Green Diapers: SAP, biodegradability, chlorine, woodpulp

gdiaper.jpg sevgen_diaper.jpg

  • Introduction

The choice of a “green” or “ecological” diaper is not straightforward. In my previous review of Seventh Generation diapers, Whole Foods Private Label 365 diapers and gDiapers, I tackled the following issues:

  1. Comfort, leaks and diaper rash
  2. Chlorine
  3. Plastic, latex, TBT, polyurethane/polypropolene
  4. Biodegradability (vs. flushability)
  5. gDiaper hands-on aspects
  6. Price
  7. SAP or Sodium polyacrylate

After receiving suggestions from readers and replies to queries from the companies, I decided to revisit some of these issues. Below you can find more detailed information about these diapers, and an investigation of some of the claims that are made on their behalf:

  1. by the companies: “this diaper is chlorine-free and that is how we differ from other disposables.”
  2. by the consumers: “it’s green so if I throw it in the trash, or flush it down the toilet, it will biodegrade in the landfill or sewage.”

It is easy to take these claims at face value, but a conscientious consumer will question and weigh them against one another: is one green diaper better than another? Are green diapers better than non-green disposables? are disposables better than cloth diapers?

{Correction} in my previous review I mistakenly wrote that Seventh Generation claims that their diapers are plastic-free. This is not the case, that is, they do not claim this, and their diapers do contains plastics (“poly,” see later). Mea culpa! I’ve removed the faulty claim from the review

  • SAP (super absorbent polymer, a.k.a., sodium polyacrylate)

In the old review my two main concerns – the ones that separate the cloth from the disposable from the flushable people – are SAP and biodegradability. These two turn out to be intricately related.

If you have a problem with SAP, it is probably a health-related concern (see previous review). If you can’t stand them, then cloth is your choice, because all the diapers I reviewed use them.

Seventh Generation, gDiapers, as well as the Whole Foods 365 brand have SAP. As do TenderCareDiapers, rumored not to use SAP. Cf. Jolene at TenderCareDiapers (email 24 May 2007):

The superabsorbent in TenderCareDiapers Plus is the same as in Huggies, Seventh Generation, Luvs, etc. Our supplier has informed us that the super absorbent polymer in TenderCareDiapers Plus contains a partially neutralized cross lined sodium polyacrylate that has been found to be safe for use in diapers through extensive testing internally as well as by external sources.

In a fantastic Grist interview (from which I will quote more), Jason and Kimberley Graham-Nye, the inventors and founders of gDiapers, address the issue of SAP (bolds mine):

Sodium polyacrylate has been rigorously tested both in the U.S. and abroad, and the predominant conclusions are that it is completely safe and non-toxic. MBDC is a leading U.S.-based design chemistry firm that has assessed SAP as GREEN, which is the safest assessment a chemical or material can receive. The FDA has approved SAP as a food additive, and the EPA considers SAP “harmless” when ingested. A 10 pound baby would have to eat about 200 grams of SAP — or 50 gDiapers! — to be at risk. Also, to put this in perspective, SAP is less toxic than table sugar. We appreciate that no matter what arguments we put forth there will be parents who are still not comfortable with SAP in their diapers. Fair enough. For us, the plastic in disposables is a much bigger issue for both our sons’ health and comfort.

A food-additive: there’s food for thought! Here is, by the way, another application of those SAPs: we’re even sticking it into farmland and using it to raise whole countries.

In my previous review I wondered why Seventh Generation uses SAP in their diapers, but make such a big deal about not using it in their feminine care Maxi Pads. Here is their response to this question (email from Louis Chapdelaine, May 24, 2007):

The natural super absorbent material that we use in the design of our feminine hygiene products lend themselves well for that particular application but not so much for diaper design applications. That has to do with the material capacity to absorb but also with the characteristics of the fluid that needs to be contained. The good news is that new generations of super absorbent polymers technologies are emerging. I believe these materials are promising in terms of opening the door to using more sustainable absorbent polymers in the design of baby diapers. As you would presume, sustainability is a very important part of the design equation at Seventh Generation.

But SAP is also at the center of the biodegradability-issue, about which next.

  • Biodegradability in landfills

Diaper buyers believe that by using “ecological” diapers, we contribute less to waste. Yes, we dump them in the trash and they end up in the landfill, but there they will miraculously biodegrade, no? No. That they are “biodegradable” or “designed to biodegrade” doesn’t mean that they actually do. It turns out that even the organic, truly biodegradable stuff in them does not degrade in a landfill.

