The blog formerly known as   Fake Plastic Fish
November 2, 2007

Hidden Plastic

A lot of plastic hides in objects that many people don’t realize contain plastic: plastic that coats and lines cartons and cans and caps and lids. Plastic that can’t be separated from the material it’s attached to. Here’s a rundown of some of them.

Paper milk cartons are lined with two layers of polyethylene, inside and out. Many people are under the mistaken belief that these cartons are waxed. In fact, although the original paperboard milk cartons were coated with paraffin wax, they haven’t contained wax since the 40’s when polyethylene became the waterproofing material of choice.

Here is a diagram of how they are made, directly from Elopak’s web site.

The point is that if it’s made from paper these days, and it holds liquids, it’s generally going to be coated with plastic. As far as I know, there’s no ice cream container that’s not coated with a petroleum-based plastic, although there are manufacturers experimenting with bio-based plastic coatings.

So choosing paper cups and paper plates does not necessarily mean plastic-free. Cups are always coated with a layer of polymer film to make them waterproof. Plates may or may not be coated with plastic. You can tell if they are shiny or not and if wet food soaks through them or not. Georgia Pacific’s Dixie Brand (pictured) contains a “Soak-Proof Shield.” Their site does not reveal what the shield is made from, but you can be sure it’s plastic.

There is a new paper cup being used by Tully’s and a few other coffee houses called the Ecotainer. It’s coated with NatureWorks PLA, a corn-based plastic, rather than petro-plastic. Hopefully, this is just the beginning of new, more environmentally-friendly options, as they are fully compostable (the cups, that is; not the lids.) Still, disposable is disposable; NatureWorks PLA is produced by Dow Chemical and Cargill; growing corn in this country, most of which is GMO, is fraught with its own environmental hazards; and bringing your own is always the best choice.

Moving on from paper products, we come to cans. There’s been a lot of news lately about the fact that most food cans are lined with polycarbonate, which has been found to leach Bisphenol-A. And the few BPA-free cans are lined with another kind of plastic coating. So buying canned foods is not a way to remain plastic-free.

Neither is buying canned soda! Aluminum soda cans also contain a BPA plastic lining to prevent the soda from reacting with the metal. See for yourself in Steve Spangler’s Inside The Soda Can demo.

So, what kind of food container is really plastic free? Glass? Not quite. The lids of glass jars are lined with plastic as well. Some Mason jar lids don’t seem to contain plastic, but all of the twist-off ones do. See my discussion of the differences between jar lids.

And metal twist off caps are not plastic-free either. This photo shows a twist-off wine cap. Wineries have been switching to these lately as an alternative to cork. However, these caps are lined with PVDC, a possible hormone-disruptor, which is yet another reason to stick to natural cork stoppers, especially since producers are taking new measures to make sure natural corks do not develop mold.

Confession: I do indulge in the occassional pint of Straus’s local, organic ice cream, and I do use glass jars with those plasticized lids.

I’m not listing these things to scare you or make you think you have to avoid everything. But I think it’s a good idea for us to be mindful of all the plastic we use every day and to try and minimize our consumption as much as we can. I always think it’s better to be educated than blissfully ignorant.

Every item on this page is either recyclable or compostable where I live in Oakland, CA. The question to think about is what happens to all that plastic? As we know, it doesn’t biodegrade. It’s all still out there somewhere, even if the metal has been made into new cans, the paper has been pulped into new paper or broken down into new soil. The plastic’s still there in our environment. I don’t know the ramifications of this fact. But I do think it’s important to keep in mind.

