Environmental Impact and Final Verdict

Hello, I'm Greg Foot and welcome to Slliced Bread, the show that investigates the Wonder productucts promising to make you happier, healthier or greener. Each episode, we follow the crumbs of evidence to find out if one of your suggested Wonder products is indeed the best thing since Sliced Bread or marketing BS So today's suggestion comes from Joe Tatasol from Leeds. Hello Joe Hello, Greg. Tell us the wonder product that you would like us to investigate today and why, Joe Today, Greg, I would like you to investigate plastic food storage containers I want to know more about the risks from chemical leaching and from ingesting microplastics that might be associated with then I don't want to discuss if there's any alternates that we should be looking at. Are you more interested in reusable containers here rather than single use takeaway or ready meal containers? So something you might put your leftovers in, keep them in the fridge, pop them the microwave, that sort of thing I'm interested in both. I quite commonly reuse takeaway tubs But predominantly, my interest is in the ones that you buy from the shop with the express intent of reusing it every day state launched work orr you're holding me one up there and that looks red So I wanted to bring you a couple of examples and the first one is a branded Semer software And this is obviously out of hard life. It's been through the dishrasher. It's been nuked in the microwave on countless occasions and it is now a lovely shade of sunset Was that spaghetti bolognes in there? It's all sorts in it. But you can see around the edge there's quite a lot of bubblel in and. it's all rough. I see that on the plastic containers that I use as well. It gets all rough, almost turns white. Exactly. Okay. And what alternatives have you seen? I' found on Ali Express, can I say AliExpress? Yeah, absolutely. AlExpress being a global online marketplace. I' found on AliExpress that you can get extremely cheap plastic containers, which in the pictures looked like they would be comparable quality to the branded ones. So I pulled the trigger, bought a bunch of these, and when they arrived, they're thin, flimsy plastic. The lid doesn't quite fit. But after six months of exactly the same treatment that the branded one had, it's not stained at all. There's no bubbling. Interesting. Barely a scratch on it But what I did notice is on the bottom, there's no markings. There's no CE markings. So I was wondering, does that mean it's made of a different type of plastic that makes it better for storing food but worse for human health? Or should I just stop worrying about it and buy some more? brilliant bunch of questions Interesting fact for you, Joe, The original food storage brand Tupperware was invented in nineteen forty six by American chemist Earl Tupper So it's Mr. Tupper's where Right. Is that really out I mean it's a school day? Yeah So for you, we're going to focus on plastic food containers, Joe. But I want to broaden it a little bit. Listener and email us in to sighted. red at bbc. co. Uk to ask us about microwavable silicon food containers Listen to Sarah emailed in about silicon and metal. She writes, My friend has a stainless steel lunchbox with a silicon insert. Are they less damaging to the environment So let's discuss all of those materials later as well. We've also had a bunch of voice notes in on this as well to our WhatsApp number zero seven five four three three zero six eight zero seven, including this one from listener Jennifer in Perth I am currently inundated with adverts and promotions for what the sellers describe as non toxic food storage solutions That would imply that some are not non toxic, i. e Dog sick Would you have a look into what is the safest and most sustainable way T store fit Thank you Thanks Jennifer, we sure will. two experts joining us today. I can see them on the screens in the studio. They can hardly contain themselves, Joe They're so ready to pack in as much as possible, Joe. Greg enough for the puns, I think you should put a lid on it. But I've been storing them up for you I stop. Yes I'll stop, stop stop Our first expert is a toxicologist at Imperial College, London, who also leads the microplastics team at the Medical Research Council's Center for Environment and Health. Dr. Stephanie Wrightes. Welcome, Steph Hi Greg. And on the screen alongside Stephanie is the managing director and Chief scientific Officer at the nonprofit organization The Food Packaging Forum based out in Switzerland. Dr. Jane Munker. Hello, Jane. Hello, everyone. Well, let's start with plastics then, because that's what you are asking about, Joe. It's easily the cheapest material that you can go for to store or to microwave food. What did you pay for your containers on Ali Express, Joe One pound eighty nine per container Yeah, in a supermarket, they often tend to be a few quid more than that though. Jane, what plastics are these food storage containers normally made from? Wow, that's anyone's guess to be honest, because there's no legal requirement to label What type of polymer is used to make them But sort of typical materials that are used are, for example, polypropylene Plystyne, polyethylene, terphylate and so on. Sometimes on the bottom of the container there's a number. Is that the type of plastic Exactly, those are the so called recycling codes But there's no mandatory requirement to put those on a container. As you say, Joe, they're not on