Flexible tubing

[ckyuv]

Kinda like that post that Dan made about the plastic bags

http://www.reef2rainforest.com/2015/07/15/coral-excerpt-reefkeeping-101-all-about-plasticizers/

[jestep]

What bothers me is that a conclusion and recommendation to stop using vinyl tubing is formed without any specific study of the effects on marine life. Not saying it's not possible, but there's probably a few million reef tanks in the US alone using vinyl tubing and I would think there would be significant examples of negative effects of PVC plasticizers just based on real life usage. As far as I can tell, there's zero articles or any attributable level of morbidity associated with using vinyl tubing in reef tanks.

With that being said the actual cost of silicon is actually cheaper than vinyl when you consider how much longer it lasts. It does require about twice the upfront cost though.

[flexpvc]

Hello,

This is Eric at Flexpvc.com.

Seems this subject comes up every few years. So to help quell the confusion here is the data.

All of our PVC products (sold at Flexpvc.com) contain a plasticizer called Di-isononyl Phthalate (or DINP).

Several years ago, there was a great deal of scrutiny on a plasticizer called Di-octyl Phthalate (or DOP). DOP was one of the most commonly-used plasticizers for decades, but was linked in some studies to various health risks...If I remember correctly, some lab rats exposed to high levels of DOP as juveniles exhibited stunted organ growth, obesity and heart problems as adults.

This led to a lot of bad publicity that resulted in DOP (Sometimes also called DEHP) being banned in many parts of Europe and the USA. It also made the word "Phthalate" a popular "danger word" amongst many consumer groups.

IMPORTANT NOTE: There are many places on the net selling flexible pvc pipe (referring to it illegally as "flex pvc" our registered trademark) made in MEXICO, China and other none US, non-UK locations. Since DOP has not been banned from those locations and since it's cheaper to use then the other plasticizers, you can bet it's probably being used. That is why we have the page "Why is it important to buy Made In The USA Flexible PVC Pipe from Flexpvc.com" (see http://flexpvc.com/MadeInTheUSAFlexPVCPipe.shtml)

Many people don't realize that "phthalate" actually refers to a whole family of chemical compounds. There are many that are demanding that ALL phthalates be banned. For what it's worth, our plasticizer (DINP) is considered one of the most benign, and is commonly used in food-handling and baby products.

As for "off gassing" or "leaching" that too became a popular concern in the media a few years back and is basically just a fancy term for "evaporation." As you know, the plasticizers will eventually evaporate of the PVC leaving it stiff and brittle. Many people don't seem to realize that this is why you get that cloudy film on the inside of your car's windshield.....that is from the plasticizers evaporating from the vinyl dashboards, trim and seals in your car. But where does it "evaporate" to? Not the water. That's a higher pressure zone. Evaporation always goes in the direction from higher pressure to lower presure. So they come out into the air. I suppose if the plasticizer we used was the dangerous one and if you stuck your head under the tank and breathed it for months on end.... it might have a health risk. But we don't use COP or DEHP and you don't live under your tank, and the fish don't "breath" is because it goes from the hose/pipe to the atmosphere not the water. :-)

In short, unless someone is eating PVC by the pound, the actual exposure to anything "dangerous" from our PVC products would be about the same as an average person experiences handling plastic products through the course of the day (holding a phone, typing on a keyboard, eating with plastic utensils, drinking through a plastic straw, etc.)

As always all we can do is offer the best information available and let the customer decide. :-)

As for the article on silicone tubing.... silcone is a fine product. But I do question the hit piece on pvc without the data. ;-)

[Makena95GT]

^this is the type of business I love. One that can explain in detail what's going on and still have it make sense to someone like me who can get confused by words easily lol

You sir, are awesome

Sent from my LGLS660 using Tapatalk

[flexpvc]

Also, and this is very important, for anyone that bought Non-USA flexible pvc pipe in the past and wants to replace it, we are offering free shipping on replacement rolls. You have to provide your hard copy of your receipt from the location you bought it from that sold you non-us made flexible pvc pipe, and we'll help you get that stuff out of your system.