In fact, each of the diaper companies I wrote to admit to this (you have to do some asking and digging to get to that fact, though).

In response to my query about this, Jason Hays, Guest Services Content Administrator of the WF 365 Private Label, emailed me the following (on 24 May 2007, bolds mine):

Although wood pulp is a 100% biodegradable material, there have been 100 year old newspapers (made of wood pulp) found intact in landfills. US landfills are anaerobic (no air) and [have] no water or light facilities – all key elements necessary for biodegradability.  We know of no commercial composting facilities for disposable diapers and temperature could never be high enough to decompose a disposable diaper.  We do not advocate home composting disposable diapers because of possible feces contamination of ground water. We understand Australia is having some good results using tiger worms decomposing our diapers.

Also Seventh Generation volunteers this information on their website (in the FAQ, my bolds):

Just like most disposable diaper designs in the marketplace, Seventh Generation diapers are not readily biodegradable, nor can they be composted. Many of the materials used are synthetic, and do not readily biodegrade. The inner pulp of the diaper is made of 100% total chlorine-free whitened wood pulp fibers. This pulp is mixed with a super absorbent polymer (SAP) that does not biodegrade. Most diapers end up in a landfill where they will not biodegrade, even if they were designed to do so.

And to clarify even further, Louis Chapdelaine, of Seventh Generation, emailed me the following (25 May 2007, bolds mine):

I am not aware of any disposable diaper designs out there that could claim 100% biodegradability. 80% is about the max that I have seen in a design and this is by far a leading design. Everybody else is quite a bit behind that. That design can be found in the European market where access to biopolymers tends to be easier. Now, that does not mean that because a material going into a diaper design is said to be biodegradable that it will in fact readily biodegrade. That depends on the conditions and the conditions do not lend themselves well for biodegradability in a landfill which is where the vast majority of disposable baby diapers end up at. This is why caution must be exercised when evaluating the sustainability aspect of a baby diaper design; biodegradability alone can be somewhat misleading.

  • Poly’s?

Seventh Generation lists “poly” among the ingredients of their diapers. I assumed it was polyurethane, and left it at that, but in a comment, Annika suggests: “It is still plastic; in fact, it’s the same polypropolene used to line landfills (that’s how water-tight and air-tight they are!).”

I’ve written to Seventh Generation for clarification and am waiting for a reply, and indeed, it is polypropolene (L. Chapdelaine), which is used to enclose landfills.

Also the Whole Foods 365 diapers contain polypropolene, more specifically:

The diaper covers contain polymerized propylene spun bound non-woven material.  The absorbency gel is a non-toxic Super absorbent Polymer consisting of partial sodium salt of cross linked polypropenoic acid.  [Jason Hays, email of 31 May 2007]

There is an interesting thread about how poly’s – polyurethane (PE), polypropylene (PP) – behave in landfills here.

  • Biodegradability of gDiapers: SAP again

At this point gDiapers comes in with two promises.

  1. the disposable part of their diapers is fully biodegradable (with the exception of the SAP). There are no “poly”’s to worry about.  “The outer material of the flushable refill is viscose rayon, a natural material that comes from trees. It is the only polymer used in the textile industry that comes from a natural, renewable, and non-fossil-fuel source.”
  2. this biodegradable material won’t end up in the landfill, where it can’t (actually) degrade, because you can either (a) flush them, or (b) compost them or (c) throw them in the septic tank.

That the gDiaper refill goes down the drain with such a majestic swirl doesn’t of course mean it miraculously disappears. The concern about the diaper-in-the-landfills applies to the diaper-in-the-sewage as well. So what happens with it?

The sewage system brings the diaper to a wastewater processing facility, which separates potable water from sewage sludge. Many of these facilities produce “biosolids” out of the sludge. In the Grist interview, Jason and Kimberley Graham-Nye fill us in (bolds mine):

The EPA estimates that 16,000 publicly owned treatment facilities generate approximately 7 million tons of sewage sludge. About 80 percent of all sewage sludge is biosolids that is used as a fertilizer on farmland following treatment. It appears that at the North Bend, Wash., facility, 1.2 million gallons of biosolids were applied to forestland and grazing land last year.

They add that “the gDiapers flushable is complimentary to the wastewater facility’s production of biosolids”.