the bottom of your Ali Express ones. No. But if you want to know exactly what the material is, you have to take it to the lab and measure it Next on the list, silicon As Listenna Sarah mentioned, lots of the non plastic containers have a silicon seal But as listener Anne pointed out, there are some fully silicon containers. Jane, our listener Sarah asked if silicon is just another type of plastic It's actually quite different. pllastic is made from dead algae When they die, they sink to the bottom of the ocean. And this happened hundreds of millions of years ago. They turn into what we today call fossil oil. Fossil oil, mineral oils, are the source to make plastics. Now when you turn to silices, the source for silices in general is sand But in order to turn them into materials that become useful, you put a lot of additives into them. And those are some of the same additives that are used to make plastics. Okay, so there are similarities. They're both polymers, which means they're made of long chains of kind of smaller repeating units. pllastics building block comes from fossil fuels, crude oil essentially, whereas silicon's units are derived from silica, sand I said Jung H. ono the next material glass buy glass food containers from brands like Pyrex or Lock and Lock They tend to be a bit more expensive again than silicon. For example, a ner point eight liter Pyrex glass container will cost you around twelve pounds in Argos Janie said there are lots of different types of plastic. There are lots of different types of glass Not lots. Glass is by comparison, a much simpler material. It's also made from sand two major types of glass. O is Soda lime. glass and the other one is Boris silicate glass. Yes. I've seen that a lot. Yeah And so the sodaim is sort of used for glass packaging, like your milk bottles. and the bilicate glass is more used for glass ovenware, for example, things that need to be very heat resistant. So you can actually drop it. They' so hard. Don't try this at home. Interestingly, glass containers often come with plastic lids, but some come with a glass lid. One feature we saw in a couple of the glass containers is that they advertise they can go in ovens up to four hundred degrees Celsius So Jane, I assume if you put a plastic or a silicone container anywhere near that temperature it's going be game over, isn't it? Oh, it's gonna to smell horrible. So that is a benefit. That is a potential benefit there. The final material to tick off the list is one that can also go in the oven metal brand elephant box does a one liter steel box with a glass lid They say the body is crafted from premium three hundred four grade stainless steel. It's significantly more expensive twenty seven pounds It feels quite retro Joe to go metal L we're going back to kind of vintage army mest tins. Yeah, you don't really see it that often. although I did once find someone at work putting one of those in the microwave and I was expecting sparks and thinking that it was going to burn the building down, but it just worked. And then he said something scientific about why that specific metal did work in the microwave. But unfortunately, I can't remember it so I can't tell you. I've got here right herear me.. Interestingly, they say that the steel base is microwave safe. They say that the smooth rounded edges help distribute electromagnetic waves evenly, avoiding the sharp edges that can cause sparking. Jane, I'm the same as Joe here,. I thought, you know, you shouldn't put metal in the microwave full stop You shouldn't put metal in the microwave, but there are always exemptions to the rule. and these products have been on the market for. twoo three years now, I have one of them myself and it really does work. They don't create the sparking in the microwave. What I don't know is what it looks like if you've used it for a while and you get some scratches that happen inevitably, then you may have a problem. So that's still an ongoing experiment for me. Interesting. And just to note, they say only the base is microwave safe, not the glass lid And if you don't want to spend twenty seven pounds, you can get cheaper metal containers. IKEA sell a stainless steel one liter leak proof container for seven quQid. Let's just spend a second on that term leak proof Not all of these containers are leak proof. It's something that we tend to discover at our peril, isn't it Jo It is. and in fact, Going back to the cheap Alot Express unit with the ill fitting lids. bothoth of these live inside a plastic sandwich bag when they go to work with me. Very sensible. This is often where a silicon seal comes in handy, so these products say, as well as leak proof, some also reference being airtight. Steph Does an airtight container keep food fresher for longer Yeah, I mean, I think it keeps food fresher. in theory, it minimises oxidation of whatever's in there. That is enough on the materials, I think, and a couple of the features that these food containers offer. Let's move on to your main question area, Joe, which is around the safety of these plastic containers. Jane, if we store our food in plastic containers Can some of the chemicals from the plastic get into our food Yes Very generally speaking, it will be small molecules. Plastics are made up of these big, big polymer burnes are huge gigantic molecules and that's not going to move, right? But the small molecules that are present in plassic, they can leach out. And there's a few principles when migration