
If you recycle you’ve probably turned over a plastic container to read the number on the bottom, the one surrounded by the little recycling symbol. Many recycling programs depend on these numbers to tell you which plastics you can and can’t recycle.
Do you know what these numbers mean? Did you know these numbers tell you which plastics are considered safe and not? You may recall there was a big scare recently over BPA plastic leaching chemicals into water bottles and baby feeding bottles, after studies showed that BPA mimics estrogen and interferes with hormone levels.
There are seven numbers you will find on plastic containers, reflecting seven different types of plastic available in the market. The number is a resin identification code associated with the type of plastic used in the container. Some plastics are healthier and more environmentally friendly, some less so. Some are easier to recycle, some less.
Here’s your guide to what the numbers mean, whether they’re safe, and how easily recyclable they are:
Plastic #1: This is polyethylene terephtalate, also known as PETE or PET. Most disposable soda and water bottles are made of #1 plastic, and it’s usually clear. This plastic is considered generally safe. However, it is known to have a porous surface that allows bacteria and flavor to accumulate, so it is best not to keep reusing these bottles as makeshift containers. This plastic is picked up by most curbside recycling programs.
Plastic #2: This is high density polyethylene, or HDPE. Most milk jugs, detergent bottles, juice bottles, butter tubs, and toiletries bottles are made of this. It is usually opaque. This plastic is considered safe and has low risk of leaching. It is also picked up by most recycling programs.
Plastic #3: This is polyvinyl chloride, or PVC. It is used to make food wrap, bottles for cooking oil, and plumbing pipes. PVC is a tough plastic but it is not considered safe to cook food near it. There are phthalates in this material–softening chemicals that interfere with hormonal development. You should minimize use of #3 plastic around food as much as possible. Never cook using food wrap, especially in a microwave oven. If the wrap is listed as microwave-safe then I would still not let it touch the food while using it in the microwave. #3 plastic is rarely accepted by recycling programs.
Plastic #4: This is low density polyethylene (LDPE). It is used to make grocery bags, some food wraps, squeezable bottles, and bread bags. This plastic is considered safe, but is unfortunately not often accepted by curbside recycling programs.
Plastic #5: this is polypropylene. Yogurt cups and similar wide-necked containers are often made from it, as well as water bottles with a cloudy finish. You’ll also find it in medicine bottles, ketchup and syrup bottles, and straws. This plastic is also considered safe, and is increasingly being accepted by curbside recycling programs.
Plastic #6: this is polystyrene, or Styrofoam, from which disposable containers and packaging are made. You’ll also find it in disposable plates and cups. Evidence is increasingly suggesting that this type of plastic leaches potentially toxic chemicals, especially when heated. I suggest avoiding the use of #6 plastic as much as possible. It is difficult to recycle and most recycling programs won’t accept it.
Plastic #7: This number basically means “everything else.” It’s a mixed bag, composed of plastics which were invented after 1987. Polycarbonate falls into this category, including the dreaded BPA. So do modern plastics used in anything from iPods to computer cases. It also includes some baby bottles and food storage containers which resist staining. Use of #7 plastic is at your own risk, since you don’t know what could be in it. You should dispose of any food or drink related product, especially for children, that is known to contain BPA. I personally also view any other food or drink container made from #7 plastic with a good deal of suspicion. It is difficult to recycle #7 plastic and most curbside recycling programs won’t accept it.
To summarize, plastics #2, #4 and #5 are generally considered safe. Plastic #1 is safe too but should not be re-used due to the risk of growing bacteria. Any other plastic should be used with extreme caution, especially around food or drink. The risk is even greater when heating food. For microwaving in particular, remember that microwave safe containers aren’t necessarily healthy. They just won’t melt. In general, it’s better to avoid microwaving plastic entirely and stick to glass.
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{ 17 comments… read them below or add one }
They need to adopt a similar scheme in England. As far as awareness goes, it’s far better in North America and kudos for spreading the education. Digged!
Thank you!
I keep forgetting that I should say “in the US…” for these articles because of international readers like yourself coming by.
No problem!
It’s great awareness and I believe the article is truly borderless in that regard. I look forward to the next set.
I am researching the potential of a similar method of designation here in the UK and with luck we can try something along the same lines.