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[…] We’ve also generated more plastic waste from pre-PFJ purchases. About half of it came from food, most of which we can replace with low-plastic alternatives from bulk bins or in glass bottles and jars. The other half was packaging from kitchenware and other household items purchased before July, and like our experience at the hardware store last week I suspect that finding plastic packaging-free versions would have been very difficult. Our pre-PFJ plastic weighed in at 200 g, of which 50 g came from a can of tomatoes — did you know cans are lined with plastic? The stuff… Read more »
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1 year 8 months ago
@Eco Yogini I know your post is old, but wanted to comment in case someone is looking in the future.  If a cup is actually compostable, as in it meets the ASTM standards for compostability and is tested and certified by BPI (Biodegradable Products Institute,, then it will break down in compost facility that follows the correct management practices for time, temperature, oxygen. The temp is no higher than a normal compost pile naturally generates (around 131º) and in fact, if a compost pile gets too hot (over 200º) it will spontaneously combust.  The certified stuff is not and never… Read more »
1 year 8 months ago
@Eco Yogini I know your post is old, but wanted to comment in case someone is looking in the future.  If a cup is actually compostable, as in it meets the ASTM standards for compostability and is tested and certified by BPI (Biodegradable Products Institute,, then it will break down in compost facility that follows the correct management practices for time, temperature, oxygen. The temp is no higher than a normal compost pile naturally generates (around 131º) and in fact, if a compost pile gets too hot (over 200º) it will spontaneously combust.  The certified stuff is and never… Read more »
1 year 8 months ago
@CindyW I realize your post is quite old, but in case others are reading in the future, this word “biodegradable” is a huge problem. Biodegradable is an unregulated word that means little, everything biodegrades/degrades with enough time. Compostable is the important term, it is a regulated and means a certain set of standards have been met. The product must go to a facility where it is composted, which is an aerobic (needs oxygen) activity. That said, yes, most things that end up in a landfill, no matter what they are made of, stick around for a LONG time. In fact,… Read more »
Miss Trust
1 year 8 months ago

So If you really want to be poison and plastic free you must find a virgin planet in a galaxy far away, cause this ones gonna stay contaminated till the sun blows up. Hard to believe it only took 150 years to **** it up!

2 years 2 months ago

What disturbed me most today in my search about BPA’s and phtalates, is that is seems that especially hospitals are dealing large amounts in bloodbags, intravenous apparatus, respirational equipment & so on. Also some pills with for instance omega3 have high phtalates content.

2 years 2 months ago

@Rebecca I’m reading in on BPA and phtalates, and … well, as long as the milk is not obtained by hand …. be sure the phtalates levels are very high, meaning that before it hits the bottle, it’s being transported and pasteurized, mixed etc, in probably loads of plastic (lined) containers and pipes :o/

2 years 4 months ago

@Rebecca I only like very weak tea and I can taste if the water was boiled in a plastic kettle especially if it was boiled and left to stand.

2 years 4 months ago

I’m trying to find out if buying butter beans (for example) in cardboard cartons is safer than buying them in cans. I thought that the cartons would be safer but now I’m not sure. Does anybody know please?

2 years 6 months ago

I really don’t think u can get away from all this plastic coating and I drink from paper cups at work so I am putting all this crap into my body. I thought about bringing in a ceramic cup but cause its a hospital environment I don’t think this would be allowed!

2 years 7 months ago

Really appreciate you sharing this article.Much thanks again. Great.

2 years 9 months ago

This post is really something special and more information gathering by your site and also useful. I want to some more information thanks.

2 years 10 months ago

Thank you ever so for you post.Thanks Again. Much obliged.

2 years 10 months ago

I have been reading a lot of blogs and forums lately. Some are actually informative some are amusing and some are a genuine chink up. I’ve got to accept it, large job on this blog, I’ll be
certain to ascertain back from time to time

2 years 10 months ago

I am pleased sure this post has helped me save many hours of browsing other similar posts just to find what I was looking for. I bookmarked this blog a while ago because of the useful content and I am never being disappointed. Keep up the good work Just I want to say: Thank you!

Currency Meter
2 years 10 months ago

I am joyous to find so many good issue here in the mail composing is simply great thanks for distributing.

2 years 10 months ago

I do wish there were more persons like you round on the interwebs. Not many persons are very cautious with their phrases, including myself sometimes. I have written things I would love to take back.

3 years 2 months ago

Consider that even when they were waxed, it was probably paraffin-based wax and therefore petroleum/plastic even then.

3 years 2 months ago

@D Yep.

