Dr. Chiel Jonker

Biography

Chiel Jonker is a senior researcher consultant in the Toxicology division at the Institute for Risk Assessment Sciences (IRAS) at Utrecht University. His work primarily focuses on the exposure assessment of chemicals in the environment and laboratory settings, employing both in vivo and in vitro (bio)assays. As a trained environmental chemist and ecotoxicologist, Chiel's environmental research consultancy activities aim to identify sources of toxic chemicals and gain a better understanding of the risks associated with the environmental distribution of these chemicals. He is particularly driven by processes such as sorption and bioaccumulation. Currently, his research is directed towards per- and polyfluoroalkyl substances (PFAS), which are chemicals that persist in the environment and can lead to significant human exposure. Chiel has extensive experience with hydrophobic chemicals including oils, polycyclic aromatic hydrocarbons, and pesticides such as DDT, and he has developed specific exposure quantification techniques like passive sampling methods. He strives to improve the performance and resulting data quality of in vivo and in vitro assessments through better dosing and exposure quantification, alongside meticulous data interpretation. His scientific motive revolves around the development and enhancement of experimental methods, with a particular focus on the experimental quality of difficult-to-test chemicals and the necessity of high-quality chemical analyses using techniques such as GC-MS and LC-MS.

Research Interests