will happen The first one really is temperature. So at high temperature this migration will speed up and it will happen at much, much higher levels. But storage time plays a role and the acidity and the fat content of your food stuff that you're store in also has a huge impact on what chemicals will be ending up in the migration mix Joe does it worry you hearing that small molecules can leach out of plastic. You don't like to think of it D. you don't like to think that there's some unknown chemical getting into your food But I suppose you have to take a wider view and We need to know if that is actually having a tangible effect on our health.? Is it something that is quantifiable? Is it something that is comparable to the other choices we make day to day Is there a way that we can tell, Jane, if this migration this leeaching is happening in our containers at home Wellile leaching happens or migration, as we call it happens when you have non inert materials. And one way to determine whether your material is not very inert is to put a strongly colored foodstuff or juice into it like beetroot juice, for example, or curry or a tomato sauce or something like that. And if you remove the food from the container, but you still see residual color in the container even after washing, you know that the plastic has absorbed some of those pigments from the food. And that will show you very clearly that it is not an inert material. Well, I think we can tell from the color there, Joe, your plastic container is not inert. Yes, I think we can definitely say that for certain Well it just shows you that there's a chemical interaction happening because this migration, this leaching out of chemicals is not a one way street. If a material like Doe's plastic container can absorb can leach out. Almost all the plastics that we looked at made a point of saying they are BPA free Jane, what is BPA please BPA is a chemical that's been used to make plastic since the nineteen fifties It turned out in the early nineteen nineties that this chemical leaches out of plastics And that BPA is a so called endocrine disrupting chemical. so it interferes with the hormone system and it mimics the female hormone estrogen And that's not something you want have in food And it's recently been banned in the European Union, and the UK is following suit on that But it's still being found in food. it's still being found to migrate. especially out of recycled plastics, for example. And some containers say BPA free Because BPA has such great functionality, the industry has replaced it with chemicals that are very similar in their structure to BPA. So for example, bastphenyl S or bphenl F or bphenyl M, you get the message here. They're all bastphenyols. So you can say it's BPA free, but you have something else that has similar similar toxicity as well. So Joe, the suggestion there is a plastic maybe BPA free, but it could be an alternative BPA Yeah, yeah. So within the EU, is it fair to assume that any chemicals it's been replaced with have been tested proven to be safe Unfortunately not, I wish that were the case, but it's not. It's very, very frustrating and Bistral A is Just one of these notorious examples because it's been on the market for such a long time. the regulation is limping behind woefully here. So it's not a great story I mean, yes, you'd hope that there would be regulation and enforcement of anything that's coming into contact with your food. You're saying, Jane, it's a bit of a whack a mole situation. Is it? newew things has appeared? takes time for the regulation enforcement to come into play during which time there may have been an impact Yes, there's over fifteen thousand food contact chemicals that are known, and experts estimate that there could be up to one hundred thousand chemicals that are migrating from these different food contact materials into food So just imagine how much work you have to do to fully evaluate these. With BPA it took over thirty years We need to do so much more and there's so many more chemicals like bphinyl A out there that need to be removed Hello, it's Future Greg here. Just a note to say that after recording, we put some of Jane's comments about leaching and the regulation and enforcement of plastics to the British pllastics Federation. They're the trrade Association for the UK's plastic indndustry. Here is our producer Simon with their response Yes, Greg, now on chemical migration or leaching. They say all food contact materials, including plastics, glass, metals, and paper, can involve some degree of substance migration under certain conditions, but that modern food safety regulations are designed to assess and control this migration to make sure that any exposure is within established safety limits and isn't a risk to human health. On the staining we've been talking about in particular Joe's container, they say that visible staining or absorption of food pigments is not in itself evidence of harmful chemical migration or a risk to human health. And they do add that the advice around damaged food containers with those scratches or bumps is that they should be replaced as part of general maintenance practices Just a word on BPA. Now they do confirm that the UK Food Stards aggency are looking to implement that ban on the use of BPA. But interestingly, they added that there has been a focus to ban similarly related chemicals like the ones Jane talked about bisphenol F and bisphenl S, so as to avoid substitutions or