Toxicokinetic/Toxicodynamic models and their role in PollinERA

Toxicokinetic and toxicodynamic (TKTD) models describe what happens inside a living organism following exposure to a chemical. They help explain how a substance enters and accumulates in the body (toxicokinetics), how it causes damage (toxicodynamics), and how these effects influence the organism's survival and other biological functions.

TKTD models are important tools in environmental risk assessment, as they help scientists understand and predict the effects of chemical exposure over time. By linking exposure to biological responses, they can provide insights into how organisms are affected by different exposure levels and durations, supporting more realistic predictions of the potential impacts of pesticides.

However, most existing TKTD models have been developed for aquatic organisms, which are typically exposed to chemicals through a single main route: the surrounding water. For terrestrial organisms, including pollinators, exposure is more complex. Bees, butterflies, moths and hoverflies can encounter pesticides through different pathways, such as contaminated food, contact with treated plants or other environmental sources. These multiple exposure routes make it more challenging to understand how chemicals enter their bodies and how exposure translates into biological effects.

One of the ways the PollinERA project aims to advance pesticide risk assessment is by improving TKTD models to better reflect the specific characteristics of terrestrial pollinators. We are working on developing robust, generalised TKTD models that can account for different exposure pathways and help predict the effects of pesticides across different pollinator groups. By taking these models a step further, PollinERA aims to improve our ability to understand and predict pesticide impacts not only on individual organisms but also at the population level.

Interested in learning more? Watch the video below, where PollinERA partners Andreas Focks and Florian Schunck from Osnabrück University introduce TKTD models and explain why they need to be further developed for terrestrial organisms.