Dibenzo[b,f]cyclohepten-1-one

Endpoint summary

Description of key information

Short-term toxicity to fish

For chemical 1H-dibenzo[a,d][7]annulen-1-one (Cas no. 2222-33-5), based on effect on mortality of the fish, the 96 hr LC50 value was determined to be >2.5 mg/l.

Short term toxicity to aquatic invertebrates

The short term toxicity to aquatic invertebrates test was performed according to the OECD Guideline 202. The test was performed on Daphnia magna for 48 hrs using 5H-dibenzo[b,f]cyclohepten-1-one at 1.9 mg/l concentration. After experiment it was determined that the EC50 value of 5H-dibenzo[b,f]cyclohepten-1-one (2222-33-5) in Daphnia magna was 1.9 mg/l based on immobilisation effect. On the basis of CLP regulation 5H-dibenzo[b,f]cyclohepten-1-one (2222-33-5) was considered likely to be toxic to aquatic invertebrates and can be classified in aquatic chronic 2 category based on CLP regulation.

Toxicity to aquatic algae and cyanobacteria

Short term toxicity to green algae study was carried out for 72 hrs (J-CHECK, 2016). The study was performed according to OECD Guideline 201 (Alga, Growth Inhibition Test). The study was based on the effects of the test compound 1H-dibenzo[a,d][7]annulen-1-one on green algae in a static fresh water system. Based on effect on growth rate of the test organism green algae, the 72 hr EC50 and NOEC value was determined to be 0.14 and 0.011 mg/l, respectively and on the basis of AUG, the 72 hr EC50 and NOEC value was determined to be 0.09 and 0.022 mg/l, respectively. Thus, based on the EC50 value, it can be concluded that the substance 1H-dibenzo[a,d][7]annulen-1-one can be considered as toxic to aquatic organisms and thus can be classified as aquatic acute category 1 as per the CLP classification criteria.

Additional information

Short-term toxicity to fish

Short term toxicity to fish study was carried out for 96 hrs. The study was performed according to OECD Guideline 203 (Fish, Acute Toxicity Test). The study was based on the effects of the test compound 1H-dibenzo[a,d][7]annulen-1-one on fish in fresh water system. Based on effect on mortality of the test organism fish, the 96 hr LC50 value was determined to be >2.5 mg/l. Thus, based on the LC50 value, it can be concluded that the substance 1H-dibenzo[a,d][7]annulen-1-one can be considered as toxic to fish and thus can be classified as aquatic acute category 2 as per the CLP classification criteria.

Short term toxicity to aquatic invertebrates

The study of 5H-dibenzo[b,f]cyclohepten-1-one to aquatic invertebrate was performed which was summaries with one experimental study and prediction of the chemical as follows:

Short term toxicity to aquatic invertebrates was studied for 5H-dibenzo[b,f]cyclohepten-1-one by J-check (Results of Eco-toxicity tests of chemicals conducted by Ministry of the Environment in Japan,2000).The test was performed in Daphnia magna according to the OECD Guideline 202. The time period for treatment was 48 hrs. After the experiment, the EC 50 value for Daphnia magna by 5H-dibenzo[b,f]cyclohepten-1-one was determined to be 1.9 mg/l.

In prediction done by SSS (2017) using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptorand considering the five closest read across substances, the short term toxicity on aquatic invertebrates was predicted for5H-dibenzo[a,d]cyclohepten-5-one (CAS no 2222-33-5).From prediction the EC50 value was estimated to be 132.63mg/L on the basis of intoxication for Daphnia magna for 48 hrs duration.

Thus based on QSARprediction,5H-dibenzo[b,f]cyclohepten-1-one was considered to be non hazardous to aquatic invertebrates but as the experimental study from J-check concluded that 5H-dibenzo[b,f]cyclohepten-1-one was likely to be toxic to aquatic invertebrate. Hence, based on the EC 50 value which is 1.9 mg/l, 5H-dibenzo[b,f]cyclohepten-1-one was classified in aquatic chronic 3 according to the CLP regulations.

Toxicity to aquatic algae and cyanobacteria

1 experimental key studyfor the target chemical1H-dibenzo[a,d][7]annulen-1-one (CAS no. 2222-33-5) which are supported further by total 2 studies (from authoritative database) for its closest structurally similar read across substance with logKow as the primary descriptor were reviewed for the toxicity to aquatic algae and cyanobacteria end point which are summarized as below:

 

In a key study fromauthoritative database(J-CHECK, 2016) for target chemical1H-dibenzo[a,d][7]annulen-1-one (CAS no. 2222-33-5), short term toxicity to green algae study was carried out for 72 hrs. The study was performed according to OECD Guideline 201 (Alga, Growth Inhibition Test). The study was based on the effects of the test compound 1H-dibenzo[a,d][7]annulen-1-one on green algae in a static fresh water system. Based on effect on growth rate of the test organism green algae, the 72 hr EC50 and NOEC value was determined to be 0.14 and 0.011 mg/l, respectively and on the basis of AUG, the 72 hr EC50 and NOEC value was determined to be 0.09 and 0.022 mg/l, respectively.

 

In a supporting data for read across compound Anthraquinone (CAS no. 84 -65 -1) fromauthoritative database(J-CHECK, 2016), short term toxicity to green algae study was carried out for 72 hrs. The study was based on the effects of the read across compound Anthraquinone on green algae in a static fresh water system. Based on effect on growth rate of the test organism green algae, the 72 hr EC50 and NOEC value was determined to be > 0.035 and 0.035 mg/l, respectively and on the basis of areas under the growth curves, the 72 hr EC50 and NOEC value was determined to be > 0.4 mg/l, respectively.

 

Additional supporting study for toxicity to aquatic algae and cyanobacteria for read across chemicalAnthraquinone (CAS no. 84 -65 -1)was carried out for 90 mins (ECOTOX database, 2016). The study was based on the effects of the read across compound Anthraquinone on green algae in a static fresh water system. Based on effect on physiology of the test organism algae, the EC50 value was determined to be 0.684 mg/l, respectively. 

 

Based on the overall reported results for target chemical 1H-dibenzo[a,d][7]annulen-1-one (from authoritative database J-CHECK, 2016) and for its read across substance (from J-CHECK and ECOTOX authoritative database), it can be concluded that the test substance 1H-dibenzo[a,d][7]annulen-1-one can be considered as toxic to aquatic organisms and thus can be classified as aquatic acute category 1 as per the CLP classification criteria.