Waterproof Mattress Cover with Polyurethane Backing

August 24, 2014, by Debra Lynn Dadd

Question from TA

I am looking for a waterproof mattress protector to take along while traveling, to protect the bed from any leaks my toddler might have. It seems like the best options I've found so far are the "waterproof breathable" mattress covers, which are cotton terry with a polyurethane membrane:

MALOUF SLEEP TITE Hypoallergenic 100% Waterproof Mattress Protector - 15-Year U.S. Warranty - Vinyl Free - Queen

Queen Size Luna Premium Hypoallergenic 100% Waterproof Mattress Protector - Made in the USA - Vinyl Free

SafeRest Queen Size Premium Hypoallergenic Waterproof Mattress Protector - Vinyl Free

The prices seem reasonable, and the SafeRest and Luna ones have over 3,000 reviews each, most of which are positive. I see a number of good things: made in the USA, free of PVC, not thick or crinkly, protects against dust mites and allergens, etc. But what I'd like to know is whether you think this polyurethane membrane is non-toxic and free of chemical smells. It appears to fold up like a sheet and would be easy to take when traveling (well, easier than a bulkier mattress pad, anyway!). I need to get something right away, but I'm holding back until I get more assurance about this PU membrane. It definitely seems better than PVC. What do you make of it?

The disposable options don't seem like a great idea, and other smaller options tend to have plastics and PVC. Wool is pricey and thicker/heavier to haul along with all our other travel gear. Vinyl is a definite "no." A folded-up towel isn't super effective and smaller things like that also shift around while sleeping on them. So I keep coming back to a mattress cover like these I linked to above, but I'd just like to feel sure that they are free of toxicity.

Ughhh... Now that I looked more closely at the Q&A on the product pages for the Luna and the SafeRest covers, I see that customers asked what materials are used in the covers, and the answer is 80% cotton and 20% polyester. I had assumed that the cotton terry was 100% cotton. It appears that this one might be 100% cotton surface:
www.amazon.com/LinenSpa-Waterproof-Mattress-Protector-Eliminates-Warranty/dp/B00A2WEJY4

In all cases, I see reviews that say "my toddler (or dog) had an accident or diaper leak or spill on the bed and nothing got through to the mattress" and those that say "my toddler (or dog) had an accident/leak/spill on the bed and the mattress got soaked." I don't know why there would be such variability in user experiences. The reviews overall seem positive. There are also differing report about whether the covers make the users feel hot and sweaty. Along the same lines, I came across the Gotcha Covered mattress cover that uses organic cotton and a recycled PU backing; but the price is considerably higher (more than 3 times higher than some of the others), and out of 4 reviews, 2 of them are negative, saying "hot and sweaty" and "not waterproof." Since it's something I need just for travel, I'm not inclined to pay that much more for something that might not work very well.

I also see this Natural Mat product, which is not as large of a cover; it is designed for a crib mattress, but I believe it would lie flat on the bed. They also use PU, but it is apparently contained between the 2 layers of organic cotton.

I am aware that Naturepedic makes a safe cover, and I've actually had one. However, it is more expensive, fairly heavy, and it did not protect the new mattress it was used on from body oil. It wasn't tested against urine, so I can't speak to its effectiveness for that purpose.

Debra's Answer

All of the mattress protectors you are describing are using the latest technology of a very thin layer of polyurethane fused to a fabric, so it can be waterproof without the sweatiness or noise of a vinyl mattress cover.

The difference between the different brands is the type of fabric used.

Because I'm familiar with the one sold by Naturepedic, I can tell you that the polyurethane film is completely nontoxic. I've seen and smelled samples of this film and there is no odor whatsoever.

And I've researched polyurethane. Polyurethane itself, as I've said many times before, is completely nontoxic. What makes polyurethane foam and polyurethane wood finish toxic is the additives. But this film is simply polyurethane. Though made from petroleum, it is nonetheless not toxic.

Naturepedic is so scrupulous about not using toxic materials that if Naturepedic uses a material, it can be trusted to be safe. In addition, they have their products tested by independent third parties that verify they meet nontoxic standards.

About their polyurethane film, Naturepedic says, "Drysleep uses a specially formulated polyurethane waterproof barrier that is proven to not leach harmful chemicals. It is made from the same grade material as is required for food contact applications. It also meets the highest standards for medical device biocompatibility (USP Class VI). It does not contain any fire retardants or antimicrobial treatments and is free of vinyl/PVC, phthalates and latex. It also easily passes the GREENGUARD “Gold" certification standards for chemical emissions. With a Naturepedic organic mattress pad, you never have to worry about harmful chemicals or allergenic materials."

So this gives you something to compare to with the other brands.

As to whether or not this polyurethane film protects from urine or other liquids, I don't know why it appeared to not work for some, but as you said, the majority of the reviews are positive. I see no reason not to use one of these mattress protectors.

Toxic-Free Q&A

These are archives of Q&A asked by readers and answered by Debra Lynn Dadd (from 2005-2019) or Lisa Powers (from 2019-2020). Answers have been edited and updated as of December, 2020.