Abstract
Background
The Fish Embryo Acute Toxicity (FET) test with the zebrafish (Danio rerio) embryo, the OECD test guideline (TG) 236, has been designed as an alternative for acute fish toxicity testing such as the OECD Acute Fish Toxicity Test (TG 203). To provide equivalent sensitivity to the acute fish test, the original FET test was designed to use only four morphological core endpoints: coagulation of the embryo, lack of somite formation, lack of heart beat, and non-detachment of the tail. These endpoints were selected due to (1) their association with mortality, directly or indirectly, (2) improve the practicality for screening by well-trained technical staff, and (3) the endpoints being relatively simple morphological alterations.
Results
With the growing need to understand the developmental toxicity of compounds found in the environment, the FET protocol has repeatedly been extended to a multitude of additional morphological endpoints that also allow the monitoring of teratogenicity. As the extensive use of the FET test has generated a multitude of observations in the scientific literature, a harmonisation of the terminology used for the description of the morphological effects seen after chemical exposure has become necessary.
Conclusion
For this end, the present communication provides an overview of both common and selected more specific morphological effects seen in zebrafish embryos after exposure to a wide variety of chemical substances together with suggestions for a harmonised nomenclature.
The Fish Embryo Acute Toxicity (FET) test with the zebrafish (Danio rerio) embryo, the OECD test guideline (TG) 236, has been designed as an alternative for acute fish toxicity testing such as the OECD Acute Fish Toxicity Test (TG 203). To provide equivalent sensitivity to the acute fish test, the original FET test was designed to use only four morphological core endpoints: coagulation of the embryo, lack of somite formation, lack of heart beat, and non-detachment of the tail. These endpoints were selected due to (1) their association with mortality, directly or indirectly, (2) improve the practicality for screening by well-trained technical staff, and (3) the endpoints being relatively simple morphological alterations.
Results
With the growing need to understand the developmental toxicity of compounds found in the environment, the FET protocol has repeatedly been extended to a multitude of additional morphological endpoints that also allow the monitoring of teratogenicity. As the extensive use of the FET test has generated a multitude of observations in the scientific literature, a harmonisation of the terminology used for the description of the morphological effects seen after chemical exposure has become necessary.
Conclusion
For this end, the present communication provides an overview of both common and selected more specific morphological effects seen in zebrafish embryos after exposure to a wide variety of chemical substances together with suggestions for a harmonised nomenclature.
| Original language | English |
|---|---|
| Article number | 122 |
| Number of pages | 18 |
| Journal | Environmental Sciences Europe |
| Volume | 32 |
| DOIs | |
| Publication status | Published - 29 Sept 2020 |
Bibliographical note
FundingOpen Access funding enabled and organized by Projekt DEAL. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under Grand agreement No 681102.
Data Availability Statement
Supplementary information accompanies this paper at https://doi. org/10.1186/s12302-020-00398-3.Keywords
- Zebrafish, OECD TG 236
- Embryo toxicity
- FET test
- Teratogenicity
- Spinal defects
- Lordosis
- Kyphosis
- Scoliosis
- Craniofacial deformation
- Yolk malabsorption