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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Biodegradation in water:

The test chemical piperazine 2-hydroxypropane-1,2,3-tricarboxylate (3:2) (salt) was estimated to be not readily biodegradable in water, by QSAR toolbox.

Additional information

Biodegradation in water:

Predicted data for the test compoundPiperazine citrate(CAS No. 144-29-6)and the study for its read across substance were reviewed for the biodegradation end point and is presented below as weight of evidence approach:

In key study, Biodegradability of 2-hydroxypropane-1,2,3-tricarboxylate (3:2) (salt) (CAS no. 144 -29 -6) is predicted using OECD QSAR toolbox version 3.3 (2018) with log Kow as the primary descriptor. Test substance is estimated to undergo 79.422% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 2-hydroxypropane-1,2,3-tricarboxylate (3:2) (salt) was estimated to be not readily biodegradable in water.

Supporting above prediction, Estimation Programs Interface Suite (EPI suite, 2016) was run to predict the biodegradation potential of the test compound Piperazine citrate (CAS no. 144 -29 -6) 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 Piperazine citrate is expected to be readily biodegradable.

Further, Biodegradation study was conducted according to OECD TG 301 C guideline for evaluating the percentage biodegradability of read across substance Piperazine (Kondo, M. et. al; 1988). Initial test substance conc. used in the study was 20 mg/l. Namely, a water, acetone or DMSO solution (0.1 ml) of the test chemicals was added to a mixture of river/sea water (4.9 ml) from an unpolluted area and an autoclaved solution (5.0ml) of 0.2% peptone in a sterile test tube with a tight plug. After sealed with film and fixed at an angle of 30°in a dark box, the test tubes were incubated at 30°C and shaked at 120rpm. Inoculum used for the study was mixed culture obtained from different sources (Sea water from Tama river and River water from Enoshima Beach). The percentage degradation of test substance was found to be 20% and 77% in 3 days, respectively. Thus, the substance Piperazine was determined to be readily biodegradable in nature.


On the basis of above results for target as well as read across substance and by applying weight of evidence approach, it can be concluded that the test substancePiperazine citratecan be expected to be readily biodegradable in nature.