Dr. Barouki, or how I learned to start worrying about the Exposome and love hard science
Three Young Gasteiners (Francesco Florindi, Vladimir S. Gordeev and Dimitra Panteli) talked to Robert Barouki, following his presentation during the one of the environmental health sessions of the European Health Forum Gastein 2017 (Forum 9, Environment & Health: “Building the evidence base for policy”, Part 2 – The Future). Dr. Barouki is the Head of the Toxicology, Pharmacology and Cellular Signaling Unit at the French National Institute of Health and Medical Research (Inserm) and a Professor of Biochemistry and Molecular Biology at the Université Paris Descartes.
YG: Exposome…If you wanted to explain it very simply, to someone who has no previous knowledge at all, how would you do that?
RB: The definition is, in fact, quite simple: it’s the totality of exposures that we encounter over our lifetime that can influence our well-being and health. And what we mean by “exposure” is diverse: it’s exposure to chemicals, physical elements like radiation, for example, or biologics. But it’s also exposure to societal, economic or psychological factors – for instance, if you have grown up in poverty, or in a family with many problems, that’s also an exposure. So, you have to take exposure in a wide sense, and [the exposome] is the totality and combination of these exposures over your entire lifetime. Also, as we know now from a number of studies, that even that what happens to you during your fetal life, in utero, can influence your overall well-being and health. There are, of course, many more studies going on examining the correlation of these parameters… it’s a very exciting field of research!
YG: And in terms of political attention (and funding), who’s winning, the genome or the exposome?
RB: The genome has already won a lot! I think maybe now it’s time for the exposure and the exposome to get more attention, because that’s where we lack the evidence. We need more research because there are many uncertainties around this issue. And the policy makers like the concept! For example, we convinced the French government to put the word “exposome” in the introduction of the Health Policy for the next five years. They found it very relevant and “sexy” to start with it, meaning that, currently, the French health policy will be inspired by the exposome concept. Still, it is important to explain it well [to policy makers]. You can listen to the radio, and someone will tell you that you should eat fish, because there are many good nutrients in fish, like good lipids. And then someone else will tell you dioxin and mercury are extremely bad. Where do you find dioxin and mercury? In fish! You have to have a full view, the pros and the cons of eating fish. You have some pros nutritionally and some cons toxicologically, and you have to balance the two. So, you can eat salmon, but not that often, and maybe try to eat other fish with less dioxin and mercury instead, that’s also good!
YG: About that – first of all congratulations on convincing the French government, it’s a great example – maybe the French politicians are a bit more forward-looking, but as a guy working in Brussels and listening to your definition of the exposome, I find it so complicated, and omnipresent. Really, it could be anything! Aren’t you afraid that the concept of the exposome could become the next buzzword, that it’ll become meaningless and be used by politicians here and there for any possible pseudo-scientific explanation of how the world works? Or even worse, that it gets diluted in the research priorities and nobody actually does true exposome research?
Did you know a ‘pie chart’ is called a ‘camembert’ in French? Might smell bad but it tastes very good! (from left to right – Vladimir S. Gordeev, Robert Barouki, Francesco Florindi, Dimitra Panteli)
RB: Things can always go wrong, there’s always this risk. And I agree that it’s much simpler to just say “let’s do the genome”. The hospital I work at is probably the strongest hospital in genetics, at least in France, so, although I had a bit of a challenge, I was able to bring to them things like metabolomics, and I hope this will help. But you’re right, things can go wrong, maybe [the exposome] is a little bit fuzzy. The challenge we have right now is to quickly provide some output. We don’t need to prove that we can do everything, we cannot say that we will model the human exposome in all conditions, it’s too far away. But we need to provide some initial outputs that are significant. For example, the interaction between nutrition and toxicants, like in the example I gave before, is the first thing that we could bring in, but there are others. For example, do you know that if you have a low socioeconomic status, you are more likely to have side-effects of air pollution? There can be many reasons for that: if you are in a better socioeconomic position, maybe you eat better or exercise. But it remains a fact that pollution is worse for the poorest. There are very significant political implications which you wouldn’t even imagine. For example, when the French government wanted to put taxes on diesel trucks, there was a revolution from the truck drivers. If you can convince them that they are the first victims of this type of exposure, you may have better luck with the evidence.
YG: Is there a flagship project that you can use as a beacon to the policy makers [beyond HEALS, HBM4EU, HELIX, Exposomics etc.]? And if not, who should be involved?
RB: Beyond the EU projects, there are many projects in the United States, but their philosophy is different. The most important one is called HERCULES, but it’s based purely on methods. They built a facility receives and analyzes different samples from epidemiological studies. They have this very practical approach. In Japan, they do mainly big cohort studies, rather than actual exposome work. I don’t know of any international project, like the Human Genome Project. I thought at one point that we should do the Human Exposome Project, but it’s so diverse, it’s really hard. Maybe one day, with the EU being the leader and involvement from the US, we will get there.
YG: Similar perhaps to the question before, having convinced the French government, what would be your wish list for policy-makers at the European level and how do you reach them to achieve it?
RB: My wish would be for more work to go on – and we have a responsibility to show some quick output, but we know it’s going to be a long-term work. So, my wish is that the support for this kind of research becomes sustainable. And I think it will be, I’m quite hopeful that it’s going to be sustained for a while. There must also be some coordination between projects, because the area is so complex. And if we can demonstrate that level of coordination to policy-makers, they will understand that they are supporting the scientists who are working together towards a single goal. That is, I think, very important, as well as to show that we are working on something that is going to be very important for health.
YG: Do you have a message for Young Gasteiners?
RB: You should open up to science, including hard science. There are many things there that can influence policy. You have to know that things are not always easy to demonstrate quite clearly, and very often you need to take decisions in the context of uncertainty. Get yourself involved in science a little bit, and see what’s going on – that could be very useful in policy. If you want one recommendation, that would be it!
This interview was written by the Young Gasteiners Francesco Florindi, Vladimir S. Gordeev and Dimitra Panteli