as we put it, those whack a moole situations in future Thanks, Simon. Okay, back to the episode. microplastics We've talked about these a number of times on previous sliced breads, mostost recently in our episode on chopping boards Microplastics aren't specific chemicals. They're tiny bits of plastic that might contain those specific chemicals, of course, but they're also small enough to be a concern in and of themselves. As I mentioned in your introduction, Steph, you're leading the microplastics team at the Medical Research Council Center for Environment and Health. Are microplastics being released from plastic food containers into our lunch? And if so, how if you go on the published data, then yes, there are microplastics being released from these food containers and similarly they are released foollowing degradation that Jane mentioned with respect to chemicals. so various heat cycles, freezing, sunlight exposure, all of these things can contribute to hammer is seemingly relief However, I think I do have to caveat this with the fact that Analytically, measuring microplastics is still quite challenging. and we're still at a very early stage and are really just sort of becoming aware of the growing limitations in how we measure and analyze microplastic. Okay, so we can't necessarily put a figure on the number of microplastics that being released. But microplastics are being released. you said with heat, with sunlight, I presume when you just rub your spoon against the container, I was was going say I think also a mainw is more on the mechanical abrasion side, Whher we're using abrasives when we're washing and cleaning and growough there's abrasives, you know in the dishwasher cycle, that rooughs the surface and then will probably make it more susceptible to some kind of breakown. If we swallow microplastics How far do they get into our bodies? Do they make it through the stomach to any get into our bloodstream This is a really great question. I mean, we have evolved, you know for our evolutionary history to keep particles out of the body and not just particles but pathogens and you know, foreign material So our gut has quite a few defences. We do have a mucus barrier lining the gut. And then we have our cell wall or our epithelium. And again, that's quite a tight barrier as it'site generally quite hard for things to penetrate it So when we're talking about microplastic, it's actually Theoretically it should be quite unlikely for microplastics to absorb across the gut I'm not saying it's impossible. It's just unlikely, I guess, is the message Okay, well, that's to hear. Jane, are you worried about microplastics The larger bits of microplastics, the ones which we actually are able to measure with good reliability right now Those aren't really the ones that I'm very worried about. I'm worried about The nanoplastics as we call them, that are much, much smaller, which are much more difficult to measure releliably right now And because of their small size, the probability that they will actually go through cell walls is very high. And we do see that at least in lab studies and in animal studies, they are doing that. They are being ingested and taken up by the body. I also just wanted to add that healthy guts differ from GI tracks where there are leaky gut conditions So if you suffer from something like that, the probability that you will take up these particles is increased a little bit. What is the actual impact of getting microplastics as we discussed into the blood or into different organs or being absorbed by the gut? How does that affect one's health Is it likely to not lethal or is it is it going to cause certain conditions or how does that work We do see that there can be a toxic effect linked to plastics. I think generally this is probably a bit more related to the fact that it's challenging our immune system so our body wants to try and get rid of it and fight it in the way it would any foreign material So it can lead to inflammation, potentially some tissue level damage. but as with anything, it's very much dose dependent. So we're talking about very high levels. And I think the point that Jan made, the smaller the particle, the greater the likelihood for absorption. So the big question is where is that ending up? And is that building up to these levels that could then be considered harmful? There are a few studies that have linked the presence of plastic from arteries in your neck to an increased risk of stroke or an increased cardiovascular outcome and even increaseed mortality. But there's also these challenges that come with measuring microplastic and so actually whether it was plastic detected at all, it is still unclear and needs more research. Yeah. so it sounds like in the domestic setting There's no real sort of evidence to say that we are in danger from exposing ourselves to the levels that we would see on a day to day basis. I think right now, I wouldn't say there's a risk of something acute or happening that's very bad in the short term. The other point is that we do know that particle exposure is bad, right? We regulate air pollution based on just particles in the air. Th we know that too many particles are bad So I guess from that respect, minimizing exposure to micropllastic would only be of benefit. But absolutely, right now I don't think It's killing us, but I think There's also a lot we don't know, so it's hard to say Okay, let's return to some of the factors that we've heard might increase