Institute for Risk Assessment Sciences (IRAS)

Solutions to planetary environmental health challenges
Plastic bag floating in water

The impact of physical, biological and chemical factors in the environment on health is large. Nine million human deaths a year (16% of all deaths worldwide) are attributed to air, water, and soil pollution. These estimates are likely an underestimation of the real impact of the environment, as many of the emerging chemical and environmental concerns are not considered in these calculations. Even with this incomplete inventory, the economic costs of pollution are considerable, with healthcare and disability-related lost productivity estimated to amount to US $4.6 trillion per year, representing 6.2% of global economic output. Finding solutions for existing and emerging environmental challenges requires inter and transdisciplinary research.

Improving animal and human health

Our research programme is composed of experts in exposure science, toxicology, molecular biology, epidemiology, and veterinary and human medicine. Together we are generating critical insights in how the environment is affecting the health of humans and animals. We do so by combining observational studies on the relationship between exposure to biological, physical and chemical agents and health in the general environment, domestic and occupational settings with mechanistic insights obtained from experimental studies of availability, dose and mechanism of action of environmental contaminants in relation to their potential to induce adverse immune, neural and endocrine effects. The ultimate goal of the programme is to translate these insights into the development of effective prevention strategies to improve the health of animal and human populations.

Research themes

People in the city of Utrecht

Healthy Urban Living

How healthy is living in a large, densely populated city? The urban environment can influence public health in several ways, for instance through the accessibility of healthy transport and providing opportunities for physical activity. Read more

People cycling through rural landscape, between the cows.

Healthy Rural Living 

The rapid global transition towards increasingly intensive and high-input agriculture and livestock farming has led to deterioration of ecosystems. It has raised questions about potential impacts on human health. Read more



Antimicrobial resistance

Antimicrobial Resistance

Bacterial infections are a challenge to human and animal health, generally treated with antimicrobial therapies. However, the increase in antimicrobial resistance poses one of the major risks to health care worldwide. Read more

People walking on the street

Exposure Science & the Exposome

We know that most diseases result from a combination of genes and environment. Our genes alone do not determine our fate. For most diseases, environmental factors are more important. Exposome research is about discovering the non-genetic drivers of health and disease. Read more

Nightwork in hospital

Occupational Health

Working life exposures can lead to many diseases. Therefore, ensuring a safe and healthy work environment is important. In Utrecht, research is focused on environmental and occupational risk factors for chronic diseases, such as cancer. Read more


Toxicological mechanisms and effects

Utrecht University researchers investigate the cellular and molecular mechanisms of action of toxic substances (food-related products, health products, drugs and environmental contaminants) on the nervous system. Read more

Liver on achip

Alternative and in vitro models in toxicology

Utrecht University plays a leading role in the Netherlands concerning the use of alternatives to laboratory animals. They show that the transition to innovative and societally relevant science and policy is possible without animal testing. Read more

Child health

At Utrecht University we are working together with world-leading scientists in order to improve children's health. Children growing up today will eventually shape our world in the near future, so we are investing in the future. Read more

Longfoto van COVID-patiënt


Since March 2020 COVID-19 is among us and we have no choice but to deal with it. IRAS scientists incorporated the new challenges of the ongoing pandemic into their research. Read more