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Be Green

Being green or being ripped off?

Erm, just because you can't see it doesn't mean it ain't there. Read on...

Have you been spending extra money buying biodegradable or oxo-degradable plastic bags? You know, for trash or to pick up after your pooch... I know I have. And they ain't cheap. A pack of 30 Scoopies brand poop bags will usually cost about $3.45. But then, the other day, a colleague brought in a pack of 45 "biodegradable" poop bags that she picked up at the dollar store! They had the same "oxo-biodegradable" certification as the ones I was buying. So why was I paying so much more? Oh, and what about those nifty compostable bags made of PLA (corn)? Aren't they better than your average plastic trash bag?

So here are the questions I ask:
1. Is it worth paying extra for biodegradable plastic?
2. Is there even such a thing as biodegradable plastic? And what's left when it degrades?

I spoke to Élyse Rémy who works with the National Institute for Environmental Health (L'Institut National d'information en Santé Environnementale). She knows so much about plastics that she's come to be known as "Madame Plastique". She had some pretty shocking things to tell me!

Oh, and if you're a member of the "I take plastic shopping bags at the grocery store because I use them for trash and to pick up after my dog" party, this piece might change your mind.


Know thy enemy
Okay, plastic in and of itself isn't a bad thing. In fact, its lightweight, durable and flexible properties have made it something we can't live without. But therein lies the problem. We've become overly dependent on something that has come to signify disposable even when it actually doesn't ever degrade and disappear!
Before we go any further, it might help to know your plastic. It's unfortunate the document is available only in French, but if you can read French, it's extremely well laid out.

If you can't read French, here's the gist:
1. PET (PETE): Polyethylene terephthalate. Eg. 2-litre soft drink bottles, water bottles, cooking oil bottles, peanut butter jars.
2. HDPE: High-density polyethylene. Eg. Detergent bottles, milk jugs.
3. PVC: Polyvinyl chloride: Commonly found on plastic pipes, outdoor furniture, siding, floor tiles, shower curtains, clamshell packaging.
4. LDPE: Low-density polyethylene: Commonly found on dry-cleaning bags, produce bags, trash can liners, food storage containers.
5. PP: Polypropylene: Commonly found on bottle caps, drinking straws, yogurt containers, legos.
6. PS: Polystyrene: Commonly found on "packing peanuts", cups, plastic tableware, meat trays, take-away food clamshell containers
7. OTHER: This plastic category, as its name of "other" implies, is any plastic other than the named #1–#6, Commonly found on certain kinds of food containers, Tupperware, and Nalgene bottles.
8. PLA: Bags made from cornstarch (often sold as compostable)
Source: wikipedia

Image courtesy Ecoworldly.com

Okay, so you already knew that. But here's the part they don't always tell you:
Most of that plastic never goes away. What's worse, there's now 6 times more plastic than zooplankton in the Pacific. It says so right here (and Rémy confirms the stat). The plastics industry will rush to tell you that plastic by itself is an "environmentally benign" compound. This is true. It doesn't hurt or help your health by itself. HOWEVER, many of the additives commonly put into plastic to give it its flexibility or durability... them's a whole other story. Bisphenol-A anyone? How about phthalates?
It gets worse: in the ocean, plastic acts as a sponge and attracts some serious toxins known as Persistant Organic Pollutants (POP). Dioxins are a good example. What happens is that the wee fishies consume the plastic with the POP, the bigger fishies eat the little ones and... well, you know where we are on the food chain, hey?

But what about biodegradable plastics?
We're doing good, right? We're shelling out the extra cash for bags that look and feel suspiciously like plastic, but have reassuring signs on them saying "Oxo-degradable" or "Compostable". What does that writing really mean?

This simply means it needs oxygen to break down.
BIODEGRADABLE: Needs microorganisms like bacteria or molds to break down. Usually in the presence of oxygen.
OXO-BIODEGRADABLE: It breaks down in two steps. First, oxygen helps dissolve the plastic to form a "wet" surface that's more hospitable to microorganisms (which then finish the job).
PHOTO-DEGRADABLE: Breaks down in the presence of light.
AQUA-DEGRADABLE: Needs water to break down.
COMPOSTABLE: Suitable for industrial composts (unless specifically labelled for home or backyard composts)

Sounds good, right? But remember that little ol' "O" word... oxygen? Guess what's not available in most landfills. Heck, landfills are specifically built to inhibit interaction between the dump and its environment. Therefore, in a landfill there is no essential difference between a "green" plastic bag and a regular ol' sack of plastic. . We wuz had!

