# lexan top



## Kalakole (Jun 30, 2011)

I was wondering if anyone had any experience with lexan tops? I want to know if they bow or not and what thickness you use. I couldn't find a thread on it :/


----------



## Pumilo (Sep 4, 2010)

Lexan is known to leach dangerous compounds.

Plastics made from polycarbonate resin or Polyethylene Terephthalate (PET) tend to leach out a potent hormone disruptor called Bisphenol-A (BPA). BPA, a chemical found in most plastics impairs the reproductive organs and conduces adverse effects on breast tissue development, prostate development (reduces sperm count) and tumors. This chemical leaches out into the contents of the water bottle during the normal wear and tear of the bottle. 

Plastic Bottles Health Hazard

Acrylic lids will warp unless design measures are taken to try to prevent it. Acrylic absorbs moisture. Humid on one side and dry on the other, means that acrylic lids will warp.

Glass is far and above the best and safest choice for a lid.


----------



## Kalakole (Jun 30, 2011)

I really appreciate the information! I just wanted to see if there were any alternatives to glass lids but it seems they are to easy/simple to have a substitute for..


----------



## Rusty_Shackleford (Sep 2, 2010)

This is very intersting. As I have some exos I bought from a friend. He had one of his buddies put aircraft grade lexan in the top to replace the screen top. Now I have to change all that out...crap!!


----------



## parkanz2 (Sep 25, 2008)

Yep glass is the way to go. The only reason I would try to use something else is if I wanted to get UVB transmission which I would probably go for solacryl, a special acrylic product.


----------



## mitcholito (Dec 30, 2011)

Pumilo said:


> Lexan is known to leach dangerous compounds.
> 
> Plastics made from polycarbonate resin or Polyethylene Terephthalate (PET) tend to leach out a potent hormone disruptor called Bisphenol-A (BPA). BPA, a chemical found in most plastics impairs the reproductive organs and conduces adverse effects on breast tissue development, prostate development (reduces sperm count) and tumors. This chemical leaches out into the contents of the water bottle during the normal wear and tear of the bottle.
> 
> Plastic Bottles Health Hazard


You copy and paste somethng taken out of its context. If you read further in the text in the link you find that it says:



> "Exposure to heat and cleaning agents causes BPA to enter the contents of the bottle. This means leaving the plastic bottle in the car, or in the back pack and while washing the bottle with harsh detergents, can release the chemicals into the contents. In 2003, a study conducted by the University of Missouri revealed that detectable amounts of BPA leached into the liquid at room temperature. This means plastic bottles kept on the desk at room temperature can also be potentially harmful."


In normal terrariums use we dont have the kind of heat to make the plastic leak in that way, nor the harsh detergents. 
Moreover the leak of BPA is made as transfers to liquids. I cant see how the use of a Lexan piece in a terrarium would make it dangerous for the animals?

Another strange thing with this study was this:



> "20 samples of mineral water were taken, of which 9 were stored in plastic bottles, another 9 were stored in glass bottles and the remaining 2 bottles were stored in cartons. Specialized genetically engineered yeast was used to test the presence of estrogenic compounds. The test results revealed estrogenic activity in 7 of the plastic bottles and 3 of the glass bottles.


If you want you could also interpret the study as glass being a source for BPA too.

Just my two cents....


----------



## Rusty_Shackleford (Sep 2, 2010)

I have to investigate this further. I was told the lexan I have on my vivs is the same stuff they make aircraft canopies from. It's generally not available to the public.


----------



## Larguello (Mar 14, 2012)

I'm using lexan for some of my vivarium tops for about two months, haven't had any issues as of yet. However i may change it out after reading this.


----------



## Pumilo (Sep 4, 2010)

mitcholito said:


> You copy and paste somethng taken out of its context. If you read further in the text in the link you find that it says:
> 
> 
> 
> ...


You quote this line right here. _"In 2003, a study conducted by the University of Missouri revealed that detectable amounts of BPA leached into the liquid at room temperature." _

It clearly states the leaching happens at room temperature. Concerning the transfer to liquids, I see active condensation, water marks from past condensation, or wet algae/slime algae growths on every single one of my vivs. I'm not sure I've ever seen a high humidity vivarium whose top glass did not get wet at least occasionally.




mitcholito said:


> If you want you could also interpret the study as glass being a source for BPA too.
> 
> Just my two cents....


My guess here is that their test was contaminated with the glass bottles. I only pulled the first quick page I saw on lexan and BPA. Feel free to research it more. There are pages and pages about Lexan being proven to leach BPA on contact with liquid...and most vivs will have contact with liquid in the form of misting and condensation. Further, glass is has been tested as PBA free in many other tests. The very fact that they only found it in three bottles suggests contamination.


