(tetrapropenyl)succinic acid

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

According to the ECHA guidance on PBT/vPvB assessment (draft version 3.0, 2017) 2-(C12-rich-branched olefins from propene oligomerization)-1,4-butanedioic acid commonly known as (tetrapropenyl)succinic acid is regarded as being potentially persistent (P) or very persistent (vP) and bioaccumulative (B). However, there is not sufficient data to determine if the substance fulfils or not the toxicity (T) criteria.

Persistence Assessment

The OECD 301 F test conducted determined that the substance is not readily biodegradable. According to Table R.11 – 4 of the ECHA guidance on PBT/vPvB assessment (draft version 3.0, 2017), the substance can be therefore regarded as being potentially persistent (P) or very persistent (vP).

 

Bioaccumulation Assessment

Log Kow values were calculated for each of the constituents of the test substance (i.e.(tetrapropenyl)succinic acid). These values ranged from 3.2863 (for (E)-2-(nonenyl)butane-1,4-dioic acid) to 6.0859 (for (E)-2-(pentadecenyl)butane-1,4-dioic acid). Since all of the constituents are present in variable ranges in the test substance, the log Kow values were normalized to 100% based on the highest values of the percentages ranges for all constituents; the resulting weighted average log Kow is 4.76 (see table below).

Therefore, based on the log Kow of 4.76,(tetrapropenyl)succinic acid is potentially bioaccumulative (B) or very bioaccumulative (vB) as the log Kow is greater than the trigger value of 4.5 (ECHA guidance on PBT/vPvB assessment, draft version 3.0, 2017).

Constituent common name	Percentage range [%]	Log Kow	Maximum adjusted percentage [%]	Adjusted log Kow contribution
(tetrapropenyl)succinic acid	50-85	4.6861	53.46	2.51
(nonenyl)succinic acid	0-2	3.2863	1.26	0.04
(decenyl)succinic acid	3-7	3.7774	4.40	0.17
(undecenyl)succinic acid	10-25	4.2685	15.72	0.67
(tridecenyl)succinic acid	0-20	5.1772	12.58	0.65
(tetradecenyl)succinic acid	0-15	5.6683	9.43	0.53
(pentadecenyl)succinic acid	0-5	6.0859	3.14	0.19

 

Weighted average

4.76

 

No bioaccumulation experimental studies are known to have been undertaken. Therefore EPI Suite has been used to estimate the Bioconcentration Factor (BCF) based on theconstituents’ Log Kow values(which ranged from 3.2863 (for (E)-2 -(nonenyl)butane-1,4-dioic acid) to 6.0859 (for (E)-2-(pentadecenyl)butane-1,4-dioic acid).

BCF estimations were greatest using the Arnot-Gobas method (upper trophic) (compared to the regression based method). Therefore, based on the Arnot-Gobas (upper trophic) estimated BCFs (shown in the table below), it can be concluded that (tetrapropenyl)succinic acid meets the B criteria as the fish BCF is greater than 2000 for (tetradecenyl)succinic acid and (pentadecenyl)succinic acid.

Constituent common name	Log Kow	EPI-Suite calculated BCF [l/kgwwt]
(tetrapropenyl)succinic acid	4.6861	1154
(nonenyl)succinic acid	3.2863	153.7
(decenyl)succinic acid	3.7774	361.7
(undecenyl)succinic acid	4.2685	723.3
(tridecenyl)succinic acid	5.1772	1752
(tetradecenyl)succinic acid	5.6683	2364
(pentadecenyl)succinic acid	6.0859	2734

However maximum values calculated (which ranged from 153.7 to 2734 l/kg wet-wt) indicate that BCF of the any individual component of the substance would not meet the vB criterion (BCF =5000).

 

Toxicity Assessment

The substance does not demonstrate signs of short term aquatic toxicity in either the studies required as a part of the standard Annex VII and VIII information requirements or any other available information. There are no long term NOEC or EC10 values for marine or freshwater organisms less than 0.01 mg/L, and the substance does not meet the criteria for classification as carcinogenic, mutagenic or toxic for reproduction and there is no evidence of chronic toxicity meeting the criteria for classification in appropriate repeated exposure studies.

Comparison of the available data on the substance against the both the screening criteria and assessment criteria set out respectively in Sections 3.1.3 and 1.1.3 of Annex XIII to the REACH Regulation indicates that the existing data demonstrate a lack of applicable hazard classification and thus (tetrapropenyl) succinic acid does not meet the Toxicity (T) criterion.