Interview with Professor Martine Vrijheid, an environmental epidemiologist and head of the ISGlobal Childhood and Environment Programme. Her research focuses on the impact of environmental exposures on child health and development. Professor Vrijheid coordinated the Horizon 2020 funded HELIX (Human Early Life Exposome) project, spearheading the push for a more holistic exposome-based approach to studying co-existing exposures and their joint effects on molecular responses and child health. She is continuing this research as leader of the new Horizon 2020 project ATHLETE (Advancing Tools for Human Early Life-course Exposome Research and Translation).
Why is it so important nowadays to put more effort into studying people’s environmental exposure?
Martine Vrijheid: We know that environmental factors and individual exposure to them can have a major impact on human health, in many cases even stronger than the genetic component.
We have noticed that there has been a lot of investment in research for the characterisation of the genome, but much less effort has been put into studying environmental risk factors in comparison, even if we know that we can act more on prevention. Therefore, we thought it was right to investigate these aspects further. What the research has done until now is study one type of exposure in relation to one specific health outcome. For example, there have been many studies on air pollution and heart disease. The exposome adopts a more holistic approach towards the environment, taking into account the multiple complex mixtures of environmental factors to which we are exposed in our daily lives. Tackling more than one environmental risk factor at a time is a fundamental shift when it comes to developing effective prevention strategies.
In your opinion, why is there more investment in genetic projects than in environmental risk exposure research?
Martine Vrijheid: Today, it is possible to sequence a person’s genome for a few hundred euros. This does not need to be repeated, as an individual’s genome remains unchanged for their entire lifespan.
The exposome is a different challenge. It changes every day and there are still many variables that we are unaware of, so we are unable to get a complete measurement. As part of a previous project, we measured hundreds of different environmental exposures in mothers and their children so we have a lot of information on that. Even now, we continue to monitor these exposures, carrying out data collection at precise points in time. Particularly important periods are the baby’s first thousand days (including the mother’s nine months of pregnancy) and adolescence.
How does the genome interact with environmental factors to impact on human health?
Martine Vrijheid: We don’t know so much, because these are difficult types of studies to do. We need extensive, far-reaching research, with lots of data on genetics and environmental exposure. The few valid examples in this area are found mainly in the field of oncology. For many diseases, however, these types of studies do not exist. Through the project, we want to give greater importance to environmental risk factors, which have been researched less than genetic ones.
Are paediatricians ideal figures for creating greater awareness of the importance of environmental exposure? What are the limits and opportunities in this context?
Martine Vrijheid: Paediatricians are aware of certain types of environmental risks, such as air quality. At the same time, there are areas where knowledge is scarce. There are hundreds of chemicals in the environment and we often know little about their possible effects on health. This obviously prevents an adequate level of risk awareness, not only among paediatricians but also among parents and doctors in general. It is therefore difficult to give sufficient recommendations about these potentially hazardous substances.
Endocrine disruptors, for example, are one group of chemicals whose effects on health are unknown or poorly understood. These chemicals are part of our everyday life because they are in cosmetics and plastics. We need to collect more data and then share it with regulators. Later, it will be necessary to engage not only paediatricians but also a large number of other figures to spread information at different levels of society.
In your opinion, what are the main barriers to this process?
Martine Vrijheid: What is missing, even in the regulatory phase, is a holistic approach. There is a tendency to regulate one chemical at a time, rather than a family of substances, even though they may have similar effects on health. This greatly slows down the legislative process and the establishment of appropriate policies. For every chemical we ban from the market, the production sector invents ten new ones.