Episode 12 – Toxic tastings: contaminants in food

Intro (00:00:10:02)  

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

James (00:00:20:04) 

Hello, everybody, and welcome to another episode of EFSA’s podcast series, Science on the Menu. My name is James Ramsay. I'm the Head of Communications here at EFSA. And today we're going to be talking about contaminants in food. To do that and to join me in the studio, we have Mary Gilsenan, and Mary is the Head of our unit for Feed and Contaminants. A very warm welcome to you, Mary. How are you? 

Mary (00:00:47:05) 

Thank you, James. I'm good, thank you.  

James (00:00:48:13) 

Great. Let's start with the basics. So, what do we mean when we're talking about contaminants in food? Could you just give us a bit of context to help us understand?  

Mary (00:00:59:19)  

Okay. So, I mean, there are different types of food contaminants. We have the classic ones, like microbial contaminants. When we eat salmonella or listeria, for example, and we get sick the next day...we know all about those. They're microbial contaminants. But what we're going to talk about today is more on chemical contaminants. And these are a whole vast array of chemicals substances that are present in our food supply, unintentionally present. They're not deliberately added, like pesticides, for example. They're unintentionally present for different reasons and generally present at low doses. But if we consume them over a long period, they could have harmful effects on health.  

James (00:02:00:12) 

Okay. So, you mentioned they're not intentionally added. How might they enter the food supply then? What are the different kinds of routes for contaminants to come into our food?  

Mary (00:02:11:15) 

I mean, they can be present in food through different routes. 

So, we have naturally occurring chemical contaminants. And they enter the food chain naturally, usually through plant-based foods.  

James (00:02:33:24) 

So, what would be an example of that?  

Mary (00:02:36:22)  

A typical example would be mycotoxins: toxins that are produced from moulds that form on plants either in the field or post-harvest. And there are many, many types of different micro toxins in the food supply produced from different types of moulds. And even though they're natural...We sometimes think “natural” with a good connotation. But natural is not always good. They can be quite harmful. And then we have processed contaminants which occur during processing or cooking and they kind of form naturally during the processing and cooking. But they can have harmful effects as well, if consumed in large amounts. The other type of contaminants that we assess the safety of are environmental contaminants. And these are things like dioxins, PCBs, brominated flame retardants that are emitted into the environment and air, water, soil, for example, and end up in the food chain. 

James (00:03:58:01) 

Okay. Am I right in thinking these are sometimes referred to as the ”Forever chemicals”? 

Mary (00:04:04:02) 

Indeed, yes. Because they're so persistent in the food chain.  

James (00:04:07:10) 

One class of chemicals that falls under the umbrella, I think, is PFAS. We've seen a lot of coverage in the media recently about that and we've done some work on PFAS in the past and our colleagues at the European Chemicals Agency are also working on that. And in fact, before we sat down today, we took a moment to speak with them to tell us about what they're doing in this area. So, we'll hear what they have to say and then we'll come back to our conversation here.  

Bastian Zeiger (00:04:42:01) 

Why, PFAS are a problem? I am Bastian Zeiger. I work at the European Chemicals Agency or ECHA. PFAS are very persistent and even if their release would stop today, exposure would continue for many decades or even centuries. They contaminate, for example, groundwater, but also drinking water. And they are very, very difficult to clean up. This means that they accumulate in the environment up to a point where they will cause an effect. This is especially an issue because they're used in so many different applications. 

To give you a few examples, they are used in food contact materials like in frying pans, they’re used in textiles, like in the waterproof jacket that you put on when it's raining outside, but also in a host of different industrial applications. This also means that daily exposure leads to presence in our blood. And in fact, most of us have them in our blood today. 

Now, let's talk about the proposal that has been submitted to ECHA. It was submitted at the beginning of this year by Denmark, Germany, the Netherlands, Norway, and Sweden. And it covers all PFAS and all uses of PFAS. There was a six-month consultation which ended on the 25th of September, and we received a record 5600 comments from over 50 countries. They were submitted mostly by companies but also by sector associations, NGOs, individuals and so on. You can access all non-confidential comments on our website. The Risk Assessment Committee and the Socio-Economic Analysis Committee are currently evaluating the proposal that we have received. RAC, the Risk Assessment Committee, is looking at the PFAS’ risks. SEAC, the Socio-Economic Analysis Committee, is evaluating the costs and benefits of the proposed restriction. We are very committed to deliver a final opinion as soon as possible, while at the same time ensuring that there is proper scrutiny by the scientific committees. Once the opinion has been adopted by both RAC and SEAC, it will be published on our website and the Commission, together with the EU countries, will decide on the final restriction.  

James (00:07:04:10) 

That's what we're kind of looking out for, I guess, at EFSA. What do we do? I mean, what does a risk assessment of contaminants in food or chemical contaminants in food involve? And how would we go about, you know, looking at these chemicals?  

Mary (00:07:22:07) 

Well, typically we get a request from the risk managers in Brussels, the legislators in Brussels, to look at a particular contaminant or class of contaminants. And we work with a team of experts from all over Europe with all different disciplines. So, we cover all areas that need to be covered. And our experts would typically assess the toxicology literature and look at all the possible toxic effects that a particular contaminant could cause for humans or animals, depending on what literature is available. We would also estimate the dietary intake of a particular contaminant in food.  

James (00:08:11:10) 

Okay, this takes you back to your PhD.  