Great, but what about the SAP, the non-biodegradable part? It won’t break down, but there is very little of it in a diaper. Seventh Generation (on their FAQ)  specifies that the ratio is 30-50 grams of wood pulp to 5-15 grams of SAP per diaper. gDiapers use even less: less than 4 grams per diaper.

The promise is that this little bit of stuff “is inert and will settle out” (the Graham-Nyes in the Grist interview). It will get separated from the organic compost/biosolid-sludge and be washed away, and “if the septic is working properly, [the flushable] will break down completely and be discharged with the effluent”.

But discharged whereto? And how “inert” is it? Does it matter that it is such a small amount? … There you have it: the issue of biodegradability too comes down to SAP. 

  • “Chlorine free”: ECF and TCF, and does it matter?

Here’s another interesting fact. All the green diapers are “chlorine free”. Indeed, that is their main selling point. But what does that mean?

There is a difference between ECF (Elemental Chlorine-Free) and TCF (Totally Chlorine-Free).

  1. ECF pulp is bleached with chlorine dioxide instead of elemental chlorine.
  2. TCF pulp is bleached using any chemical other than chlorine, chlorine dioxide and hypochlorite.

The Alliance of Environmental Technology points out the following (bolds mine):

Research has shown the environmental risks to aquatic ecosystems from ECF bleaching are negligible and there is no toxicological difference between wastewaters generated from ECF-based or TCF-based bleaching.

But “more trees are required to make paper with TCF compared to ECF. With TCF, 3-4% less paper is produced from the same amount of wood compared to ECF.”

The AET also writes that (bolds mine):

In North America, ECF pulp production for papermaking increased to 53.1 million tonnes, totaling more than two thirds of the world market share. The balance is produced with some elemental chlorine. […] In the U.S., ECF has taken off, reaching 20 million tonnes in 2000 – accounting for 75% of U.S. production. TCF production lags far behind at less than 250,000 tonnes per year. […] In summary, with internationally acknowledged environmental parity between effluents from ECF-based and TCF-based bleaching processes established in 1994, the initial driving force for market demand for TCF was eliminated. Further growth of either product from 1994 forward depended on the traditional values of product quality and manufacturing cost. ECF-based bleaching produces higher quality with at lower costs. The market has spoken.

gDiapers’ Jason and Kimberley Graham-Nye want to make a difference (bolds mine):

We find it most frustrating that in the pulp industry, there is only one complete chlorine-free mill in the world, and they weren’t willing to supply us. As we grow, we would like to be an agent of change in the industry, and we hope to be able to source both FSC [Forest Stewardship Council] and completely chlorine-free fluff pulp. [Grist interview]

But why, if there is no difference between ECF and TCF? Forgive me my skeptical nature, but could it be because “non-Green” diapers such as Huggies are also using, for the main part, EFC wood pulp? Read, for instance, the 2006 sustainability report of Kimberly-Clark (which makes Huggies). It states (for all their products, not just diapers, bolds mine):

photograph of huggies diapers

Our preference is to purchase elemental chlorine-free (ECF) bleached pulp for use in our consumer products. This process uses chlorine dioxide rather than pure chlorine, reducing toxicity. During 2006, 89 percent of total pulp purchased was ECF and a further 7 percent was totally chlorine-free (TCF). Some of our South American and Mexican suppliers still use chlorine bleaching, accounting for around 4 percent of fiber use in 2006. We are no longer sourcing from one of these suppliers, are looking for an alternative to another and a third is installing a new ECF bleaching plant. Our own two pulp facilities, in Tantanoola, Australia, and Everett, Washington, U.S., use TCF and ECF bleaching technology, respectively.

So in the end, the question becomes: where does the wood pulp come from? If your child’s diaper has pulp that comes from a mill in China, can we be assured that it is ECF? And even if it is, has it been harvested with sustainability in mind? And how many miles has it traveled (how many barrels of oil has it soaked up) by the time it reaches your home?

  • Where does the wood pulp come from?

The Seventh Generation wood pulp comes from Europe, mainly Finland, and the diapers are assembled in the US (L. Chapdelaine, email 25 May 2007).

gDiapers’ Jason and Kimberley Graham-Nye in the Grist interview:

The inner core of the flushable is made of soft, fluffed wood pulp and super absorber. Like the outer material, the inside of the flushable comes from sustainably managed forests using an elemental-chlorine-free process. Our pulp supplier is actually certified by the Sustainable Forestry Initiative.

