Web Analytics
Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
Leah
Leah

"Corn" Plastic: The Good, The Bad and The Ugly

corntastic

Creative Commons License Photo credit: Darwin Bell

“Would you like a bag with that?â€, asks the girl at the grocery store check-out. You glance at the couple of items purchased, and think of the walk home. She sees you hesitating and adds “It’s okay; these plastic bags are biodegradable. In fact, they’re made of corn!â€

“Perfect!â€, you think. Or is it?

The Good

This specific type of plastic is called PLA, or Polylactic acid. Simply put, PLA is created by fermenting the starch of corn kernels. Plastic made from PLA look and feel exactly like regular plastic, and PLA plastic bags are just as durable and lightweight as their non-PLA counterparts.

A renewable resource, PLA or “corn plastic†is 100% compostable. Under the right conditions, PLA breaks down in about one to six months in a commercial composter.

The Bad

But wait... what about in a landfill? As we all know, unless recycled, plastic bags that are used for groceries end up in city landfills, not commercial composters. In order to biodegrade, the PLA must receive sufficient amounts of oxygen, water, light and soil, which are not usually present in a landfill. Thus, it can take corn plastic just as long as regular plastic to break down—up to one thousand years. Unfortunately, that means that using corn plastic bags to line trash cans is no better than using regular plastic.

The Ugly

Although corn may be a renewable resource, there is only a certain amount of corn in the world to be used at a certain time. The use of corn for anything other than food seems a little selfish when we consider how much of the world’s population go hungry every day. For example, the use of corn for ethanol has increased the price, and the demand, of this important crop. Furthermore, corn crops require an enormous amount of pesticides and chemical fertilizers compared to other US-grown crops.

One other not-to-be-overlooked fact about corn plastic: regardless of what some companies claim, PLA can cause severe reactions to people who have corn allergies. Accordingly PLA plastic should be clearly marked as derived from corn.

The Verdict?

PLA plastic may be a step in the right direction when it comes to sustainability, it’s one piece of a much wider issue. As in most cases, all parts of the story need to be closely examined. Perhaps with further research, a better alternative can be found. For now, however, if corn plastic seems too good to be true, it probably is. Next time, take a reusable cloth bag to the supermarket.

User Feedback

Recommended Comments

Thank you for your excellent comments. No solution is perfect; PLA certainly isn’t the perfect answer to our plastic problems. There might be a place for PLA but consider this, PLA reduces food supplies, reduces corn or other food crop exports to countries that need them, PLA increases the usage of pesticides...and the big one is that PLA made from corn is made from genetically altered corn.....it isn't the edible kind. Let's just hope and pray that the corn they're using to make ethanol and PLA plastics don’t contaminate our food grain crops. We looked at PLA and Oxo-Degradables when we were looking for a fix for our standard PET plastic bottles. Both the PLA and OXO's had problems so we decided to do something different. We along with our partners have developed a PET plastic that is biodegradable. It will biodegrade in a landfill under anaerobic or aerobic conditions...If PLA makes it to the landfill it will be there for a long time, the ENSO bottle will biodegrade leaving behind biogases and humus.

Thanks for you comments.

Max

http://www.ensobottles.com

"Bottles for a Healthier earth"

Link to comment
Share on other sites

I'm new to your blog, so forgive if you've already mentioned this, but have you watched the movie 'King Corn'? It gives an amazing perspective on the industrialization of our corn crops and how so little of it is used as real FOOD anymore. I highly recommend it!

Link to comment
Share on other sites

This si a great idea for people who are still using the stupid 1-use disposable bags. A smarter idea is to ban them entirely, as is being done in some world cities.

The reason I like it is not about landfill space, but about the countless bags that end up blowing free. Many end up in waterways to float downstream and kill marine life. As the floating plastic from bags & bottle breaks into smaller pieces, it's accidentally consumed by fish and other marine life. It injures or kills some. Others become laden with the toxic compounds in plastic end end up on our dinner tables.

http://patagonia-under-siege.blogspot.com/2008/...

I'd like to see all plastics taken off the market and replaced with re-usable items or a plastic that breaks down quickly outdoors.

Link to comment
Share on other sites

"Let's just hope and pray that the corn they're using to make ethanol and PLA plastics don’t contaminate our food grain crops."

Ethanol and PLA can be made from the common 'field' corn grown in massive amounts already. This is generally GM corn (i.e. Monsanto RoundUp Ready). This is what the chicken or cow lived on before you paid to have it butchered for you, so any ill health is now concentrated in the tissue. GM corn is also available as 'sweet' corn, the kind people eat directly (eg corn on the cob).

Thanks to Monsanto and our corrupt US government, GM corn does NOT need to be labelled as such. Corn, HFCS, and other corn derivatives are in the majority of pre-packaged foods available in your supermarket. Anything from soda to babyfood to bread may have GM corn in it somewhere.

"PLA reduces food supplies, reduces corn or other food crop exports to countries that need them,"

We already grow enough food to feed EVERY person on the plant and have some left over. Why are people starving? Because 60-80% of our grain crops (depending on type) are thrown away as animal feed, not provided to people. Even better, our tax dollars (Farm Bill) subsidize the animal feed industry. We're promoting animalfeed/ethanol over growing food for people! So a little extra of this cheap surplus corn diverted to plastics isn't a big deal. If people really did care about excess pollution or 3rd world hunger, a much much bigger difference we can all make is cut back on the amount of meat/dairy we eat. A pound of grain can provide a pound's worth of food for people... a pound of steak took away 7-10 pounds of grain and gives us with a product high in sat fat, excess pollution, manure runoff, BGH, antibiotics, etc.

Link to comment
Share on other sites

I think you forgot to mention that a lot of the GM corn is being used to make ethanol...and it takes more than 1 gallon of petroleum fuel to produce a gallon of government subsidized ethanol. Monsanto corn is used to make plastic and ethanol and yes it is being fed to animals we eat and yes pollen from GM crops can be carried by the wind and infect other crops. Many countries are banning GM crops…good for them.

Max

http://www.ensobottles.com

Link to comment
Share on other sites

I think you forgot to mention that a lot of the GM corn is being used to make ethanol...and it takes more than 1 gallon of petroleum fuel to produce a gallon of government subsidized ethanol. Monsanto corn is used to make plastic and ethanol and yes it is being fed to animals we eat and yes pollen from GM crops can be carried by the wind and infect other crops. Many countries are banning GM crops…good for them.

Max

http://www.ensobottles.com

Link to comment
Share on other sites


Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Add a comment...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. We use cookies and other tracking technologies to improve your browsing experience on our site, show personalized content, analyze site traffic, and understand where our audience is coming from. To find out more, please read our Privacy Policy. By choosing I Accept, you consent to our use of cookies and other tracking technologies.