I know, my heart is breaking too!

And that was before I asked what the bags actually biodegrade into. My pack of Scoopies says "Breaks down to CO2 and H2O in 18 months". Are they lying? No, they're not. In a perfect setting, with tons of oxygen and microorganisms available, that's exactly what will happen. There will, however, still be microscopic particles of plastic left over that will absorb toxins and make their way into the food chain. THIS IS BEST CASE SCENARIO! I'm sorry, my mind is boggling a little.
And of course, as I've mentioned, very few of those doo-doo sacs actually get to decompose at all.
Does this mean you should leave your dog's poo lying about or leave the bag on the street? ABSOLUTELY NOT! Dog poo is full of micro-organisms that can leach into the water table and cause communicable diseases. And you don't want plastic lying about where birds and other unsuspecting wildlife can mistake it for food. Like these cows in India.

What about those compostable ones? They biodegrade! Hell, they often break apart while I'm using them!

Okay, PLA or cornstarch is controversial. Here's what's not so great about them:
1. They often require very specific conditions to break down. Anyone who has used them in a backyard compost can attest to this--they don't break down easily. Except perhaps in industrial facilities where temperatures are higher.
2. Waste: Think about this: we're basically growing corn just to throw it away. These bags aren't made to last. They're made for single uses. Now think about all the water and pesticides and petrol (for transport) used to make those bags in the first place. It just doesn't add up.
3. Food: Also, we're displacing food and animal feed for this disposable product. Which means that more land will be cleared for food farms. Which may mean more deforestation for monoculture.
4. Contamination: If a PLA bag ends up in your regular plastic recycling, it can bring down the price of that recycled plastic. It basically acts as a contaminant.
5. Clogging waterways: PLA doesn't break down in water. So fish and other sea creatures suffer from it.
6. No oxygen, no degradation: Same as the other bags. In a landfill, it's just going to sit there. Maybe less long than other plastics, but still, it's not going anywhere fast.

So are you saying I shouldn't buy biodegradable bags?
Yes, BUT, it comes with a condition. The trick is to use as little of ANY plastic as possible. This may be counterintuitive, but it makes better environmental sense to buy little regular plastic poop bags or giant trash bags than to use free shopping bags. Why? Because you can fit much more garbage in a big bag than a little shopping bag. So using shopping bags actually boosts your overall consumption of plastic. Just say no! As for poop bags, again, these tend to be eensy, so you're using less plastic per poop than if you use a shopping bag.
Bottom line, stop using plastic shopping bags.

Image courtesy The Go Green Blog.

Here's how
It's a simple answer with very hard consequences: reduce your dependence on plastic. Buy 6 organic cotton re-usable bags (or pay $.99 at the grocery store for one of those recycled plastic tote bags) and BRING THEM EVERYWHERE. Keep one folded in your purse (These bags are perfect for this... and stylish!). Keep some in your car. Put them on a hook by the door and USE THEM! And if you end up at the grocery store without a bag, stay committed. If you're buying just a few items and can carry them in hands and pockets, great! If not, charge yourself a "forgetfulness tax" and buy a 99 cent reusable bag. This is what I did to get myself into the habit. Believe me, once you've had to buy a couple of those bags, you begin to remember. Now I always have some folded away in my backpack. Haven't used a plastic shopping bag for 13 months (and counting...)

Have you given up plastic shopping bags? How did you do it? Do you have a favourite product to share?
Leave me a comment or call the Talkback Line: (514) 597-5626

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Comments (6)

Barbara Dylla


I used to live in Switzerland where people brought their shopping bags and carts because, at that time, grocery stores simply didn't provide plastic bags [sturdy paper bags, maybe, but there was a 15- or 20- cent charge for one]. Like anything, when you do it often enough, it becomes a habit to bring your own bag(s). I always carry at least one bag (that conveniently folds up into a pouch) for impulse purchases, but take my backpack when I'm going food shopping. What's really handy is a bottle bag (SAQ, LCBO) because you can put different items in the individual compartments. It keeps items separate, especially if you have breakables (jar, bottle, eggs) or delicates foods (soft fruit, tomatoes, etc.)