the amount of leaching Microwaving firstirst, Joe, you said that you put your food in these passic containers, you microwave them Steh, all the plastic ones we looked at said that they are microwave safe. I don't microwave in plastic and it's not just because of the particulate release. it's probably more driven by the potential for chemical release. So I definitely do say I think there is a concern and I would personally avoid microwving plastic I think what we have to do is reclaim the word safe. you know To me, the word safe means there's no leaching of hazardous chemicals and there's no leaching of untested chemicals, but that's not what The label microwave safe means. It means it complies with regulations. and that's something unfortunately very different than no leaching of hazardous chemicals What about freezing? Because similarly, all of the plastic containers we looked at said they were freezer safe. considering what we've just heard about microwaves safe shouldhould we be skeptical here? at those lower temperatures Chemical transfers will be less likely. However, when it comes to particle abrasion, that may be a different story. I think freezing as well, you know, the kind of freezing em brles, plastic materials, potentially to surface micro kind of fracturing and cracks, which again, could release some particles might increase the amount of microplastics Let me just add a third type of kitchen appliance to the mix. These plastic containers also often say they are dishwasher safe, although some clarify in their marketing information that you should use the top rack. Jane, given what we've heard about the effects of heat abrasion on plastic. Do you think it's better to avoid putting these containers in the dishwasher at all Or will it be fine if say dishwasher safe I would not put plastic in the dishwasher full stop You know, dishwasher detergent, it's quite aggressive chemistry It can degrade the plastic And the heat will also lead to degradation and it just will speed up the aging of the plastic. And aged plastic leaches more and more chemicals and more and it generates more and more microplastic. Would we say that it's the dishwasher or the microwave that's causing this kind of fury the bob abrasion? Yeah, the kind of white raised rough bits? And should we be throwing these tubs away when that starts to happen I would definitely throw it away here. And why has that not happened on the cheap Ali Express tub which has had a similarly hard life. What worries me about that one is that there's not this food grade safe symbol on it, right? So I mean that could be that could rilli it also to contain other chemistries that are definitely not approved even for food safety. You know these online vendors, they produce outside of Europe, they import into Europe, There's not many checks being done on the stuff that gets imported. I would be very careful with buying those kinds of products. Future Greg here again, just to say we also put these comments to the British Plastics Federation, and here is prodroducer Simon again with their response. Now they say when plastics are designed for heating, such as in a microwave, they undergo testing under realistic and worst case conditions, and that guarantees any potential chemical migration remains well below the strict regulatory safety limits. They go on to say reusable food grade plastic containers are specifically tested for their intended uses, and that includes microwaving, freezing, and dishwashing. And again, any containers that become excessively worn or damaged over time should be replaced. Thanks, Simon. backack to our original chat in the studio Well, let's park plastic for now. let's discuss some of the other materials. Silicon containers Jane, some make a point of saying that they are non toxic Does that mean that they're safer than the plastics? Non toxic or safe, if you don't define what you mean with that, it can mean anything, right? When it comes to leaching of chemicals, it actually behaves very similar to plastics. Could it be best to go for a metal container? then we saw elephant Box say that their metal containers are one hundred percent plastic free with no toxins and chemicals Yeah, I would definitely prefer materials that are inert. So that means they don't leach chemicals, but they're also not absorbing chemicals. Glass is inert. soes The glass containers we looked at claim that they're stain resistant Some such as the cube from Lockanx say that they resist odors. Exactly, that's the same because oders are also in that sense, chamacs. What about if the container is glass but the lid is plastic Yeah, I use those quite a bit as well at home just because they're practical. I think it's okay. you know when I have hot food, wait until the food's kind of cooled off before I put the lid on and then I'm storing it in the fridge. You have less surface area in contact with the food like that. And I guess the area that you can cause abrasion to with your spoon or your fork or whatever iss going to be glass. Yeah Glass Yeah You don't care about that abrasion. But you could still be getting transfer of microplastics, you could still be getting leaching from the plastic lid. So would you prefer something that's all glass or all metal Yes, I think the reality is there are no perfect products, right? So I prefer less plastic, but I also don't want my container to leak when I'm transporting it around. So it's a shout out to all the innovators out there. Give us