Episode 11 – Material matters

Intro (00:00:19:16)

Science on the menu, a podcast by the European Food Safety Authority. 

Ed (00:00:34:08)

Hello and welcome to another episode of Science on the Menu. My name is Ed Bray and I work in EFSA's communications team. And joining me today is Cristina Croera from EFSA’s Food Contact Materials Team. Hi Cristina.  

Cristina (00:00:36:23) 

Hi Ed, thanks for inviting me.  

Ed (00:01:14:07)

Welcome to the podcast. Today, we're going to be talking about food contact materials. Now, if you're listening at home and you're about to have something to eat, a snack while you're listening, the food contact materials could be many things. They could be the plate, for example, that you might eat your snack on. They could be the knife and fork you use to eat it. It could be the packaging that comes with the food, or it could even be the glass that you're about to drink some water from. So, these are just a few examples. There are many. Cristina, can you give us some more examples of food contact materials and where we find them actually in our everyday lives?  

Cristina (00:01:48:09)

Food contact materials, as you said indeed Ed, are materials that can come into contact with food and drinks. And so of course they are in the final products like bottles, reusable bottles, cutlery, dishes, but also in the equipment that is used to produce these final materials or are in containers for water or for coffee machines. These kinds of things, whatever can be in contact with the drinks or food that we are exposed to. 

Ed  (00:02:11:08)

Okay. And yeah, for the food chain to be safe the food needs to be safe. But obviously also all of these materials that come in contact with the food - there needs to be a level of safety as well for the consumer. And this is where EFSA comes in. What are some of the potential risks from the food contact materials for the consumer? 

Cristina  (00:03:01:23)

The risk indeed can come from the fact that some traces of these materials can migrate into the food or into the drinks. So, we have to be sure that this amount is not affecting the health of the consumers. And so, this is why the scientists of EFSA evaluate these substances and provide some safe levels to the legislators of course. A typical safe level that EFSA sets is named Tolerable Daily Intake that is an amount of a substance that can be ingested daily over a lifetime without producing an appreciable risk. So, this is the usual, the standard value that is provided by the evaluation by EFSA. 

Ed (00:03:12:18)

Okay. And are there factors that affect the level, the speed of migration of these substances into food? 

Cristina (00:03:51:15)

Yes. There are some elements that could alter this migration, for instance, the temperature. So, if a material is used not according to the indication given on the label, for instance, this could create a major risk. The use, for instance, in a microwave where it is not foreseen, but also if a container is scratched, for instance, after a long use and the material is not anymore as it was. And this could create also a major release of the compound of the material. 

Ed  (00:03:59:08)

Okay. So, it'd be good idea then for whoever it is to throw that one away and to buy a new one.  

Cristina (00:04:00:05)

Yes, absolutely.  

Ed (00:04:09:04) 

Okay. And once you've set this level, what happens then? How can we ensure that consumers are below that safe level? 

Cristina (00:04:27:20)

This is a matter up to the EU legislators, meaning that they take our Tolerable Daily Intake and they convert it in a specific migration limit. And this in order that the exposure of the consumer is below the TDI that we have set.  

Ed  (00:04:41:19)

And what I find interesting is that there are many different types of food contact material. We could be talking about plastic, which I think is the most common, but there's others. It could be ceramics, it could be glass, even metal I imagine.  

Cristina (00:05:00:04)

Yes, sure, indeed. And plastic is the most common and is also the one maybe more regulated at the level of the European Commission. But there are specific regulations also for the other materials and usually at the level of member states, for instance. 

Ed (00:05:33:08)

So, we've talked a bit about what food contact materials are in general and that there are substances in there that could migrate into the foods and therefore they need to be checked and levels need to be safe for consumers. Let's look at those substances now. One of the most well-known, at least among consumers, is bisphenol A. People know it as BPA. We recently did a new evaluation of the safety of BPA. So first, can you tell us a bit about BPA? Where can we find it? And then we'll move on to the evaluation we did. 

Cristina (00:06:14:05)

Yes, you are right. We have just produced an evaluation, a new evaluation in April this year. And bisphenol A is a substance that is produced together with other materials to produce some plastics, polycarbonate plastic in particular. It is a kind of material - rigid and transparent - that is used to produce reusable bottles, mainly, and containers, but also is used to produce epoxy resins that are in the protective linings of the internal cans and vats. So, this is also a wider use of this material and that affects our daily life. 

Ed (00:06:26:17)

Okay. And what did we conclude then in our evaluation? 

Cristina (00:06:35:24) 

In our evaluation, we have concluded that there is a health effect of this substance for all the age groups of the population.  

Ed (00:06:45:17)

Okay. So, we found this potentially adverse outcome. And then what we do then, we lowered the TDI?  

Cristina (00:07:30:16)

Yes indeed, we lowered the TDI 2000 times compared to the previous one that we set in 2015, that was set, however, on a temporary basis, because already at the time we identified some potential effects of the level of the immune system. But the dataset was a bit weak, was a bit poor, and we knew that something new was coming in the next year. And that's why we evaluated a big quantity of new data that permitted to cover the uncertainty that we found at the time. And we identified this lower level of concern and that's why we reduced the Tolerable Daily Intake so much. 

Ed  (00:08:17:02) 

Okay, so what happens now? What's going to happen next? We know that there's this potential risk from materials that contain BPA. What's going to be done about it? 