3 years 5 months ago

This is a good post. This post gives truly quality information. I’m definitely going to look into it. Really very useful tips are provided here. Thank you so much. Keep up the good works.

3 years 5 months ago

I am very happy to find this blog.Thanks for creating the page! Im positive that it will be very popular. It has good and valuable content which is very rare these days.

4 years 7 days ago

I am thinking that the butcher paper with the shiny side is probably plastic, eh?

5 years 7 months ago
Gees….. lids from glass jars…. ?? ” Wax” on paper. More food for thought. Thanks for promoting the use of cork. Portugal being the biggest exporter of cork can really do with the business. Also, the trees are beautiful & cork is completely sustainable. The trees don´t get cut down, they just have a “hair cut” every ten years. Natures magic. I never knew that before I saw them. (you probably do) But sometimes you don´t know until you open the bottle & they surprise you with a plastic “cork” . It should have to be labelled.
5 years 7 months ago
Thanks so much for pointing me to this post. The milk carton thing is a revelation, although not a surprising one. And I’m not just being cynical… I’ve always sworn that milk in anything but glass tastes like plastic to me. I seem to have very finely tuned plastic taste buds because I can taste the plastic in any liquid that came out of a plastic container (with the possible exception of something like soda or juice that already has such a strong flavor.) I’ve always refused to drink bottled water unless it was Perrier or something in glass because… Read more »
5 years 10 months ago

hey do you by chance know the difference between waxed paper cups and plastic lined paper cups? because i’m doing a science fair on it and i want to know the difference

Eco Yogini
7 years 4 months ago

Actually, my issue here is that the “compostable” cups are not actually compostable. If you put that cup into your compost unfortunately it won’t actually biodegrade. Those cups need high energy heat to process and most industrial systems actually can’t accept them. For example, Halifax NS has several coffee shops that offer these “green” alternatives… and the city (who is provincially mandated by law to compost and recycle) cannot process them. They go in the landfill… :S

I was interested in knowing more about what layers were in the non-recyclable paper cups though :) Thank you very much!

7 years 7 months ago

Great blog! I would LOVE for there to be a comprehensive list of plastic free cans. Would you like to start it off? :P

8 years 7 months ago

Thank you for creating this blog. The environment is so toxic due to more than 100 years of unbridled scientific inventions that were supposed to improve our lives. The only way to even have a chance at healing the Earth is for everyone to get informed about responsible consumption and start acting as caretakers of this planet. Thanks for doing your part.

8 years 9 months ago

No, no, not Straus Ice Cream! I LOVE the ice cream.

I wonder what your thoughts on corn-based biodegradable coating. From what I understand, it only degrades under ideal situation – exposure to sun and air and above certain temperature. If it is thrown into the regular trash bag and landfilled, it does not bio-degrade for a long long time. True?

8 years 9 months ago


I’ve been using the ecotainer cups for dh (he can’t seem to hold on to a reusable coffee mug for more than a day) and he LOVES them! I also use the corn-based drinking straws for the kids. They both hold up very well and then get tossed in our compost bin. I’ll let you know next spring how they break down.

As always, thanks for all the great info!

8 years 9 months ago

great post! thanks, Beth!

here’s another article on the canned foods:

8 years 9 months ago
Thanks for this info. I had asked about the wax before and you said it was plastic. Sure enough, it can’t be scraped off with a fingernail as was the case with the wax. I think that the cardboard boxes that produce gets shipped in still are wax coated. Until recently we were using firelogs made from shredding and compressing the empty boxes. They made great firelogs but the company that made them folded so now I am on the lookout for Java Logs. Oh, one last item. What do you know about Tupperware? They must use some special plastic… Read more »
8 years 9 months ago

Hmm…so probably when we burned “wax” cartons in the Girl Scouts for fire-starters, that wasn’t a good thing, eh??? I’m glad that at least the metal can be recycled around the plastic, but still–that’s a lot of plastic!

8 years 9 months ago

Wow, thanks for the info. And here I am thinking I’m avoiding plastic when I buy glass containers.