'I look back on a wonderful career with impactful research'

Professor Hans Kromhout will retire on 5 December 2025. After an academic career of more than forty years, he will step down as Professor of Occupational Hygiene and Exposure Characterisation at the Faculty of Veterinary Medicine at Utrecht University (Institute for Risk Assessment Sciences). On 9 December 2025, he will deliver a farewell lecture entitled “From Lips to LEXCES: Occupational Hygiene and Epidemiology for Prevention and Compensation” in the auditorium of the Academy Building, together with Dick Heederik, who will also be retiring.

How do you look back on your professorship?

“Very positively. My chair was the very first professorship in Occupational Hygiene in the Netherlands. At Wageningen, I was also among the first group of students to specialise in this field, where research and prevention are so closely interconnected.”

Which research has had the greatest impact?

“That is a difficult question. I could look at citation counts, or choose based on societal impact. I’ll choose the latter. I must mention my collaboration with the Industrial Minerals Association Europe, which has lasted more than twenty years. Together with Remko Houba from the Netherlands Knowledge Centre for Occupational Health and Lung Diseases (NKAL), several PhD candidates, and local occupational hygiene specialists, we collected more than 50,000 personal dust measurements in 36 companies across 23 countries and 178 locations. We succeeded in reducing personal exposure to crystalline silica—a proven carcinogen—by a factor of three to four across an entire industry. We recently calculated that this has prevented 12% of silicosis cases and 20% of lung cancer cases. That is certainly something I am very proud of. I would love to see this remarkable project replicated, but unfortunately not all industries take their employees’ health equally seriously.”

Unfortunately not all industries take their employees’ health equally seriously

What are the biggest challenges for the future?

“There is no longer any academic programme in occupational hygiene in the Netherlands. For my successor, and for Dutch occupational hygiene in general, developing a (part-time) postgraduate programme will be essential—not only to maintain the field at its current level but also to expand and deepen it. This is especially important given the recent establishment of LEXCES, the national centre of expertise for substance-related occupational diseases. Research funding has also been made available for studies on the prevention and compensation of occupational diseases, which requires strong occupational hygiene involvement.”

“Another major challenge is engaging people who are truly exposed to occupational hazards in today’s society in occupational epidemiology research. Think of migrant workers, or of workers in India and China who produce our clothing, footwear, rubber tyres and steel. Or the men and women in Ethiopia who, for meagre wages and exposed to pesticides long banned in our own countries, grow cheap roses for Valentine’s Day. In current research, we often confine ourselves to concerned citizens living near flower fields and to white-collar workers. They are simply easier to reach and study. As a result, we risk losing sight of the people who are most at risk from work-related exposures.”

With the knowledge you have now, what would you have done differently?

“Nothing comes to mind. I look back on a wonderful career with impactful research in the Netherlands and far beyond. I am also very proud of my students and PhD candidates, who are highly successful both here and abroad. I would do it all again in a heartbeat.”

And what will you do now?

“I hope to spend more time cycling, alternating with my biggest hobby: draughts. I will also continue for the time being as editor-in-chief of the scientific journal Occupational and Environmental Medicine. And I still have several PhD candidates to guide to the finish line. I certainly won’t be bored.”