Polyurethane Foam - which type offgasses least?
Dec 5, 2011 10:33 PM
Joined: Dec 5, 2011
Points: 7
Hi,

 

Because of chemical-sensitivity issues, I am not all that thrilled at all about buying a mattress with polyurethane foam, or purchasing a foam component to build my "sleep system" - but for ergonomic reasons, I may have no choice (yes, I've tried the supposedly "healthier" latex - it didn't work out).  So I wanted to ask this forum - what properties should I look for in foam that would minimize my exposure to offgassing substances and toxic flame retardants?

Is it true that the softer (in ILD) the foam is, the more it offgasses - or is the opposite true?  What about densitity - how does increasing densitiy affect the amount of offgassing?  Are there certain types/brands of foam that are known to offgass less than others?  Does the amount of flame-retardant used in the foam vary with firmness-level and/or densitiy? 

While I'm at it - I might as well ask if anyone knows of any particular brand of mattress that has little-to-no offgassing?  Which would be the lesser of the evils as far as this is concerned?  (My budget is quite limited - I cannot spend more than $800 on this mattress.)

Thanks for any feedback...

Re: Polyurethane Foam - which type offgasses least?
Reply #4 Dec 12, 2011 2:43 PM
Joined: Dec 17, 2009
Points: 850
That is quite the pickle.  Natural rubber does indeed have an odour; and all polymer materials break down over time including polyurethane...  Technically...even steel outgases...just slower than polymers do.  What matters is the toxicity...natural rubber is harmless...but of course if you are really sensitive to smells than even odour (even if it is harmless) might cause you issues.  You may want to consider a coil mattress with nothing but cotton in it.  Vivetique seems to be one of the more reasonably priced...there is another...but my mind is drawing a blank right now.  
Re: Polyurethane Foam - which type offgasses least?
Reply #5 Dec 14, 2011 8:33 AM
Joined: Dec 5, 2011
Points: 7
budgy wrote:

 

 

That is quite the pickle.  Natural rubber does indeed have an odour; and all polymer materials break down over time including polyurethane...  Technically...even steel outgases...just slower than polymers do.  What matters is the toxicity...natural rubber is harmless...but of course if you are really sensitive to smells than even odour (even if it is harmless) might cause you issues.  You may want to consider a coil mattress with nothing but cotton in it.  Vivetique seems to be one of the more reasonably priced...there is another...but my mind is drawing a blank right now.  

I'm a little confused about polyurethane foam:  on the one hand, they say that it's not biodegradable and will persist in the environment idefinitely.  On the other hand, foam is known to soften over time - which seems to be indicative of some kind of long-term "breaking down" process.  Does foam eventually break down to the point of no longer being a solid unit - ala latex?  Does the process of "softening" release volatile substances (or put another way:  does the act of softening involve offgassing of any sort)?

While I have come to the conclusion that all types of latex seem to be potentially bothersome - I do wonder if I had made the decision to buy a mattress consisting of 100% natual Dunlop latex - instead of the partially-synthetic Talalay latex mattress that I did buy - would that mattress have been more tolerable.  While I do have some experience with 100% natural latex samples that reveals that it also has a persistent odor and might be bothersome - my observations of 100% natual latex might be slightly clouded by my horrible experience with the synthetic Talalay.  I'm less willing to go through the whole process of trying out and possibly returning another latex mattress (a process that also drains funds).  I've already wasted enough money.  

The odors of both types of latex were so permeable that my clothes often seemed to reek of the odor - that is no way to spend one-third of your life.  

And I believe I've read that even 100% natural latex is an aromatic hydrocarbon - a substance that can give people with chemical sensitivities quite a bit of trouble.  Also, there might be certain additives and/or flame retardants within the latex that are bothersome.

I wish I had been better informed so I could have avoided the decision to buy the synthetic Talalay mattress - but information regarding the constituents and the properties of these mattresses is hard to come by, to say the very least.  There is a lot of seductive material on the web about latex mattresses that hypes all kinds of alleged positive qualites (i.e. it's supposed low-toxicity, it's antimicrobial qualities) - information revealing the downsides of latex is scant at best.  It was only after I bought the mattress and was experiencing problems with it that I did some digging and learned that styrene - a component of the styrene-butadiene rubber used in synthetic latex - is a probable human carcinogen.  