Thanks

[flexpvc]

^this is the type of business I love. One that can explain in detail what's going on and still have it make sense to someone like me who can get confused by words easily lol

You sir, are awesome

Sent from my LGLS660 using Tapatalk

I'm humbled. Thank you sincerely. :-)

[jestep]

I'm humbled. Thank you sincerely. :-)

Is there any major chemical difference (rigidity aside) between the clear flexible vinyl tubing and the flexible PVC that you guys offer? Article is sort of vague on whether they are referring to the stuff you guys offer or the other tubing or both.

I have always used the flexible vinyl for my pump returns and have used the flexible PVC several times on other projects. Throwing out any obvious cognitive dissonance, I like to see something other than anecdote when an affirmative claim is made for or against a product, which that article is clearly doing.

[ckyuv]

I have always just gone to Home Depot and got whatever tubing fit in the barb I had and didn't pay attention to where it came from or what it was made of. Thanks for the info flexpvc

[flexpvc]

I'm humbled. Thank you sincerely. :-)

Is there any major chemical difference (rigidity aside) between the clear flexible vinyl tubing and the flexible PVC that you guys offer? Article is sort of vague on whether they are referring to the stuff you guys offer or the other tubing or both.

I have always used the flexible vinyl for my pump returns and have used the flexible PVC several times on other projects. Throwing out any obvious cognitive dissonance, I like to see something other than anecdote when an affirmative claim is made for or against a product, which that article is clearly doing.

Question 1,

Almost any tubing or hose other than Silicone or Rubber will have some plasticizer in it. Both the clear vinyl tubing (which is really PVC, you can even glue it with standard PVC Glue/Cement/Primer) and our flexible pvc pipe have the same plasticizer in it. I believe they used the term "vinyl" not to confuse people when the products first started to be sold and the name has stuck. But they are mostly the same materials, just manufactured in a different way.

Question 2.

I gave the names of the plasticizers. The one we use and the one banned and shown to be maybe harmful. It'll take a minute on google to look them up. I know for a fact some, maybe much, of the flexible pvc pipe sold online NOT from our site is imported. If you want to check yourself, just ask them for a certificate of origin. If you exporting the product by NAFTA they have to provide a COA. It's a legal document. It must show where the product is made. As for the plasticizer you'd have to ask. They may or may not be truthful.

Did I misunderstand your 2nd Question? If so please let me know and I'll try again. :-)

Thank you.

[flexpvc]

I have always just gone to Home Depot and got whatever tubing fit in the barb I had and didn't pay attention to where it came from or what it was made of. Thanks for the info flexpvc

And years ago you could have done that. But the last several years we've seen a flood of imported products. As one of the original sites (if not the first site) selling flexible pvc pipe online, we get tons of offers to sell to us... all from imported distributors. So we know what is out there. :-)

What has prompted me to write this is the no. of customers who have come to us with defective product (bought from other sites) over the last 2 years. 2011 was the big year for the imported stuff and it seems to break down in about 2-3 years. So I expect much more in the coming years. ;-/

Please don't blame me, I'm just the messenger. ;-)

[victoly]

As for "off gassing" or "leaching" that too became a popular concern in the media a few years back and is basically just a fancy term for "evaporation." As you know, the plasticizers will eventually evaporate of the PVC leaving it stiff and brittle. Many people don't seem to realize that this is why you get that cloudy film on the inside of your car's windshield.....that is from the plasticizers evaporating from the vinyl dashboards, trim and seals in your car. But where does it "evaporate" to? Not the water. That's a higher pressure zone. Evaporation always goes in the direction from higher pressure to lower presure. So they come out into the air. I suppose if the plasticizer we used was the dangerous one and if you stuck your head under the tank and breathed it for months on end.... it might have a health risk. But we don't use COP or DEHP and you don't live under your tank, and the fish don't "breath" is because it goes from the hose/pipe to the atmosphere not the water. :-)

Overall, I agree. This is probably NOT a big deal. However, I don't know that I 100% agree with you on the "plasticizers go straight to air" statement. Pthalates belong to a class of chemicals called Semivolatile Organic Compounds, which as a general rule, are only marginally likely (semi, lol) to be apt to directly sublimate from a solid, through the aqueous/dissolved phase and out into the atmosphere. I see pthalates in groundwater regularly.