a material that is inert and doesn't leak hazardous chemicals Before we try to pull all of this together for the SBBS final question, I just want to finish the answer for Jennifer from Perth She asked us about what is the safest way to store food and we've explored that Shell also ask us what's the most sustainable way to So I want to welcome in our researcher Phil Sansom to summarize his research on this. Hessel. Hi, Greg hi We've talked about how some of these containers can release microplastics and chemicals, and those can go into the environment, as well as potentially into our bodies. So there's a clear environmental impact there. But if we zoom out, Phil, what do the stats say about the impacts of these materials across their full life cycle Yeah it's a good question. To find out we spoke to Dr. Alejandro Galago Schmid, who is the lead author of a lifecyycle assessment from twenty eighteen of exactly this. He told us that if you compare plastic to glass containers Glass actually has bigger impacts on the environment than plastic in every way because produced in the glass containers takes more raw materials and energy he calculated the impacts across a range of different factors and he figured out that to make the impact equal for plastic and glass you'd have to use the glass container Potentially more than three times as much as the plastic one, depending on what environmental impact you're talking about Joe, didid you expect that? The reason I thought they might be worse for the environment is purely because they break and you have to replace them more often. With glass, yeah, if it breaks, of course, you're done. but if you look after it carefully, you can keep it for a long, long time. I've had some of these containers for decades now So canan we not recycle plastic after we've use them once it's stained, not is it not useful? is that the concern So because when you recycle plastics, you will see get high levels of hazardous chemicals in recycled plastics. So actually I'm pretty concerned about this push you know for using more recycled plastic, especially in food packaging. I don't think that's going in the right direction What else does the research that you read suggest for ways to reduce the environmental impacts from our food containers interesting result that Alejandro and his colleagues found from their papers is that the use of the containers made a big impact the way that you wash them and clean them And he told us that the best way to reduce your environmental impact is if you're hand washing, just use less water soap and heat. I know it sounds basic, but apparently it makes a big difference. Thanks for Okay, experts, time for the final question. Now as is often the case, I don't think this is arere foods containers the best thing since Lice Bread or Marketing BS. I think it's more of a question of which foods container material and design, if you like is the most sliced bread Def, what would you say Oh Well, I can tell you what I have at home. I have a glass container with a silicon ledge And I also have a stainless steel container over a silicon midge. I just use plates in the microwave lids Great tip Jane, what about yourself? Which material would you go for? So what I love about glass is that when I open the fridge I can actually see what's in the containers. With stainless steel, you always have to open the lid, but I have both at home. So I think both of them are great. When I'm on the go, when I'm taking food to the office, for example, I usually pop it in a stainless steel container just because it's a bit lighter But yeah, I definitely try to reduce plastics in contact with food Joe Hello. The final word goes to you. What will you be storing your lunches in in the future? Well, in my specific situation where I batch cook three weeks in advance and thereforell need fifteen of these to fit in the freezer. Oh. I know, I know. I don't know if I can make the cost of glass or steel ones makes sense. So I'm probably going to stick with the plastic and be the test dummy So I respect that. As Steph said, when you heat it, put it on a plate. and I would even say when you batching, wait until the food has cooled off f put the food hot into the plastic containers, you'll do yourself a favour if you don't do that That is a very good tip. Thank you. And it certainly I will look into the glass containers and if I can find some small enough and cheap enough, then I will be switching to them for sure And with that I shall wrap up this episode and this series of Sliced Bread. A big thank you to Joe, Steph, and Jane for joining me. We're going to take a short break to cook up another batch of investigations and store them in our tupperware or glass or steel. While sliced Bread is away, we'll be serving up another series of toast, where Sean takes a look at the big ideas that promised so much but ended up See y This episode of Sliced Bread was researched by Phil Sansom and produced by Simon Hoban and me, Greg Foot. Our studio managers were Kelly Young and Ben Cuthbertsson. Sliced Bread is an audio North production for BBC Radio four If you've got a scrolling problem, then this is the podcast for you. It's called Top Comment with me Matt She. And me, Mariana Spring, We both investigate social media for a living. Whether it's disinformation, conspiracy theories, internet culture, memes. We're going to be getting behind the stuff that is popping up on your feed on this podcast That's top comment on BBC sounds