I am fairly health-conscious, which makes me feel all the more foolish for failing to forsee that there would be those problems with synthetic (and possibly natural) latex.  I was hoodwinked by the propaganda.  It's not like these companies are forthcoming with the fact that their product smells like gasoline, or continuously offgasses volatile substances that have gasoline-like odors - although they should be.

 

 

 

P.S. - just wanted to add that it is the synthetic latex that smells like gasoline - not necessarily the 100% natural latex.  From my limited experience with 100% natural latex, it has more of a pure-rubber smell, which would give one the idea that it is less toxic (whether that is actually true or not).  I don't want to condemn all types of latex as having that odor - although as I said above, even the 100% natural latex could potentially be problematic.
 

This message was modified Dec 14, 2011 by fumesallnight
Re: Polyurethane Foam - which type offgasses least?
Reply #6 Dec 14, 2011 8:46 AM
Joined: Dec 5, 2011
Points: 7
budgy wrote:

 

That is quite the pickle.  Natural rubber does indeed have an odour; and all polymer materials break down over time including polyurethane...  Technically...even steel outgases...just slower than polymers do.  What matters is the toxicity...natural rubber is harmless...but of course if you are really sensitive to smells than even odour (even if it is harmless) might cause you issues.  You may want to consider a coil mattress with nothing but cotton in it.  Vivetique seems to be one of the more reasonably priced...there is another...but my mind is drawing a blank right now.  


Sorry - my posts are so long that I feel the need to make multiple posts out of them - but I was on the Vivetique website and from what I saw, there were no published prices on their products.  That is often a bad sign that the prices are sky high.

The only "mass market" mattress that I've seen that appears like it might contain no foam is a Sealy mattress sold on the Sears website.  I first came across it several weeks ago - then, when I returned to the website, I was disheartened to see that the price of this mattress seemed to spike to twice as much as it was when I first viewed the page.  (I hate these pricing games.)  Based on the overall market - paying over $500 for a basic, "bare bones" mattress that contains no foam layers seems excessive (and that $500 is for the mattress alone - the foundation is an additional $200 - $300).

Considering that you can pay less for "plusher", more layered mattresses - is this worth $522?

http://www.sears.com/shc/s/p_10153_12605_08212678000P?blockNo=51&blockType=G51&prdNo=1&i_cntr=1323845968552

 



 

This message was modified Dec 14, 2011 by fumesallnight
Re: Polyurethane Foam - which type offgasses least?
Reply #8 Dec 14, 2011 3:08 PM
Joined: Dec 17, 2009
Points: 850
Talking about various types of breakdown and decay of polyurethane foam versus synthetic latex (SBR) and natural latex (NR).  Things are a little different. 

It is true that in a landfill we have no idea how long polyfoam will stay around for, it does not readily bio-degrade.  So this process could take hundreds or even thousands of years. SBR is somewhat similar as well, it does not readily biodegrade, although because it is not plastics based it might break down a little quicker.  Natural rubber would break down pretty quickly in comparison.  

WIth regards to breakdown from functional use in a mattress, natural rubber or even synthetic latex lasts a lot longer than polyurethane based foams.  Polyurethane  softens a lot from use, this is loosely related at best to the chemical off-gassing component, and has more to do with the cell structure of the foam simply being more brittle and less elastic than natural rubber.  

With regards to the various types of odours and what really causes them.  With polyurethane foams a lot of people assume that chemical off-gasing is somehow a temporary thing; this is because the odours are always much stronger when the mattress is brand new and will dissipate with time. In truth the off-gasing is indefinite, the product does break down over time, as all polymers do. Most of the chemicals released over time are odourless, or are odourless below a certain concentration.  For instance formaldehyde below something like 20 ppm (parts per million) is usually undetectable.  Above that, it can have a pretty powerful odour to some people.  

Synthetic latex does have a distinctive chemical type smell to it, I would say less so than polyurethane foam...I do not mean to be argumentative because obviously what you experienced was very real to you...but I would not describe it like gasoline.  Gasoline is an incredibly powerful and offensive smell...realistically if the beds smelled like that no one would buy them after laying on them...in any event some people are much more sensitive then others when it comes to these things. 

Natural rubber has a smell that by definition will never go away because its not some kind of chemical additive that causes it...its the natural smell of hevea milk.  It may be very noticeable to some individuals, and not so much to others. But for instance if you walked into a room full of apples....you could smell the apples.  

The reason I suggest cotton filled mattress...is that cotton is relatively odourless as well as non-toxic...its one of the only materials in the world I could list that fits both of those criteria. 

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