And gDiapers’ kim comments (on on the fact that the little gDiaper outer pants are “Made in China”:

As for the China issue…we certainly understand and respect where you are coming from. We work closely with China Labour Watch and in a few months will be opening the Happy Planet Mill. By increasing the standards of employment, compensation, conditions and respect, we hope we are contributing to a better China. If you prefer however, you can always buy the covers/pants from our Australian company at (made in Australia). I did want to point out however, that parents only need 12 pairs of little gs for the lifetime of diapering their child, but you will need 6,000 flushables….all made here in the USA.

I gather that the pulp for gDiapers comes partially from China, but that they are assembled in the U.S.  I’ve asked them for clarification and will update as soon as I hear from them. 

Also, a reader left a comment calling into question the credentials of the Sustainable Forestry Initiative (SFI) – the certifiers of sustainable practices that gDiapers so proudly mentions. It is certainly disconcerting to read that “The SFI is funded primarily by AF&PA members and other timber companies it certifies.  Timber companies and industry allies also continue to dominate the SFI’s governing board, which controls the SFI standards and other aspects of the system”… Read more about that here.

Lastly, Jason Hays at WF 365:

Our diapers contain wood pulp, sourced primarily from family farmed and sustainable managed forests, as part of the absorption materials. The product contains no recycled materials nor TBT, a common wood treatment agent. / The wood pulp comes from Scandinavia.  [email of 24 May 2007 / email of 31 May 2007]

TushiesDiapers, by the way,

are assembled in the U.S.A. With Domestic Materials & Scandinavian Certified 100% TCF-Totally CHLORINE-FREE  Woodpulp from Renewable, Sustainable Family Owned Forests!

  • Conclusion

If your choice of the right diaper for your child is also an ecological choice, then it pays off to look into the claims made by the companies, our culture, and our own assumptions. Once you start doing this, you may find that the issue is a complex one that grows with each newly learned bit of information. That’s ecology for you! An ecological decision is one that fits into that intricate web of life. Even if the above does not conclude which is the best choice, hopefully it leads you to some considerations that are helpful to you on your quest for the “right diaper”.

Comments? Suggestions? Please leave them here.

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  1. I found this post extremely interesting. I had no idea there was so much more than meets the eye to eco-friendly diapers. I can’t tell what the date is on the post–maybe it was some time ago. But, I was wondering if you had any information on Bambo Nature diapers. They are made in Europe and I have been purchasing them on Amazon. They seem to have many of the environmentally friendly characteristics mentioned in this article.

  2. all this time you wasted on this research & writing could have been used to wash a 1,000 loads of cloth diapers!

  3. I have been looking for the manufacturer in Mexico that produces these very good ecological nappies. can anyone help? I supply the creche/daycare with ecological nappies and to reduce costs I would like to get the disposable nappies directly from Mexico. We are located in France.
    I would be grateful for any suggestions.
    kind regards

  4. I have been reading a TON on these topics (the health and ecological sustainability of diapers) and this is one of the best posts that I have read. Thus, I have two thoughts: first, thank you; second, PLEASE consider continuing these updates as these products evolve and new products are brought to the market. You have such an investment in your knowledge base, updates beyond your childrens’ diaper years are so much more efficient than a newbie, sleep-deprived parent like me (who doesn’t even have a blog to share my research!!)

  5. Thank you, everyone, for the encouragement to update the research! However, my daughter is now 8 years old and is, thankfully, out of diapers. As such, it is hard to gain any hands-on experience with the new diapers or, I am afraid, to keep an interest in them, especially to pursue companies for information. I have to say, that back then, these companies were quite forthcoming. I encourage everyone to take my list of issues (SAPs, biodegradability, etc.) to write them questions, and to use that list to make your own list of priorities and go get informed.

  6. This article just made my head spin. I have a two month old and have been trying to use gdiapers with the reusable inserts. However, I have had much more luck avoiding leaks with their disposable inserts. I had a miniature freak out a week ago when I found the sodium polyacrylate balls on my child as I changed his diaper. I naively had no idea there is an absorbent polymer in the disposable liners. I emailed gdiapers and they educated me on the content of the disposables. I hope, that I can figure out how to use the reusable liners with less leaks…because I’m having a hard time staying on board with the disposables.

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