----------



## Pumilo (Sep 4, 2010)

For those who see the words "endocrine disruptor" or "hormone disruptor" and decide that since their frogs have not died yet so it must be something we don't have to worry about, consider this. Birth Control Pills are basically a controlled endocrine disruptor.
If using an uncontrolled endocrine disruptor does not concern you, then go ahead and use it. However, I was asked if anyone has any experience with it. This seems to imply a general request for information concerning Lexan. I've simply posted the concerns I have with it. Lexan, and styrofoam/polystyrene for that matter, will not be found in my vivs.


----------



## Rusty_Shackleford (Sep 2, 2010)

Thanks for posting that info Doug. I don't know if lexan is safe or not. But I'm not gonna take a chance. I bought the vivs "as is". I'm gonna replace the lexan with glass asap.


----------



## Pumilo (Sep 4, 2010)

Rusty_Shackleford said:


> Thanks for posting that info Doug. I don't know if lexan is safe or not. But I'm not gonna take a chance. I bought the vivs "as is". I'm gonna replace the lexan with glass asap.


That's exactly why I post this kind of thing Jon. Do I KNOW it's going to mess up breeding, or froglet formation? Nope. But I do know there are safer alternatives. Why take the chance if you don't have to?


----------



## Rusty_Shackleford (Sep 2, 2010)

The only thing I know about plastics, well plastic bottles is there are different grades of them. Look at the bottom of a water or soda bottle. They have different codes and symbols to tell what kind they are. I know that water bottles are meant to be used and disposed of, not refilled and used over and over again like many of us do. That's the extent of my expertise on the subject.


----------



## bsr8129 (Sep 23, 2010)

There is a hazard of going and searching the web to find information. There is no mention of the actual published papers or what concentrations were found in these tests. While there may be BPA found in leaching out from plastics it doesn't state at what concentrations nor does it say at what conc is harmful to humans or anything else. I assume most of us drank milk as babies from plastic bottles and well for me I can produce offspring. Take what you read on the Internet and from news with what you will. If I search the I can where Elvis lives where big foot lives and that aliens live among us.


----------



## jacobi (Dec 15, 2010)

Its a controversial subject, with accusations being made by many parties involved. I personally think a discussion on plastics should be backed up by scientific papers, and not news stories. Either way, whatever you do causes cancer in California 

Jake


----------



## Kalakole (Jun 30, 2011)

Thank you so much for the information, I read a bit on it and I think it's just safer to stick with the glass tops. I figure why take the possible risk when it could all be avoided? I'll just have to spring for a nice glass drill bit so i can cut my tops! (saw your glass cutting thread, was very helpful also).


----------



## Pumilo (Sep 4, 2010)

bsr8129 said:


> There is a hazard of going and searching the web to find information. There is no mention of the actual published papers or what concentrations were found in these tests. While there may be BPA found in leaching out from plastics it doesn't state at what concentrations nor does it say at what conc is harmful to humans or anything else. I assume most of us drank milk as babies from plastic bottles and well for me I can produce offspring. Take what you read on the Internet and from news with what you will. If I search the I can where Elvis lives where big foot lives and that aliens live among us.


You can do whatever you want with the information. The fact is that Lexan DOES leach BPA, and comparing it to Elvis, big foot and aliens won't change that. No, I did not bother to find stats on exactly how much is leached over how long a time period. I stated the concern and you are welcome to look for whatever papers and studies you care to. It wouldn't matter anyway. If you are waiting for science or big business to spend big money to test the effects of varying amounts of BPA on dart frogs, you're going to be waiting a very long time. Studies on amounts that will affect humans are simply not the same. There is, well, a small size and weight difference for starters.
I am simply stating a concern. Lexan does leach BPA. There are safer choices, not to mention a choice that is a fraction of the cost.
It all boils down to this. Lexan MAY present problems. Glass has proven to be a viable, safe alternative. Do whatever you want with it.


----------



## jacobi (Dec 15, 2010)

Yeah, its a simple equation. Possibly hazardous vs proven safe.

Jake


----------



## Pumilo (Sep 4, 2010)

I really didn't think it necessary, as it is pretty widely known that polycarbonate does leach PBA but here are a few from google scholar backing this.

Polycarbonate Bottle Use and Urinary Bisphenol A Concentrations
K-State Research Exchange: Environmental assessment for bisphenol-a and polycarbonate
http://cosmos.ucdavis.edu/archives/2010/cluster8/WON_Jason.pdf


----------



## bsr8129 (Sep 23, 2010)

I don't argue that BPA leaches from plastics or that it's an Endocrine distributor but at what levels. And at what levels does it leach out over what period of time. It's a pet peive of mine to see stuff thrown out there with no real understanding. We can all do whatever we want with the information. But there is a difference between saying the sky is falling and it actually falling. 

