitted to by at least one manufacturer of these tents, however it is obvious with the amount of problems occurring from various suppliers that more of these tents are affected than is being admitted to by manufacturers.
If you are growing plants in one of these tents that is affected your plants will be displaying signs that you are chasing between over fertilising and nutrient deficiencies in what is a swing of a very small margin. Currently there is two threads at least displaying the signs of the Offgassing problem. The margin from one issue to the other can be very small indeed I have seen plain tap water with the PH set result in the plants displaying a N deficiency and then when .5 ml per litre of Canna Aqua Vega is added to the hydro solution or equivalent Terra product to the the same water for soil mixes within a day the plants display signs of over fertilisation and are burned. Even Superthrive at 25% strength caused the plants to burn.
The obvious sign is the washing out or yellowing of the leafs, this has been seen in other pictures to get as bad as to make the leaf look almost white before turning brown. This can occur as early as the first few sets of leafs and has been seen to start within the time the plant reaches three sets of nodes. The main stalk will often not develop fully and along with the branches can be thin and fragile. Roots are also affected both in soil mixes and hydro set-ups and also in both set-ups when cutting down plants they are found to be hollow throughout as the pith refered to in the relating text of the plant cross section below is eroded.
HydroHut
At the moment only one grow tent manufacturer as openly stated that they have a problem that being Hydrohut. The statement copied below is an open letter from the makers of Hydrohuts as basically a recall of there product.
Quote:
Open Letter from HydroHut to the public
In the last several months, HydroHut has been made aware of and pursued a problem with some of its Huts causing a peculiar plant yellowing leading to plant whitening in certain, sensitive plants. While the issue did not arise in all plants, or all Huts, the existence of a problem was not conducive to our product’s mission.
After several months of extensive testing, false positives and much interaction with the public regarding this matter, we have found an EPA approved compound that isn’t stable in our plastic and that causes extreme stress to certain sensitive plants. In the future, this compound will be removed during manufacture.
Our focus has been directed at how to remove this compound from the plastic and to do so in a way that we could retroactively repair any HydroHut already in the field. As of February 2008, HydroHut will be repairing any affected HydroHuts at its facility. The exact process by which we repair the HydroHuts is extensive and proprietary and it will be carried out by a trainedstaff at our locations.
We fully understand that this situation with our product has adversely affected many clients. For this reason, we are standing behind our product and are offering anyone who has been affected a way to have his/her HydroHut repaired free of charge.
Any client, be they end user or store, can arrange to have his HydroHut shipped back to our Los Angeles facility for processing, free of charge. The HydroHut will then be shipped back to the client free of charge.
All inquiries for HydroHut processing should be directed to
hydrohuts@gmail.com with no exceptions.
Please provide the following details in the email:
1) Size/model of affected HydroHut
2) Number of affected HydroHuts (only the HydroHut brand will beaccepted for processing)
3) Address where the HydroHut can be picked up by UPS call tag (make sure someone is there to meet the UPS driver) Do not use a PO box as UPS will not pick up from a PO box
4) A name to whom/which we can address the package going back to you, the client. (We will make a good faith attempt at getting your product back to you. If nobody is at the address to accept the package three times, the package will be sent back to Los Angeles. Any further attempts to get the package to the client will be paid for by client.)
5) Please remove your HydroHut canvas or skin and box it up. Do not pack up your poles or hardware. Do not remove your frame. Do not attempt to ship us your frame or other items. We will only be call tagging the canvas in a box. You must provide that box and properly seal that box. We will send you a call tag for a specific weight based on the email you send to us with your HydroHut details. Again, we will only be taking back your canvas for processing; no other parts or hardware will be accepted. Leave your frame set up and intact.
6) We will make every effort to process and reship your HydroHut canvas within two weeks. This is not a guarantee but it is our goal. Please note that ground shipments across the USA can take up to 8 days! Even if we process your HydroHut in only one day, there could still be 16 days of ground shipping, 8 days coming to us and 8 days going back. Be patient. Most clients will not have towait two weeks. Every attempt will be made to expedite each HydroHut.
7) If a store has new HydroHut, still in its original box, the canvas can be re-boxed in a separate box, and the canvas will be returned to the store new and folded, ready to put back into the original box. Please keep your original box at your store including all poles, hardware, and instructions. Do not send us the entire unit.
