2-methylbenzene-1,4-diyl bis{4-[3-(acryloyloxy)propoxy]benzoate}

Endpoint summary

Description of key information

Biodegradation

Key, CO₂-evolution test, OECD 301B, GLP: not ready biodegradable

Bioaccumulation

Key, Bioconcentration, Cyprinus carpio, 28 d, OECD 305, GLP: BCF = 31, not bioaccumulative

Additional information

Biodegradation

CO₂-evolution test, OECD 301B

The registered substance was tested for ready biodegradation in a CO₂-evolution test according to OECD Guideline 301B following GLP.

Purpose
The purpose of this assay was to provide information on the biodegradability of the test item in aqueous environment and thus serve as a rational basis for risk assessment for environmental fate in aqueous compartments.

Study Design
The test item was investigated for its ready biodegradability in a dioxide evolution test (former Sturm test) over a period of 28 days. The biodegradation was followed measuring the production of carbon dioxide (CO₂) which is a clear indication of biodegradation. The measured amount of carbon dioxide at the end of the test is compared with the calculated maximal theoretical production (ThCO2) and indicated as biodegradation degree in per cent. As the microorganisms oxidize only a part of the test substance and incorporate the rest into biomass, a degradation level >60 % is considered as sufficient biodegradation.

Result
Biodegradation
Under the test conditions the percentage biodegradation amounts to 3 % (mean value) after 28 days of incubation.
The test item can therefore be considered not to be readily biodegradable.

Biodegradation of Aniline
The reference item Aniline was sufficiently degraded to 95 % after 14 days and 96 % after 28 days of incubation thus confirming the suitability of the used activated sludge inoculum.

Biodegradation in the Toxicity Control
In the toxicity control containing both, the test item and the reference item Aniline, 42 % biodegradation was noted within 14 days and 49 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed to be not inhibitory on the activated sludge micro organisms.

Conclusion
The percentage biodegradation did not exceed 60 % within the 10-day window or after 28 days of incubation. The test item can therefore be considered not to be readily biodegradable.

Bioaccumulation

OECD 305

The study was conducted in compliance with GLP regulations and in accordance with the OECD Test Guideline No.305 "Bioconcentration : Flow-through Fish test” (before 2^ndOctober 2012).

10 fishes ofDanio rerio(Zebra fish) were used for acute toxicity test and 100 mg/L of Tween 80 was used as solubilising agent. LC50(96hr) was defined as >31 mg/L (limit test).

115 fishes (50 fishes for each test concentration, 15 fishes for control) ofCyprinus carpiowere used for the bioaccumulation test. Based on 96 hours LC 50 value the tests were performed in each 0.05 mg/L (1^stconcentration), 0.005mg/L (2^ndconcentration) of the test substance concentration and 0.15 mg/L (1^stconcentration) 0.015 mg/L (2^ndconcentration) of Tween 80 was used as solubiliging agent. Analysis of fish was done on 7^th, 14^th, 21^st, 26^thand 28^thdays after the start of exposure.

Result

Concentration test result

	Uptake period	7 day	14 day	21 day	26day	28 day
1^stconcentration	Test substance concentration in water (mg/L)	0.0457	0.0495	0.0520	0.0506	0.0476
	Concentration rate	8	9	8	20	6
		10	8	12	7	3
2^ndconcentration	Test substance concentration in water (mg/L)	0.00477	0.00502	0.00494	0.00494	0.00468
	Concentration rate	<11	<11	31	27	<12
		<11	25	<12	25	<12

Average recovery rate from water was determined as 94.5% (1^stconcentration) and 94.2% (2^ndconcentration) and average recovery rate from fish was determined as 86.2%.

Theoretical detection limit of BCF value was determined as≧1 (1^stconcentration) and≧12 (2^ndconcentration).

During 28 days exposure period BCF values showed less than 50fold through 28 days’ exposure period. Therefore 28 days after the start of exposure the concentration rate was regarded to reach steady state and the test was finished.

Bioconcentration factors (BCF) of the test substance in carp were 3 to 20 fold for the1^stconcentration and 25 to 31 fold for the 2^ndconcentration.