ZeTox – Toxicology Services


icon-early-life-stage-toxicity Early-life Stage Toxicity

Long-term effects require repeated exposures and can take months or years to appear. It is the so-called "chronic toxicity". Cancer, genetic alterations, allergic reactions, hormonal alteration, and toxicity of the central nervous system are some examples. These effects can be predicted from studies performed with zebrafish larvae at early life stages.

This assay is addressed to determine the lethal and sub-lethal effects of chemicals on the early life stages of the fish tested.

Early-life Stage Toxicity

An alternative method for high throughput chronic toxicity assessment in vivo.


Valuable information for the estimation of the chronic lethal and sub-lethal effects of a substance in only 30 days.

Applicable to a wide range of compounds regardless of mode of action, volatility, solubility and hydrophobicity.

Simultaneous assessment of general malformations and abnormal behaviours.

Method description

Incubation of embryos with 5 different logarithmic concentrations of the molecule of interest spaced by a constant factor 3 from 0 to 30 days post fertilization (dpf). Assay performed according to the OECD guideline 210.

Figure 1. Representation of the zebrafish larvae incubation with the compound of interest for 30 days.


Determination of the following parameters at days 10, 20, and 30:

  • Stage of embryonic development
  • Hatching
  • Survival
  • General morphological abnormalities
  • Abnormal behavior
  • Weight
  • Length

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  1. OECD. 2013. Test No. 210: Fish, Early-life Stage Toxicity Test.