reaction mass of isomers of: C7-9-alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate

Endpoint summary

Additional information

Assessment of Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-,C7-9-branched alkyl esters (main constituent, parent):

Test organism	Test duration	Effect parameter	Effect value (mg/L)	Nominal/ measured	OECD guideline	Vehicle	Year of the study	Remarks
Brachydanio rerio	96h	LC50	>100	nominal	203	yes	1989	No effects in the range of solubility
Oncorhynchus mykiss	14d	NOEC	>=100	nominal	204	no	2000	No effects in the range of solubility
Brachydanio rerio	35d	NOEC	>=0.001	nominal	210	yes	2007	No effects in the range of solubility
Daphnia magna	48h	LC50	>100	nominal	202	no	2002	No effects in the range of solubility
Daphnia magna	21d	NOEC	1:3.2 dilution	loading rate 100mg/L	211	no	2000	Effects at the highest test concentration
Daphnia magna	21d	NOEC	>= 1mg/L	loading rate 1mg/L	211	no	2012	No effects in the range of solubility
Scenedesmus subspicatus	72h	LC50 NOEC	>3 >= 3	nominal	201	yes	1995	No effects in the range of solubility
Activated sludge	3h	EC50	> 100mg/L	nominal	209	no	1989

No toxic effects of Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-,C7-9-branched alkyl esters were observed in the range of solubility. The inhibition of the degradation activity of activated sludge is not anticipated when introduced in appropriate low concentrations. The substance is with high probability acutely and chronically not harmful to aquatic organisms.

Supporting assessment of major degradation product Metilox acid (CAS 20170-32-5)

Test organism	Test duration	Effect parameter	Effect value	Nominal/measured	OECD guideline	Vehicle	Year of the study	Remarks
Brachydanio rerio	96h	LC50	130 mg/L	nominal	203	yes	1989	A slight deposit was observed at conc. 180-320 mg/l (nominal) from the start of the test.
Daphnia magna	48h	LC50	> 121 mg/L	measured	202	no	2011
Pseudokirchnerella subcapitata	72h	ErC50 ErC10	>100mg/L 95mg/L	nominal	201	no	2009
Activated sludge	3h	EC50	> 100mg/L	nominal	209	no	1988

Acute toxicity test results are available for fish, Daphnia and algae. In an activated sludge respiration inhibition test, no adverse effects were observed. Slight toxic effects were observed in tests with fish and algae. However, these effects were caused by very high concentrations and are above the criteria for classification according to CLP.

Supporting assessment of the impurity Metilox (CAS 6386-38-5)

In a 96-h acute toxicity study to zebra-fish (Brachydanio rerio) under static conditions, the 96-h LC50 was 5.6 mg/L.  The LC0, based on mortality was 3.2 mg/L. 

In a 24-h acute toxicity to Daphnia magna under static conditions. The 24 -h EC50 was > 100 mg/L, the 24 -h EC0 based on immobilization was 5.8 mg/L.   

In a long-term toxicity to aquatic invertebrates test with Daphnia under semi-static conditions, the NOEC based on reproduction was 0.123 mg/L based on measured concentration and 0.16 mg/L based on nominal concentraions.

In a 72 h acute toxicity study to Scenedesmus subspicatus the NOEbC and EbC50 values based on cell number were 2.3 and 0.5 mg/L, respectively. 

In a 3 h acute toxicity study to sewage sludge microorganisms the IC50 value based on respiration rate was bigger than 100 mg/L after a 3 h contact time.

 

Supporting assessment of impurity 1 octanol (CAS 111 -87 -5)

Acute toxicity tests results are available for freshwater fish (Pimephales promelas), invertebrates (Daphnia magna) and algae (Pseudokirchnerella subcapitata). LC50 or EC50 values for the three organisms were 13.3, 20 and 14 mg/L respectively.

In waste-water treatment plant micro-organisms, octan-1-ol does not cause inhibition at the limit of water solubility. In view of the ready biodegradability, further information is not required in REACH.

A NOEC value of 1.0 mg/L (21 day reproduction) has been determined for the effects of octan-1-ol on reproduction and survival of the freshwater test organism Daphnia magna.

(ECHA disseminated data, August 04, 2015)