Publication Abstract

The Light/Dark Transition Test (LDTT) is a widely used assay for assessing the effect of chemicals in zebrafish embryos. However, the lack of standardization in LDTT protocols is making the comparison of results across studies and laboratories difficult, limiting its application in chemical hazard and risk assessment. To address this issue, researchers from 15 different research entities collaborated to develop a standardized LDTT protocol. The present framework is expected to provide a reliable data foundation for performing the LDTT test with zebrafish embryos and advancing our understanding of chemical hazard and risk assessment. The protocol was applied in a small case study involving 7 international institutions, which demonstrated consistency, reproducibility, and reliability of the LDTT framework across different laboratories. The results showed that the behavioral profiles of negative controls in zebrafish embryos were highly similar among different labs, confirming the reliability and robustness of the LDTT when performed with the described protocol. Further development of the protocol will lead to improved reproducibility and comparability of LDTT results, facilitating data sharing and collaboration among institutions and regulatory bodies. Finally, this study might contribute to future development for more effective and standardized protocols for assessing neurotoxicity in zebrafish embryos and may lead to recommendations for integrating standardized LDTT protocols into regulatory frameworks.

Riccardo Massei, Richard Ottermanns, Katja Schröder, Inês Domingues, Marta S. Monteiro, Maria D. Pavlaki, Holly J. Puglis, Jason T. Magnuson, Beatriz Molina Martinez, Arantza Muriana, Oihane Jaka, Sarah Johann, Edwin P. Zwart, Ellen V.S. Hessel, Pernille Ambus Kjær, Henrik Holbech, Marion Sebire*, Luigi Margiotta-Casaluci, Lisa Bauer, Thomas Braunbeck, Dries Knapen, Lucia Vergauwen, Kato Huyghe, Abigail N. Henke, Ba Reum Kwon, Bryan W. Brooks, Lisa Truong, Robyn Tanguay, Colette vom Berg, Maria Christou