Posted February 23, 2009 01:20 PM

pierre cyr


Hi, i disagree with the size of the bag.

If you use a smaller bag, you will need more bags to cary your loads. The bigger the bag means less plastic in the end.

Also, i don't bye garbage bags anymore, I simply use the grocery bag as a garbage bag. I figured why buy a bag to use it as a garbage bag... it's just money out the window. When they decide to make a REAL green bag, i'll buy it.

Geeta says:
I understand what you're saying about not wanting to spend money on plastic when you're getting some for free. But you have to understand: if you use much more plastic overall if you put your garbage out in little bags as opposed to one big one. The idea would be to create as little garbage as possible (by composting and recycling what you can) and then waiting till a big bag is full before putting it on the curb.
Does this make sense? This will cut your overall plastic use significantly. So please, try not to ever use plastic shopping bags. They don't last long (as bags) and then persist for ages in the environment.

Posted February 23, 2009 07:12 PM



Thank you for the back-up on "bio-bags"/grocery bags!! I've been talking myself blue about this!

Can you look into 1 other problem with the "green" push? Compact flourescents. Look into disposal requirements, how they CANNOT be placed into regular garbage. Special handling required, what to do if they break - DO NOT handle them. They are not the answer to all our energy problems. Dimmers, reducing wattage, and just plain turning off lights are a better answer.

Don't get me wrong - we try to be as green as possible. Recycle, reuse, reduce heating, reusable bags and crates for groceries AND GIFTS,one car family, walk whenever possible, better appliances, minimize electrical usage: use the computer to listen to radio while I'm on the computer, etc... we aren't ignoring the problem at all! I just want to make sure a "solution" is all it's cracked up to be.

The way people jump onto a bandwagon without vetting the technology first just annoys me! Thank you Geeta, for sorting it out for people.

Posted February 24, 2009 02:53 PM

Alison Proteau


Thank you for the insight into those tricky bags. I was eyeballing some in the store the other day! You saved me the wasted cash.
What would be VERY NICE is if the municipalities here would get going on municipal composting facilities like in Nova Scotia. This is something I really miss and cringe at how much more waste is going out in our regular garbage compared to what we put in it back in NS. I have a back yard composter but it only takes so much and is pretty useless during the winter.

Posted February 27, 2009 01:40 PM

Mark Eccles


RE: biodegradable bags
Obviously you can buy it once, and test it yourself. See if sunlight breaks it down ( a bit on the outside of a window), see if water breaks it down (like food, hard uncooked rice or pasta does get soft in water), see that if placed in the compost-dirt, the rate of change that takes place as biodegradable plastic crumbles and strength as a bag breaks down.

Geeta says:
You're sort of right, Mark. The thing is, as I've explained in the entry, just because the plastic appears to break down doesn't mean the molecules go away or become inert. The problem with much of the plastic that's in the ocean today is that it never fully breaks down--it simply becomes smaller versions of itself. And in the sea, plastic acts as a sponge for all sorts of chemical nasties. Then it gets eaten by itty bitty fishies and allllll the way up the food chain to where it affects our health.
Every expert I've spoken with on the subject seems to agree (if grudgingly), when it comes to plastic, just say no (whenever possible).

Posted March 9, 2009 12:06 PM

huw jenkins


interesting article!
while i agree that compostable plastic is not the best solution for many reasons quoted, it's my understanding that the difference between compostable plastic to degradable plastic (be it bio, oxo or photo degradable) is that the compostable plastic will not release toxins during it's life, whether it has broken down completely or partially. this should mean that it is safer for the food chain, and for those of us who love seafood. have you encountered any information to disagree with this?

Geeta says: Actually Huw, I have not. In the sense that the plastic itself may not be toxic. The process of raising the corn is a whole other story. Pesticides, deforestation, water overuse, etc are all factors there. Not to mention the process of chemically converting the corn to bags and then shipping them out.
For sure each process is going to have SOME footprint. But the benefit of using a reusable bag is that whatever it's initial footprint is, the overall impact is vastly reduced because you're reusing it SO many times (instead of getting a fresh bag every time you run to the grocery store).
As for trash bags, frankly, there aren't many options. The only way to really make a difference is to do your best to reduce any and all packaging waste and throw out as little as possible in the trash. Hope this helps!

Posted May 13, 2009 04:08 PM

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