Recycling here has a long way to go, but its popularity is growing and some local councils and governments are really taking charge and changing perceptions of how easy it really is.
Just so you are aware, the #7 catch all category also includes bioplastics made from corn and sugarcane. I think most of those items are usually marked though (they like to show that they are bioplastics on the container).
I just hate to see folks avoid the bioplastics and biodegradable plastics since they are lumped together with everything else.
Great point, Karen–we definitely want to encourage the use of bioplastics and biodegradable plastics. It’s too bad they’re lumped in with the bad plastics in #7, but having them specially marked should help.
I’m not saying “don’t use” bioplastics and biodegradables, but in many cases (at least in the UK) these things won’t break down under normal conditions. As they need high temperatures and (for some) lots of light, they really need to be commercially composted to degrade properly. If they end up in landfill they will likely not find the right conditions, and instead decay anaerobically and produce methane. It’s because of this, that UK drinks manufacturer, Innocent, stopped using biodegradable bottles and moved to recycled ones. I’m hoping science will develop so that this won’t be a problem, but I’m not sure we’re there yet.
Hi,
What is 641R mean under the plastic serving trays that used at schools? What kind of plastic is this? Is it safe? Thank you so much for any help!
Havva.
I don’t recognize 641R and am not sure it’s related to recycling. Look for a number surrounded by little arrows (mobius loop), that would tell you what kind of plastic it is.
Hello I am just looking into purchasing an automatic spouter that is made of PET plastic. This would be used to grow sprouts from seeds approx. 3-5 days. What would your thoughts be on using this machine. I read that this plastic is not good for prolonged use however the manufacturer has guaranteed that it is food safe? Thanks
Deanna, the issue with PET #1 plastic is that when you re-use it as a water bottle it eventually accumulates bacteria that you should not be ingesting. It’s therefore advisable to recycle it once you’ve consumed the bottled water.
I’ve not used an automatic sprouter, and I can’t say whether the same bacteria issue would be present. Personally, I would not use it because of the unknowns….I tend to be suspicious of any manufacturer claims. :)
This information was really helpful because was very curious about this problem but this topic doesn’t state why the recycling companies don’t recycle plastic #3-7? Can someone please tell me why they do not recycle these plastics
Just wondering about the safety factor when children chew on plastic straws and plastic cups/sippy lids? We have some #5 drinking containers with attached straws and my little ones tend to chew on them. Should they be discarded as soon as there are marks? How about typical disposable straws?
Thanks for your time :)
Ally: I honestly never thought about straws. According to Recyclenow.org they are made of #5 plastic. #5 plastic you find in the straws or sippy cups is generally considered safe, although for children I would probably not push the envelope. I personally would discard (recycle!) these products once kids started leaving teeth marks on them, but I would otherwise keep using them.
Paras: the plastics you mention are often not recycled because they are made of plastics that are more difficult to break down and re-use. Not all plastics are the same, some are easy to break down and some are very difficult. #1 and #2 tends to be the easiest to process, although recycling programs are quickly growing to encompass the other numbers as technology advances and the process becomes easier.
The #3 plastics that are used to wrap food…I just wanted to be sure I understand the issue. Is it that you shouldn’t heat it ? Is it safe as a wrap? Just confused b/c most meats are wrapped in it at the stores. It’s a bit disconcerting if it shouldn’t be in contact with food at all.
There are always unknowns, but the concern is primarily around heating it. I never, ever heat food in the microwave while it’s wrapped in any kind of plastic wrap. But I do use plastic wrap freely for things like putting stuff in the refrigerator.
I’m trying to filter through all my sippy cups and discard all the “bad” ones. I’ve found that half of my sippies are #5 with and without straws (mostly chewed up) and the other half don’t even have a recycle number (and these are my most recent purchases, dec 09). What does that mean exactly? Should I be keeping or throwing away the cups without a recycle number? and should I toss the #5’s because they’ve been reused for years?
Just wondering about the effects of using lotions, and soaps out of plastic containers. I reuse plastic soap container marked 1 and refill it for traveling ease. Are the contaminents absorbed into the skin. Lots of lotions, cosmetics, etc. come in plastic containers. And for that matter what about milk? Thanks for your help