View Full Version : Disposable diaper gel stuff - environmental impact?

02-25-2004, 03:00 PM
This is NOT (specifically) a cloth vs disposable question, mainly because I already use both with my kids. But I've had this question for a long time and I can't find anybody to even address it, much less answer:

If sodium polyacrylate (--CH2--CH(CO2Na)-- ) can absorb 200 to 300 times its own weight in water (including urine from babies, and water which percolates down through the layers of a landfill), and this water is not permitted to evaporate and return into the water cycle because the diapers are put into landfills, *and* this water is not accessible by plants whose roots would ordinarily be capable of extracting it....

What is the realistic cumulative long-term environmental impact of worldwide use of billions of such diapers yearly?

I actually worry about this.

02-25-2004, 03:13 PM
You don't live near an ocean do you?

Serious answer = I think that even if you have a relatively closed fresh water cycle you'd have to trap a lot of water with this stuff to make a difference to the local water table.

There's lotsa water on this planet. Trapping a few thousand tons isn't going to be catastrophic. That's not saying there wouldn't be better solutions to chemical diapers though.

The Scrivener
02-25-2004, 07:20 PM
IANASanitationEngineer, but... how much water retention could possibly happen with a diaper that's buried under layers and layers of garbage in a municipal waste dump?

On second thought, though, that heavily polluted "leach water" is probably best retained in situ, anyway. You don't want that toxic brew seeping anywhere near a drinking water source. Or agricultural land, or housing...

02-25-2004, 08:36 PM
What is the realistic cumulative long-term environmental impact of worldwide use of billions of such diapers yearly?

Don't bacteria eat the stuff?

I once left some of it in a jar of water for a few weeks. It turned milky, then the jelly consistency vanished.

Whenever I use it as a buffer in planting soil, it vanishes in about a year, and more is needed.

02-25-2004, 09:49 PM
A modern landfill is designed to minimize the percolation of water through the waste. Landfill have leachate recovery systems but these are expensive to operate - The landfill operator wants to minimize the infiltration of water. The waste is compacted in cells and capped with material with a low permeability. Vapor and water barriers are placed above and below the waste.

Here is one site (http://www.dec.state.ny.us/website/dshm/sldwaste/lfxsect.htm) from NY DEC - follow the links for additional info. This site (http://www.pawasteindustries.org/landfill.htm) is from PA.

States' Environmental Protection Branch (Department of Environmental Protection, Dept of Env. Quality, etc) usually have good information. Look in the solid waste section.

02-25-2004, 10:08 PM
Well, taking this information about modern landfills into account (and drawing on the information of William Rathje, who excavates landfills as an archeological sort of thing), I wonder if we are able to conclude that liquids that go *in* to the landfill, particularly if they are 'locked' into a chemical fixative, will *stay* there. We do know that a modern landfill is essentially an anaerobic environment, and that even biodegradable things (such as hot dogs, carrots, and newspapers) will frequently become mummified. But does this mean they dry out (the usual definition of mummification) and if not, where does the moisture go?

02-25-2004, 11:50 PM
Don't bacteria eat the stuff?

No. Like Chotii said, a landfill is an anaerobic environment. For the most part, things buried within them remain static-- they don't decay very much.

There's a fascinating book on this subject called Rubbish!: The Archaeology of Garbage. (http://www.amazon.com/exec/obidos/tg/detail/-/0816521433/qid=1077770255/sr=1-16/ref=sr_1_16/103-3684488-0839053?v=glance&s=books) It's a book about the University of Arizona's Garbage Project. (I highly recommend it.)

They're essentially garbage archaeologists, studying the contents of landfills. What they discovered was surprising. They found that organics one would expect to rot away, such as beef and vegetables, were still recognizable after fifty years.

(The book also discusses trash/consumption habits of Americans. For example it was discovered that people waste more of a food item during a shortage of that item. People also tend to exaggerate the amount of food their family consumes, and recycling campaigns actually make people throw away more of the item that is the focus of the campaign.)