Mary (00:08:12:21)  

That's my background, indeed. And we have a team of experts here in-house and EFSA doing that. And we have very, very good data collected in EFSA to do that, that we get from different European countries. And we essentially, our experts look at the toxic effects. They agree on the most sensitive toxic effects. And then they estimate the level, the highest dose of a contaminant that does not produce an adverse effect in animals, for example. And then they would apply a safety factor to that and try to estimate a tolerable daily intake, a safe intake for humans. And then, of course, we compare that to the estimated dietary intake, and they assess the risk based on the intake and the toxicological effect.  

James (00:09:17:06) 

That makes sense. If the exposure is above that level, let's say the safe level, the tolerable daily intake, then there's a risk...that implies a risk. 

Mary (00:09:31:21) 

That implies a risk.  

James (00:09:33:22)  

So that describes the risk assessment that we do, we then provide that advice, then we go back to the so-called risk managers. So, in this case it's the European Commission or the Member States, and they can then decide on actions to take, you know, in the European Union. 

Mary (00:09:54:16) 

Exactly. In Brussels, they typically legislate based on our scientific assessments. And that could be putting in place maximum levels of contaminants in food or feed, by the way, because some come in through animal feed into the animals and then humans. Or they might set recommendations for closer monitoring of particular contaminants in Member States and ask the Member States to send those data to EFSA every year. So they keep an eye on the situation basically in the Member States. 

James (00:10:34:08)  

Very good. You've given us a sense merits of what EFSA does, and you know, the different types of chemical contaminants that we're looking at. I just wanted to go back to something you were saying about the process contaminants. Because it strikes me that, you know, we may as consumers be familiar with some of these contaminants somewhere in the environment, okay. Where, as an individual, you know, there's not a lot you can do to impact on your exposure to these to these substances. But with some of these processed contaminants, there is something that, you know, me as a consumer in my own home can do. Can you just talk a bit to us about that and maybe give us a specific example? 

Mary (00:11:20:21)  

That's true. I think the processed contaminants are the ones that are closest to our kitchen. And the one that most people know about, of course, is acrylamide, because it forms during high temperature cooking. Also, in the kitchen as well as in the food factory. But that's one where, you know, we as consumers do have a little bit of autonomy in controlling the level of acrylamide that we consume.

James (00:11:55:04) 

So how would I recognize acrylamide in the kitchen then? Whatdoes it look like?  

Mary (00:11:59:22) 

Well, you know, when you bake or fry chips, for example, the nice brown colour on the chips or when you bake a cake, the nice browning on the top. And yes, it's typically that nice brown colour that we have on baked and fried food. And it also gives us a nice taste as well. And also, when we toast, if we overdo it a little bit, it's perhaps not good on the acrylamide index.  

James (00:12:32:02) 

Okay. And what's the risk from acrylamide. I mean, if I remember correctly, it's linked to the carcinogenic effects. It's a cancerous effect. 

Mary (00:12:41:04) 

Yes, it is.  

James (00:12:43:01) 

So that's an example where we as consumers, I guess, can do something ourselves to try and reduce our exposure to our intake of these chemicals. 

Mary (00:12:52:14) 

Exactly.  

James (00:12:53:15)  

And what would that mean? How do you go about doing that?  

Mary (00:12:56:12) 

Well, if you like to cook, if you like potato chips and you like to cook them in the deep fry fryer, for example, You know, it might be good if you want to reduce your acrylamide, to reduce your intake of the fried chips in the deep fry fryer, which can also be a win-win situation because if you want to look at your waistline as well, it's a good thing, to cut down on those type of foods. 

James (00:13:20:03) 

Okay. A double win, double benefit. Okay, Mary, thanks very much. Well, we've talked to you today about, you know, what EFSA is doing in this space, what different types of chemical contaminants we find in food...Before we close, I just wanted to ask you, you know, to look forward a little bit and to ask you, for your thoughts on what the future holds for the assessment or the risk assessment of chemical contaminants. 

Mary (00:13:50:10) 

Yeah, it's a good question. I mean, probably climate change is a big factor that will influence the levels and the distribution of chemical contaminants in our food. And here I go back to what I was talking about previously about mycotoxins and natural, they are naturally occurring contaminants. Because you know, as the climate changes and Europe gets hotter, these types of changes have a direct impact on the formation of moulds and crops, for example, and they can induce even other mycotoxins that we've not looked at yet, for example, or even that can change the veracity of existing mycotoxins. So, I think this is probably one of the key factors that will influence is the level of contaminants in our food chain in the future. 

James (00:14:59:10) 

Okay. And is that something that EFSA is kind of working on already? 

Mary (00:15:03:04) 

Absolutely. We have done several scientific opinions on mycotoxins in particular, and it's probably one of the most common type of requests that we get from the legislators in Brussels in these years and apart from doing scientific assessments, we’re also working with universities in Member States to try to understand more how mycotoxins are formed in the environment and the impact of climate change on mycotoxins and food.   

James (00:15:35:05) 

Okay, Mary, thanks. Before we let you go, one last question. Do you have any advice, anything you'd like to share with our listeners on the subject of contaminants in food? 

Mary (00:15:49:05) 

I would like to reassure everybody that here in Europe we have a very strict, regulated food safety system to make sure that contaminants are highly regulated and that our health is protected. I'd also like to encourage everybody to enjoy food and continue to use a balanced and healthy diet. And one of my personal tips that maybe I can share is whenever the toaster overdoes the toast, I always scrape the black off before I eat it. To get rid of the acrylamide and furan. 

James (00:16:30:31) 

Very good. Okay. Thanks a lot, Mary. That's brilliant. Good note to end on. Thank you very much for your time. It's been a real pleasure to speak with you today and to get your insights and expertise. To our listeners: If you'd like more information on contaminants in food and a whole host of other subjects, then do check out our website. We will be back again soon with the next episode of Science on the Menu. So please stay tuned.