Digging Deeper:
Do Disposable Diapers Deserve the Bum Rap?

The Question
My niece recently had her first baby, and chose to use cloth diapers, including washing them at home. When I was bragging about her to a friend, he said that in an eco-analysis of cloth vs. disposable diapers, cloth were favorable but only by a slight margin. Can you help me get to the bottom of this? Is it environmentally sound to continue bragging about my niece?

The Explanation
Most diapers today fall into one of two categories: cloth diapers that can be washed and reused, or the more modern disposable diapers that are thrown away after a single use. Cloth diapers have the advantage of being soft, comfortable, and made of natural materials. Their disadvantages include their relatively poor absorbency and their need to be laundered. Disposable diapers were developed to overcome these problems.


Life-Cycle Analysis  

Making it
Cloth diapers are made of cotton, while disposables are made of plastics and petroleum byproducts. Though on the surface it might seem that disposables pose the bigger environmental threat, the differences are actually quite subtle. Producing cotton is not easy on the environment – growing the plants requires a good deal of water, pesticides and fertilizers. While it takes less energy to produce a cloth diaper than a disposable one, using cloth diapers for a year ultimately consumes more power because of the energy needed to wash the diapers.


Figure 1: Total energy used by each diaper type in one year. Feedstock and process energy includes energy used through cotton growing, material processing and diaper manufacture. It also includes energy used and embodied in bleach and detergent.

Newer types of flushable diapers, such as those made by gDiaper, try to bring you the best of both worlds: they combine reusable cotton exterior “pants” with flushable refills made of viscose rayon, a natural polymer that comes from trees. 

Using It
Now that modern cloth diapers have Velcro or snap closings instead of pins, both kinds are convenient and easy to use. Disposables however really give cloth diapers a run for their money in other ways: they’re much more absorbent and consequently require fewer changes, they are less messy, and they do not need to be a laundered, a process that requires water and electricity. 

Ultimately though, a parent’s greatest concern when choosing a diaper is making sure that it is comfortable for the baby, and keeps them dry, healthy, and free of diaper rash. Disposables, which contain several chemicals, may cause allergic reactions. With cloth diapers, one can almost completely eliminate the risk of diaper rash with frequent changes and proper laundering. Cotton also allows air to circulate more freely, making it more comfortable than most disposables.

Disposal
Both kinds of diapers pose significant environmental problems when it comes to their disposal or reuse – disposables take up landfill space and won’t biodegrade, while cloth diapers require an energy-intensive laundering process. Although changes in disposable diaper technology have made them less damaging to the environment in recent years, they still represent a burden to municipal landfills and continue to deplete natural resources. The U.S. Environmental Protection Agency estimates that in 2005 about 20 billion disposable diapers went into landfills across the country– that’s about 38,000 diapers discarded every minute. 

Reusable cloth diapers reduce the solid waste problem, but create a drain on electricity and water supplies. Commercial diaper laundering services, which wash diapers in bulk, can help mitigate this problem. Washing one child’s diapers at home for a year uses about 9,000 gallons of water, the equivalent of filling about 200 bathtubs, while commercial laundering systems use fewer than 6,000 gallons. Another way to reduce the energy cost of home-laundering is to line-dry the diapers instead of using a machine.

Washing dirty diapers ensures that the waste goes into the sewer system and can be treated in wastewater treatment plants, rather than ending up in a landfill where it may provide a breeding ground for disease. Untreated waste placed in landfills also has the potential to contaminate groundwater.

Similarly, the disposable liners of flushable diapers can be tossed straight into the toilet, where they also enter the wastewater treatment system.  Alternatively ones soiled only by urine can be safely added to a backyard compost heap, where they will biodegrade in 50 to 150 days.

The Cost
The cost breakdown between cloth and disposable diapers can be a little tricky.  While you can reuse cloth diapers indefinitely instead of having to buy new disposable ones, you’ll go through perhaps twice as many a day, and you’ll need to pay for the water and electricity to wash them. 

Disposables can cost anywhere from $50-80 a month, depending on how pampered your baby is. Commercial cloth diaper services cost around the same, while home laundering costs around $25-50 a month.

The startup cost for flushable diapers is high: a gDiaper beginner’s kit with two pants and 10 flushable refills costs about $27. Subsequent refill packs, which cost about 30 cents per diaper, are near the high end of the 18 to 35 cent range of ordinary disposable diapers.

Habits

The convenience of using disposable diapers is magnified when traveling – after all, who wants to cart around a bag of dirty diapers waiting to be washed?

For More Information
Some good summaries of the diaper debate can be found on the following websites:

Environment Canada: http://www.ec.gc.ca/EnviroZine/english/issues/45/any_questions_e.cfm

The New Parent Guide:
http://www.TheNewParentsGuide.com/diapers.htm

Institute for Lifecycle Environmental Assessment: http://www.ilea.org/lcas/franklin1992.html

Ohio State University Extension Fact Sheet – The Diaper Decision: http://www.mindfully.org/Plastic/Diaper-Not-Clear.htm

Information on how disposable diapers are made can be found at: http://www.MadeHow.com/Volume-3/Disposable-Diaper.html

More information on gDiapers is available at: http://www.gDiapers.com/ and at http://www.TheGreenGuide.com/doc/115/diapers

Click here to return to the Q&A.