While this entire exercise may be time consuming, HydroHut is doing all that it can to rectify this problem as quickly as possible. We apologize to everyone for the difficulties incurred with our product, end-users and stores. Without a loyal standing of clients we would be nothing. It is our goal make this situation as right as we can. Thank you to everyone who has stuck with us through this difficult period.
Evan Townsley
Managing Director
Follow up information provided by discussion with thanks
Quote:
HydroHuts encountered a toxic plastic issue related to some plants in their tents. The manufacturers have refused to come clean with what they did in China and asking them again for months led to no divulging of the truth. As we knew that the same machine manufactured for many brands, we assumed that other brands would come forth and admit a problem as we did, but that was not the case.
Tracking down the culprit did take several months. The culprit has been sought before, 3 times to be exact but most of those years were pre-internet days and the word did not get passed around. Let us hope that our disaster and bad fortune will now lead to everyone knowing what to look for if these toxic plant symptoms ever reappear around the world.
We at HydroHut have been well bashed for incurring this problem and unknowingly passing it on. It appeared in our product two years after we began selling our HydroHuts so definitely something was changed behind our backs, but we took responsibility.
Our recall ran most of 2008 and included arranging credit for those clients affected who returned their HydroHut to the authorized store of purchase. The recall finished on December 31, 2008. We are now selling a new, non-toxic and much improved HydroHut.
Following please find a letter with a link to the actual problem and how it was studied at 3 different points in the second half of the last century and several other links talking about the plasticizer/phthalate issue itself and those effects on plants and humans as they differ greatly.
HydroHuts USA
Suplemental information provided by Hydrohut
HomeBox
Homebox claims its products are not affected by the Offgassing because they use a different plastic product to make their tents namely Polyethylene (PE) and claim that it is PVC based tents that are affected.
Quote:
Lately, we have had an increasing number of customers and retailers approaching us with questions and concerns about some problems they have heard of with grow boxes. Some were simple problems like the cover material becoming brittle with use or a strange smell to the boxes when they are new (due to outgasing); other problems ranged from weird, complex to some that were a bit frightening like plants yellowing and dying within the grow boxes. Everybody wanted to know if these things could happen with an Original Homebox as well. The answer is "No."
How can we be so sure? Let me explain.
Our Homeboxes were on the market for over 3 years before the first imitations appeared. In that time we have not received one single complaint. And, we can assure everyone, that all these problems will definitely not occur with any of our products which are of the highest quality.
When starting the inventing process of the portable grow box we named Homebox, finding the perfect material needed for the cover was a huge issue for us. The demands were set fast:
• Durable and tough but not too heavy
• Lightproof
• Reflecting inside
Soon it was clear, that it had to be several materials, combined to one. Looking only at these perimeters, Polyvinyl chloride (PVC) seemed to be the best solution, followed by Polyurethane (PU), which has very similar properties. It is easy to laminate, tough and relatively cheap.
But we also had clear demands concerning the protection of:
• The users and consumers health
• The environment
Now, looking at these factors, both PVC and PU were instantly not a choice any more.
We researched a lot, and after long time and many investments into trials and tests, we found the perfect combination for our Material.
It consists of 3 layers:
• on the outside we use webbed Polyamid (PA), for strength and durability and to make sowing possible
• as a middle layer, we use black Polyethylene (PE) to guarantee that it is lightproof
• the inner layer is white PE to ensure maximum reflection and perfect ability to clean
Why did we choose to use PA and PE instead of PVC or PU? And why is that so important in reference to the occurring problems?
To explain that, let us peek a bit into material science. What are the different characteristics of PVC, PU; PA and PE?
Additional information supplied via discussion with thanks
Quote:
please take your time to look up the test report, which is posted on our website. is is also mentioned in the first post of the thread.
this test repost is done by
www.sgs.com.
they are a world wide reputated neutral test lab.
the report clearly says, that our material does not contain any measurable harmfull dyes, metals, nor phtalates. well, it contains 8mg/kg barium. BUT, the hardest limit (also stated in the report) is 1000mg/kg of Barium. so we are WAY BELOW the strongest restriction out there for household goods, or even children toys.