It even seems BPA is in the air we breath 

Something's in the air: BPA found around the world. — Environmental Health News


----------



## Pumilo (Sep 4, 2010)

bsr8129 said:


> I don't argue that BPA leaches from plastics or that it's an Endocrine distributor but at what levels. And at what levels does it leach out over what period of time. It's a pet peive of mine to see stuff thrown out there with no real understanding. We can all do whatever we want with the information. But there is a difference between saying the sky is falling and it actually falling.
> 
> It even seems BPA is in the air we breath
> 
> Something's in the air: BPA found around the world. — Environmental Health News


So the fact that it is in the air we breathe, because of plastic manufacturing processes and burning plastic waste, means that we should ignore the potential hazards and not bother to try to limit exposure?


----------



## mitcholito (Dec 30, 2011)

> So the fact that it is in the air we breathe, because of plastic manufacturing processes and burning plastic waste, means that we should ignore the potential hazards and not bother to try to limit exposure?


What I meant was that you can always choose to interpret studies and "facts" in different ways. And especially what you find on the internet!

No fault in choosing glass instead of plastic. Glass have many benefits. But sometimes it has its limitations and a piece of Lexan will do the job. 
These studies were made a decade ago and we still drink from PET bottles.
I can see many other things in our homes that is more harmful to the animals.


----------



## parkanz2 (Sep 25, 2008)

mitcholito said:


> What I meant was that you can always choose to interpret studies and "facts" in different ways. And especially what you find on the internet!
> 
> No fault in choosing glass instead of plastic. Glass have many benefits. But sometimes it has its limitations and a piece of Lexan will do the job.
> These studies were made a decade ago and we still drink from PET bottles.
> I can see many other things in our homes that is more harmful to the animals.


Just a few points to add to the discussion.

Polyethylene terephthalate (PET) hasn't been implicated in any BPA releasing scenarios. The biggest concern is polycarbonate which is what Lexan is. It's a type 7 plastic which is a miscellaneous "catch all" group which is listed as a risk for BPA exposure. And as Doug has shown, polycarb specifically is shown to release BPA. I don't think anyone uses polycarb for drinking bottles anymore but I could be wrong. I avoid bottled drinks in general.

I can sympathize with the arguments concerning the levels BPA leached and whether it's a concern or not. "The dose makes the poison" as Paracelsus said. This idea is drilled into my head by multiple professors as I go through coursework concerning medications, therapies, etc. My concern is that we just don't know how much this will affect the frogs. As Doug said, no one is going to fund a research project on the effects of BPA on different amphibian species so we're stuck using assumptions based on findings in other species and anecdotal evidence.

There's a known risk. How much it can affect frogs is unclear. I won't be using it. It's very simple in my mind, but based on the lack of evidence it's very much a personal choice.


----------



## WingedWolfPsion (Mar 8, 2010)

When it comes to something as delicate as a frog, the more you can keep endocrine and hormone disrupters out of their environment, the better.

Someone asked at what level these substances affect living things. The answer is, we still aren't sure, but what we do know is that it takes VERY VERY LITTLE. Tiny trace amounts of these substances have noticeable affects, which is why the prevalence of this stuff in our environment is an issue, and it IS affecting US, as a species. 

BPA Exposure in Womb Linked to Behavioral Woes in Girls - Yahoo! News

It's also been tied to an increased risk of hypospadias in boys. It's bad stuff, it's everywhere. Frogs are likely to be far more sensitive.


----------



## NickJR (Jul 28, 2011)

ive used a lexan top for over a year with no problems

Sent from my SPH-D710 using Tapatalk


----------



## parkanz2 (Sep 25, 2008)

NickJR said:


> ive used a lexan top for over a year with no problems
> 
> Sent from my SPH-D710 using Tapatalk


Keep in mind that not all problems are observable.


----------



## Mantellaprince20 (Aug 25, 2004)

Just my 2 cents, but if you use plastic deli cups as froglet containers, tupperware sa froglet containers, or plastic deli cups as fruit fly cultures, you are bound to subject your frogs to far higher BPA levels than by using a lexan top. 

Most of the studies that I have seen on the BPA product are slightly botched. Contamination of the samples is very common, as any plastic lab item that is used, syringes, pipet tips, etc, all contain BPA, and this is typically not accounted for. Furthermore, any tests they have ran where they subject an animal (such as a mouse) have used a VERY high concentration of BPA to show any actual effects (much higher concetration than those found leaching in bottles).


----------



## goof901 (Jan 9, 2012)

but deli cups are plastic #5 which are supposed to be safe. i feel like glass is a better alternative because even tho deli cups are "supposed" to be safe, there is always that chance that there is an unknown toxin. i agree with doug, there is no need to increase the concentration of BPA in you viv. go with glass, a proven safe material


----------



## jacobi (Dec 15, 2010)

My two cents... Without going into the science side, and bear in mind that some of the studies may be questionable since they are not independent, and the FDA is a government body (enough said!)...

If there is the possibility of risk, and safe alternatives are available, what are the benefits of going with the material that poses the possible risk? 

Jake


----------



## Kalakole (Jun 30, 2011)

All are valid points and lexan seems to only be a potential risk but, to everyone their own. If you think its safe use it, if you don't wanna risk it don't.. just what I get out of all of this


----------

