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Biodegradation in water

Estimation Programs Interface Suite was run to predict the biodegradation potential of the test compound   (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one (CAS no. 29461 -13 -0) in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one is expected to be not readily biodegradable.

Additional information

Biodegradation in water

Predicted data for the target compound (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one(CAS No. 29461-13-0) and various supporting weight of evidence studies for its structurally and functionally similar read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In a prediction done using the Estimation Programs Interface Suite was run to predict the biodegradation potential of the test compound   (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one (CAS no. 29461 -13 -0) in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical  (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one is expected to be not readily biodegradable.

 

In a supporting weight of evidence study from peer reviewed journal (2017), biodegradation experiment was conducted for evaluating the percentage biodegradability of test substance. The study was performed according to OECD Guideline 310 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test) under aerobic conditions. Initial test substance conc. used in the study was 20 mg/l, respectively. The percentage degradation of test substance was determined to be -2 and 5.1% by CO2 evolution parameter in 28 and 100 days, respectively. Thus, based on percentage degradation, test chemical is considered to be not readily biodegradable in nature.

 

For the test chemical, Persistence of the test chemical was determined in groundwater at Netherlands and Noordwijk, respectively (peer reviewed journal, 1981). The estimated half-life value of test chemical in groundwater at Netherlands and Noordwijk was determined to be 109.5 and 219 days, respectively. Thus, based on this, test substance is considered as persistent in water and can be evaluated to be not readily biodegradable in nature.

 

On the basis of above results for target chemical (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one (from modelling database, 2018), it can be concluded that the test substance (2α,4aα,8β)-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalen-8(5H)-one can be expected to be not readily biodegradable in nature.