What regulations and limits are we refering to:
read our test report, and you also get the details of what SGS is referring to, when giving limits. or what they based their test criterias on.
it is very scientific, but well, thats what is is: science. correlated to regulations from US and EU laws.
for example: pg 4 of the report: the refer the german food laws: LFGB § 64 BVL B 82.02.2 and .4
EU DIRECTIVE 2005/84/EC (Toys safety)
page 5 metals: it refers to EN 71 PART 3 (migration of elements (metals) : toys safety): the limits are given there as well as our materials test results.
i have to raise another issue: even if other tents DO NOT kill plants, they might harm the organisms being around it over long term. metals like lead, cadmium, etc, phtalates (softeners) might all migrate over long term. they then accumulate in plants (consumables??), and with that, in humans. so even though your box might not kill plants instantly, it might still poison you over the years. ever heard of lead poisoning, e.g.? worth investigating...
There full explanation along with a link to their test report can be viewed at
http://www.homebox.net/dhtml/nopvc.php
This claim that PE is better than PVC seems somewhat supported by information on the Greenpeace site for alternatives to PVC.
http://archive.greenpeace.org/toxics...abase/bad.html
Quote:
Why PVC is bad news
Globally, over 50% of PVC manufactured is used in construction, in products such as pipelines, wiring, siding, flooring and wallpaper. As a building material PVC is cheap, easy to install and easy to replace. PVC is replacing ‘traditional’ building materials such as wood, concrete and clay in many areas. Although it appears to be the ideal building material, PVC has high environmental and human health costs that its manufacturers fail to tell consumers.
From its manufacture to its disposal, PVC emits toxic compounds. During the manufacture of the building block ingredients of PVC (such as vinyl chloride monomer) dioxin and other persistent pollutants are emitted into the air, water and land, which present both acute and chronic health hazards. During use, PVC products can leach toxic
additives, for example flooring can release softeners called phthalates. When PVC reaches the end of its useful life, it can be either landfilled, where it leaches toxic additives or incinerated, again emitting dioxin and heavy metals. When PVC burns in accidental fires, hydrogen chloride gas and dioxin are formed.
Opinion
My opinion on this problem is that at present no grow tent can be trusted and it should not be our responsibility as the consumer to prove whether or not products we buy are safe. Given the issues that are widespread across more tent manufacturers than have so far admitted to it. It is now incumbent upon this industry to test and prove the safety of their own products using international standards set by the FDA, USDA, Canadian & EU governing bodies along with any other applicable. I would also recommend that all those selling these tents review whether they want to be involved in the distribution of a product that could lead to health risks in the population. At least the cigarette provision was done with most end users being aware they posed health risks and we have seen how many court cases have been raised once the risk to health was confirmed by external sources. I currently still have a tent that is affected by the Offgassing issue and I am considering the options along with costs to have it tested. I would be prepared to make samples of it available for independent third party testing.
The bottom line is if you are using a grow tent and have never previously had a successful grow in the tent then you need to get rid of it as your first option in trying to recover your plants not your last.
Revision I (always prepared to revise my opinion as new information is available)
From discussions it is apparent that plastic product grow tents are not applicable to receive designated marking although Homebox at least recognises that this would not be a problem for them and would provide benefits to both the suppliers and the consumers. In the situation at the moment the best that can be aimed for is that plastic products meet the safety standards for childrens toys etc... under the EU Directive.
EU DIRECTIVE 2005/84/EC (Toys safety)
This can be viewed using this link eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2005:34 4:0040:01:EN:HTML
Paste it into a new tab / window as its an EU government link and probably best not to have an active link back.
Revision II
A lo of good info provided which seems to support the assertion PVC is not a good material for use alongside plants.
It is a distraction from the real issues to continue using the offgassing issue as a reason to bash Hydrohut in particular. From a consumer point of view yes there was an issue, yes an offer to solve the problem was made and yes it was carried through therefore there is no reason any institution like trading standards would consider they have acted in any way other than properly.
The ongoing issue is with those brands who may discretely accept the issue on an individual basis, but are not publicly stating so. Also those still selling the same product as a quick search on a popular auction site would list hundreds for sale.
I still think as someone without a degree in plastics or materials that since these issues are obviously known to the scientists who do develop these products that a product mark to signify materials do not off gas. Developed by the industry as a self regulatory standard would be a good idea. Even better if it was an EU and equivelant regulatory requirement.
Cross Section Image
This is an image of the hemp but with the genus similarity the same image is valid for cannabis IMHO.
http://www.hempology.org/ALL HISTO...GE HEMP.html
Quote:
A thin cross-section cut from the stem of such a plant exhibits the characteristics in Fig. 7, in which A is the cuticle or outer bark, B is the woody part, and C the pith. The fibrous layer is between the two dark circles D, and a few groups of fibres in this layer are indicated by the letter E.