DL-thyroxin

Endpoint summary

Description of key information

According to a 48-hour Immobilisation Test (Limit Test) 48-hour static acute toxicity test with Daphnia magna the test item LEVOTHYROXINE ACID had no toxic effect on Daphnia at aquatic saturation (measured value: 0.32 mg/L; equivalent to 100 mg/L nominal concentration).

According to the 72-h algal growth inhibition test with Raphidocelis subcapitata, the obtained results showed that the test item LEVOTHYROXINE ACID had no toxic effect at aquatic saturation (measured value: 1.04 mg/L; equivalent to 100 mg/L nominal concentration). Accordingly, the 72-h EC50 value was determined to be > 1.04 mg/L (equivalent to > 100 mg/L nominal concentration). The 72-h NOEC was determined to be 1.04 mg/L (equivalent to 100 mg/L nominal concentration). All validity criteria were met.