Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

For 1,3 -Bis (4 -hydroxy benzoyl) benzene short-term toxicity tests are available in green algae and aquatic invertebrates, including a respiration test with activated sludge. In addition, a reproduction test with daphnia and an early life stage toxicity test in fish test were conducted as part of a PMN in the US. Due to the low solubility of the test item, procedures were based on the test methods described in the OECD series on testing and assessment number 23, 2000.

Short-term toxicity data

- The acute toxicity of 1,3-Bis (4-hydroxy benzoyl) benzene was investigated in a GLP compliant study according to OECD 202. No immobility was observed at any of the concentrations of 1,3-Bis (4-hydroxy benzoyl) benzene tested. The EC50 for immobilization (48h-EC50) for Daphnia magna was > 0.33 mg/L, measured concentration being considered to be the maximum soluble concentration of the test item in test medium at a loading rate of 100 mg/L. 

- A GLP compliant guideline study is available for the toxicity in algae (Raphidocelis subcapitata). Under the conditions of the study, no inhibition of growth rate or inhibition of yield was recorded at any of the concentrations of tested. The EC50 for both growth rate and yield inhibition (72h-ErC50and 72h-ErC50, respectively) was > 0.28 mg/L i.e.TWA concentration being considered to be the maximum soluble concentration of the test item in test medium at a loading rate of 100 mg/L. The 72h-NOEC for both growth rate and yield inhibition was ≥ 0.28 mg/L.

- The effect of the test item on the respiration of activated sewage sludge was assessed in a valid GLP study performed according to OECD TG 209. The test item was not toxic to waste water bacteria (activated sludge) at a concentration of 1000 mg/L (NOEC). The EC50 was above 1000 mg/L.

Long-term toxicity data

Reliable studies on chronic toxicity of 1,3-Bis (4-hydroxy benzoyl) benzene to the aquatic environment are available for three trophic levels: algae, invertebrates and fish:

- In the study of growth inhibition of the algae species Raphidocelis subcapitata performed by Charles River (2018), no inhibition of growth rate or inhibition of yield was recorded at any of the concentrations of tested. The 72h-NOEC for both growth rate and yield inhibition was ≥ 0.28 mg/L.

- A GLP-compliant guideline study is available for the long-term toxicity in aquatic invertebrates (D. magna). Under the conditions of this study 1,3-Bis (4-hydroxy benzoyl) benzene did not affect reproduction, parental mortality and growth of Daphnia magna at the maximum solubility in test medium, i.e. at 0.16 mg/L, after 21 days of exposure (NOEC).

- A chronic fish study according to OECD 210 was performed with fathead minnow (Pimephales promelas) under flow-through conditions. Under the conditions of the study 1,3-Bis (4-hydroxy benzoyl) benzene did not affect the hatching success, post-hatch survival or growth of the larvae at concentrations up to and including 0.10 mg/L (NOEC). Hence the LOEC was >0.10 mg/L.

Additional information