Even though I technically disagree with the statement that they jump right out into the air, I agree that the likelihood of issues are small, and that most people run GAC which would remove it from the water column anyway.

[flexpvc]

Overall, I agree. This is probably NOT a big deal. However, I don't know that I 100% agree with you on the "plasticizers go straight to air" statement. Pthalates belong to a class of chemicals called Semivolatile Organic Compounds, which as a general rule, are only marginally likely (semi, lol) to be apt to directly sublimate from a solid, through the aqueous/dissolved phase and out into the atmosphere. I see pthalates in groundwater regularly.

Even though I technically disagree with the statement that they jump right out into the air, I agree that the likelihood of issues are small, and that most people run GAC which would remove it from the water column anyway.

Hello Sir,

Thanks for the reply. When I was saying they go to the air, what I mean by that is you have a hose. On the inside is a liquid under pressure above 1 ATM (water). On the outside of the hose you have air at 1 atmosphere. I realize it's a tiny difference, but it is a difference non-the-less. Also the ID of the hose is much smaller than the OD of the hose, therefore the surface area on the OD is greater than the surface area of the inside of the hose in contact with the liquid. So it's my contention that these two factors would cause the pthalates to "migrate" toward the OD of the hose, not the ID.

I have no doubt you have found them in ground and every other kind of water. No disagreement there. :-)

[jestep]

Not to derail even further, but wouldn't natural biofilm that occurs in submerged parts reduce the efficiency of transfer as well?

I know this phenomenon occurs in galvanized systems such as stock tanks and galvanized piping. After a certain period of time, the barrier basically prevents any zinc all at from going into solution.

[victoly]

Overall, I agree. This is probably NOT a big deal. However, I don't know that I 100% agree with you on the "plasticizers go straight to air" statement. Pthalates belong to a class of chemicals called Semivolatile Organic Compounds, which as a general rule, are only marginally likely (semi, lol) to be apt to directly sublimate from a solid, through the aqueous/dissolved phase and out into the atmosphere. I see pthalates in groundwater regularly.

Even though I technically disagree with the statement that they jump right out into the air, I agree that the likelihood of issues are small, and that most people run GAC which would remove it from the water column anyway.

Hello Sir,

Thanks for the reply. When I was saying they go to the air, what I mean by that is you have a hose. On the inside is a liquid under pressure above 1 ATM (water). On the outside of the hose you have air at 1 atmosphere. I realize it's a tiny difference, but it is a difference non-the-less. Also the ID of the hose is much smaller than the OD of the hose, therefore the surface area on the OD is greater than the surface area of the inside of the hose in contact with the liquid. So it's my contention that these two factors would cause the pthalates to "migrate" toward the OD of the hose, not the ID.

I have no doubt you have found them in ground and every other kind of water. No disagreement there. :-)

I see where you're going now. I think it's probably a pretty complex model in reality, as jestep pointed out above. While the pressure in the ID of the tubing is higher than atmospheric, I would imagine that flowing salt water is much more likely to dissolve a constituent than just ambient air. It also kind of depends on how various internal chemicals in the tubing migrate as the exterior (or interior) surfaces react to layers being stripped away. (Props to jamie again) Also you have the biotic factor on the interior of the tubing. All things said, it's probably a pretty complex model.

Give me a few months and I'll set something up in the lab

[flexpvc]

Give me a few months and I'll set something up in the lab

Yea, that's about the only way to settle this. :-)

In the end, probably "much ado about nothing."

[ckyuv]

My mind is blown. Thanks guys.