ISGlobal Researchers Travel to the Smallest Capital in the World: a Story About Mercury

The 6th prenatal programming toxicology conference PPTOX VI, an event gathering toxicologists, public health doctors and environmental scientists, took place in May 27-30 2018 in Torshavn in the Faroe Islands. This singular place, located in the North Atlantic between Shetland Islands and Iceland, was in fact perfectly suited for hosting such event.

The Faroe Islands were home to the first longitudinal study demonstrating the detrimental effect of mercury and organochlorine exposure during pregnancy (...) in children

The Faroe Islands were home to the first longitudinal study demonstrating the detrimental effect of mercury and organochlorine exposure during pregnancy on the nervous and immune system in children. The Faroes are a self-governing nation of 50,000 inhabitants, under the external sovereignty of the Kingdom of Denmark. Surprisingly, they hold the oldest parliament in the world, which can be traced back to the Viking era, more than one thousand years ago. Despite its small population, it holds a strong cultural identity, with an emphasis on tradition and the arts, an independent language and flag, and is widely known as an ideal epidemiological setting.

Within this population, different waves of birth cohorts have recruited approximately 2,300 Faroese children since 1985. The initial work focused on the effects of mercury in the diet of the Faroese and expanded to include polychlorinated biphenyls (PCBs) and perfluorinated alkylated substances (PFAS). In this North Atlantic fishing community, they have identified alarming high levels of mercury, organochlorines and perfluorinated compounds ingested through the consumption of seabirds and whale meat—a practice that is both culturally and economically important.

They have identified alarming high levels of mercury, organochlorines and perfluorinated compounds ingested through the consumption of seabirds and whale meat

After the results of the Faroe islands birth cohort study came out, the population was warned of the potential side effects of consuming pilot whale products, in particular for children, pregnant women and even mothers-to-be. It took perseverance and cultural tact to sensitize the population to these issues.

Due to the island’s inhospitable weather for growing crops, the Faroese main source of food has been fish and lamb, with pilot whale being a prized catch due to its high nutritional value. As late as in the 1970s, school doctors even recommended parents to make sure that children have blubber (whale fat) for breakfast. Nowadays, the younger Faroese are aware of the danger and have drastically reduced their consumption, in particular thanks to communication efforts by the local public health authorities and international support.

Nowadays, the younger Faroese are aware of the danger and have drastically reduced their consumption, in particular thanks to communication efforts

At the congress, ISGlobal researchers Maribel Casas, Charline Warembourg, Jordi Sunyer, Parisa Montazeri and myself presented results about environmental threats in children from Spain and the rest of Europe. Fish consumption, and subsequently mercury exposure, is particularly high in the Spanish INMA - Environment and Childhood Project, a birth cohort led by ISGlobal. Mean levels of 8.8 µg/L of total mercury were found in cord blood of Spanish newborns – lower than the 22.9 µg/L found in the first Faroe Cohort (1986-1987) but higher than the more recent Cohort (4.59 µg/L) found in 2007–2009, also in cord blood.

In the HELIX study, where we analysed omics signatures in children’s urine and blood, we found that perfluorinated compounds, arsenic and mercury were most strongly associated with the metabolic footprint of children, in particular with polyunsaturated fatty acids (PUFA). Other presentations at the conference provided further insights into mercury metabolism through the gut microbiota and revealed variable individual capacity to eliminate such toxicants.

The Faroe island birth cohorts gave us a lesson on the role of public health in science

Overall, the Faroe island birth cohorts gave us a lesson on the role of public health. We can monitor contaminant levels among vulnerable populations, in this case children, and study health consequences of these compounds, but this research has a context. In the case of the Faroese population, fish eating is an important part of their culture- it has been their only source of food for centuries and their main economic activity (20% of their GDP).  They have to a certain extent respected their natural environment and tradition by holding on to it. The local health policies therefore focused on targeting the most vulnerable population to reduce the health burden related to whale contamination. The award-winning documentary “Islands and whales” (2016) captured in a sensitive, profoundly moving way this difficult choice the Faroe Islanders must make between health and tradition.

There are many controversial issues related to fish consumption

There are many controversial issues related to fish consumption: first, at a public health level regarding the trade-off between nutrient intake and toxic exposure; second, from the marine conservation and food security perspectives, due to overfishing and plummeting marine biodiversity.

A global eco-system approach should be used to advice the population on what to eat -and in general on their lifestyle in general-, depending on where they live and theiry cultural background.

Environmental health research is global in its essence, including human (all) health, one health and planetary health. In the case of the Faroe, the carbon footprint and high price of imported food may need to be taken into account when elaborating health policies. It is ironic that this remote archipelago, which is not responsible for any significant mercury pollution, must now give up a traditional food source, which had provided energy and essential nutrients to the population for many centuries, and probably replaced it nowadays by processed food.