Study: Biodegradable products may be bad for the environment

May 31, 2011

Research from North Carolina State University shows that so-called biodegradable products are likely doing more harm than good in landfills, because they are releasing a powerful greenhouse gas as they break down.

"Biodegradable materials, such as disposable cups and utensils, are broken down in landfills by microorganisms that then produce methane," says Dr. Morton Barlaz, co-author of a paper describing the research and professor and head of NC State's Department of Civil, Construction, and Environmental Engineering. "Methane can be a valuable energy source when captured, but is a when released into the atmosphere."

And the U.S. (EPA) estimates that only about 35 percent of municipal solid waste goes to landfills that capture methane for energy use. EPA estimates that another 34 percent of landfills capture methane and burn it off on-site, while 31 percent allow the methane to escape.

"In other words," Barlaz says, "biodegradable products are not necessarily more environmentally friendly when disposed in landfills."

This problem may be exacerbated by the rate at which these man-made break down. Federal Trade Commission (FTC) guidelines call for products marked as "biodegradable" to decompose within "a reasonably short period of time" after disposal. But such rapid degradation may actually be environmentally harmful, because federal regulations do not require landfills that collect methane to install gas collection systems for at least two years after the waste is buried. If materials break down and release methane quickly, much of that methane will likely be emitted before the collection technology is installed. This means less potential fuel for energy use, and more .

As a result, the researchers find that a slower rate of is actually more environmentally friendly, because the bulk of the will occur after the methane collection system is in place. Some specific biodegradable products such as bags that hold yard waste and are always sent to composting or anaerobic digestion facilities were not included in the study.

"If we want to maximize the environmental benefit of biodegradable products in landfills," Barlaz says, "we need to both expand methane collection at and design these products to degrade more slowly – in contrast to FTC guidance."

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More information: The paper, "Is Biodegradability a Desirable Attribute for Discarded Solid Waste? Perspectives from a National Landfill Greenhouse Gas Inventory Model," was co-authored by Barlaz and NC State Ph.D. student James Levis, and was published online May 27 by the journal Environmental Science & Technology.

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User comments : 9

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extremity
5 / 5 (4) May 31, 2011
I'm not sure why this article got a 1/5 rating. It is simply informing us that based on this study, we may be handling biodegradable waste incorrectly. Although it does imply that when biodegradable objects are incorrectly disposed of, they may actually be counter productive to their cause. Which, frankly, is something that seems very important to know. There should be some follow-up and additional research by peers.
emsquared
2.4 / 5 (5) May 31, 2011
we may be handling biodegradable waste incorrectly.

I disagree. This demonstrates the myopic nature of the "Green" movement, which seems to only be able to focus on CO2 and GHGs.

Q: What is the biggest problem facing any given ecosystem?
A: Environmental quality degradation.

Q: What causes this degradation in quality?
A: Toxic pollutants (heavy metals, particulates, SO2, NOx, agri-run off, etc.), general mismanagement (i.e. spreading invasive species, over-fishing, unsustainable consumption of resource - like deforestation), habitat destruction (urban sprawl, farm-land, road proliferation, NON-DEGRADABLE WASTE-DISPOSAL, deforestation), and other by-products of a consumer driven society.

Q: What is not a threat to the environment?
A: A changing climate. Earth demonstrates this time and again. Nature has dealt with far more drastic changes in climate than what we are experiencing, yes, even more rapid, a changing climate is no danger to life on earth. The above things are.
Gilbert
3 / 5 (4) May 31, 2011
"This demonstrates the myopic nature of the "Green" movement, which seems to only be able to focus on CO2 and GHGs."

I believe that if you search further you will find that there are plenty of organisations focusing on more than just CO2 and GHGs

"Q: What causes this degradation in quality?"

perhaps in the answer to this you could also place "mis-handling of biodegradable waste"? .. as the article suggests
hush1
3 / 5 (2) May 31, 2011
Yes. The 'culpability' of any particular gas (or substance) is not an issue. As long as the 'solution' renders a 'pristine' environment...again.

I misplaced my biodegradable fuel rods again. Must be way to change that half life too.
astro_optics
1.8 / 5 (5) May 31, 2011
This just proves all over again , that the green movement has no clue what they are doing... They developed these biodegradable products a few years ago, just to try to to ban them now! The same applies to anything else they come up with... annoying little buggers!
hush1
5 / 5 (1) Jun 01, 2011
"They developed these biodegradable products a few years ago, just to try to to ban them now!"

I don't understand. Which biodegradables of a few years ago are the target of attempted bans now?
emsquared
not rated yet Jun 01, 2011
there are plenty of organisations focusing on more than just CO2 and GHGs

Organizations, sure. And those groups prevent being labeled as an environmentalist from being meaningless or even insulting.

But the popular, modern Green Movement - which is not organized at all, what you primarily hear in the media, almost exclusively focus' on carbon. Oh, and organics. It's a glorified marketing scheme. No need to change how you live, change what you buy. That is the prevailing message these days, it misses the point.

perhaps in the answer to this you could also place "mis-handling of biodegradable waste"?

No, this article is implying that methane release is worse for the environment than loss of habitat (i.e. longer lasting garbage). It's just not true and it's a disgusting misrepresentation of the most DIRECT threats to the environment.

Also, to those who down-rank with no reply, wanna present a counterpoint or are you just an intellectual coward?
Gilbert
not rated yet Jun 01, 2011
"This just proves all over again , that the green movement has no clue what they are doing... They developed these biodegradable products"

For one it would have been an entrepreneur or some company in the commercial sector that developed this technology. Just wanting to cash in on "the green movement"

"No, this article is implying that methane release is worse for the environment than loss of habitat"

Can you please point out to me where does the article compare methane to loss of habitat? I may need glasses but I can make out words on my screen and can't find loss of habitat anywhere?

I agree "the green movement" does mostly focus on Carbon, I am equally frustrated at that, I drive down from my house and see new areas of land being cleared everyday to make way for suburban sprawl and I find it unnerving. However I think you are defining "the green movement" in an incorrect manor. Was it not part of "the green movement" that was responsible for this artlicle? or any other research?
emsquared
not rated yet Jun 02, 2011
Can you please point out to me where does the article compare methane to loss of habitat?

The article is saying it would be better for the environment to have longer lasting garbage than quick-decaying garbage, because of it's methane release "schedule". They don't call out habitat-loss specifically but that would be the result of longer lasting garbage, they do state specifically as follows:
As a result, the researchers find that a slower rate of biodegradation is actually more environmentally friendly ... [than] "If materials break down and release methane quickly"