Cristina (00:08:07:17)

Now, this opinion that was developed by our experts of course will be discussed at the level of the EU legislators and they will decide what to do, meaning if to ban this substance or to introduce limits of migration even lower than the one that were already set at the time of the previous opinion. So now it's in their hands in order to decide what will be the best solution, the best action in order to protect the consumers. 

Ed (00:08:53:11)

Okay. Well, that's an interesting example of one of the substances in a food contact material. And there are, I imagine, many others that we will assess and similarly come up with outcomes where the legislators will act. I wanted to move on to another area of work in the field of food packaging and food contact materials, and that's related to recycling, because I know that the plastics on the market, they can also be recycled and then used in in food packaging. What does EFSA do in relation to the recycling of packaging? 

Cristina (00:09:59:18) 

Yes, you are right, the recycling of plastics particularly is of much relevance also considering the approach of the EU legislators at the moment with the Green Deal etc. EFSA deals with this of course because there could be an issue using plastic that can be recycled, because it could contain residual levels of a substance that contaminated this material. So, for instance, if bottles were used not for food, but containing other liquids - alcohol, gasoline, whatever - so, it means a misuse of this substance, we have to be sure that no residues of this can remain in the plastic. So, what EFSA does is to assess the process by which the original plastic is converted to a recycled one. And so, this process has to be evaluated as safe by EFSA and then authorized by the European legislators. 

Ed (00:10:09:08)

Okay. So essentially, each process that is used to recycle plastic has got a kind of green light, a safety green light and then an approval. 

Cristina (00:10:25:18) 

Exactly, every process. It's an industrial process which deals with passing these materials through high temperature, high pressure, in order to release all the possible contaminants that can be there. 

Ed (00:10:45:02)

Okay. I find it interesting. I think I see a kind of tension between the environmental goals of increasing recycling, of reuse, etc., a tension between that and possible risks actually from the food safety perspective. Would you agree? 

Cristina (00:10:59:14)

Yes, it's true. It's correct. There should be a right balance. If we recycle, we have to be sure that the process is safe. Otherwise, but this is the case indeed, otherwise the process is not authorized. 

Ed (00:11:06:02) 

Okay, so the first step is always safety. Yes, but with the greater goal of environmental sustainability in mind.  

Cristina (00:11:31:02)

Exactly. So, for sure, we are in this direction already because some replacements have been already put in place using for instance bamboo or wood. So natural material, but plastics still remain one of the safer ones. So, we can go in this direction to find the right balance between the two aspects that you have mentioned. 

Ed (00:11:37:01)

Okay. And presumably all of these replacement materials need to be checked for their safety as well.  

Cristina (00:11:49:09)

Absolutely. Indeed, with plastic, of course, we have lots of data and usually we are very sure about our outcomes. The same we have to do with the possible alternatives. 

And can we talk a bit about some of the future trends also in packaging? I've heard about, for example, active materials, active packaging and intelligent packaging. What are those? 

Cristina (00:13:27:07)

Yes, these are materials quite present, very interesting. They are already in place on the market. And what are they? The active contact materials are the materials that can absorb or release substances in order to improve, for instance, the shelf life of the food or the quality. So, for instance, are oxygen scavengers. So, they act as antioxidants of the food, or they can be anti-microbial, they can be CO2 emitters. So, they change in some way the atmosphere inside the packaging in order to preserve the food. While the intelligent food contact materials act more as indicators of the status of the food. So, they monitor it. They are used as monitors of the status, so for instance the temperature, the PH of the food, the humidity. So they are sensors, they can give us indications on how is the status of the food. So, it's very interesting. These kinds of materials are really interesting because they help us to provide good quality food. In terms of quality, but also for long preservation. 

(00:13:39:04)

Yeah. And presumably reduce food waste as well because, you know, if there's this antioxidant effect, presumably, you know, less food has the potential to go to spoilage. Is that right? 

Cristina (00:13:40:10)

Absolutely. You are right. 

Ed (00:13:47:22)

Okay. That's really interesting. And you said that's something that we see on the market already now. Is that something that we expect to grow in the future? 

Cristina (00:14:09:03)

I expect so because guidelines have been set already some years ago. So, we received some application by the industry in this direction. And so the technology of course is improving. And so I guess we will find new materials always more improving the quality and the shelf life of the food. 

Ed (00:14:23:19)

Okay. So that's something for our consumers listening to look out for in the future. A final question for you, Cristina. I'm interested to know how you find yourself in the food contact materials team at EFSA. What did you do before? 

Cristina (00:15:03:16) 

Thanks for the question. My previous life was in the research of course. And then I passed on the other side at the regulatory level. It's very interesting. But once I started in EFSA, it was not on food contact materials, but was about smoke flavourings that are substances added to food in order to create an aroma. But very soon I moved to food contact materials. I find them very interesting and I'm sure I will meet other challenges in this area in the near future, after this big evaluation of bisphenol A that I was involved with. 

Ed (00:15:20:22)

Thank you very much Cristina for joining us on today's podcast.  

Cristina (00:15:23:16) 

Thank you Ed it was a pleasure for me.  

Ed (00:15:49:01) 

And I hope everyone at home you've enjoyed listening to it. Please do subscribe to our podcast on your favourite channel and look out for us also on social media where you will find us posting and putting out information on our podcast. But that's all we have time for today. Thanks for listening and hope to join you again next time.