4-amino-m-cresol

Short-term toxicity to fish

Description of key information

In Fish Embryo Acute Toxicity test, the 96 hour LC50 of 4-Amino-m-cresol to Danio rerio (zebrafish) was 0.42 mg/L based on time-weighted mean measured concentration.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.42 mg/L

Additional information

The Fish Embryo Acute Toxicity test of 4-Amino-m-cresol to Danio rerio (zebrafish) was determined under semi-static conditions, for 96h, following the OECD guideline 236 and the GLP.

The dilution water used for conducting the tests was treated mains water that had been passed through activated carbon filters. The test vessels were 24-well polystyrene microtiter plates. A single plate was used for the control, each test concentration and the positive control. Twenty wells on each plate were filled with 2 mL of the appropriate control or test media. The remaining four wells in each plate were filled with treated mains water to act as internal controls.

The tested substance concentration was analysed by LC-MS/MS on new and old media. The nominal tested concentrations were 0 (control), 0.19, 0.41, 0.91, 2, 7.5 and 10 mg/L. The tested concentrations decrease quickly before the media renewal. Analysis of the tested solutions at 0 and 48 hours (new media) showed measured concentrations to range from 68% to 117% of nominal. Analysis of the tested solutions at 24 and 72 hours (old media) showed measured concentrations to range from 2% to 66% of nominal. The concentrations were expressed as time-weighted mean measured concentrations : 0.12;  0.23;  0.39;  0.71;  1.1 and 2.5 mg/L and this range of concentrations induces 75%, 95%, 50%; 0%, 0%, 0% of eggs survival respectively, and 90% in the control. The mortality is based on the observation of at least one of the following criteria : coagulation of the egg, absence of somite formation, non-detachment of the tail and lack of heart beat.

The 96 hour LC50 of 4-Amino-m-cresol to Danio rerio (zebrafish) was 0.42 mg/L based on time-weighted mean measured concentration..

All the validity criteria were fulfilled except the temperature which was not maintained at 26 ± 1°C during the test . However this deviation was considered as not having any impact on the results since the control embryo overall survival and hatching met the validity criteria.