Reaction products of furan-2,5-dione and octadec-1-ene

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

The substance was shown to be readily biodegradable in a ready biodegradability closed bottle test conducted on an analogue substance through read-across: 60% degradation was observed in 28 days, although the 10-day window was not achieved. The substance has also been shown to hydrolyse rapidly in the presence of water. Therefore, the substance is determined to be “not persistent" (“not P”) and “not very persistent" (“not vP”) based on screening criteria.

Screening-level data indicate that the substance may be considered to be "potentially bioaccumulative" (“potentially B”) and "potentially very bioaccumulative" (“potentially vB”). The octanol-water partition coefficient was predicted by QSAR as log K_ow= 9.36, which is above the screening criterion of log K_ow ≤ 4.5, below which a substance may be considered to be both “not B” and “not very B”.  However, there is evidence that indicates that the substance may not be bioaccumulative. The substance has been shown to rapidly hydrolyse to octadecenyl succinic acid in the presence of water; the bioconcentration factor predicted by QSAR for this hydrolysis product is 56.23, which is not indicative of the potential for bioaccumulation. The substance was shown to be readily biodegradable in a ready biodegradability closed bottle test: 60% degradation was observed in 28 days, although the 10-day window was not achieved; substances that degrade rapidly in the environment “are likely to be rapidly metabolised in organisms” in accordance with ECHA guidance (ECHA, Guidance on information requirements and chemical safety assessment, Chapter R.7C, Endpoint-specific guidance, Section R.7.10.3.4, p. 26, November 2012).  However, aquatic bioaccumulation testing was not conducted on the substance, and therefore the bioaccumulative properties of the substance cannot be definitively determined. Therefore, no conclusion can be reached based on available information; the substance is considered to be “potentially B” and “potentially vB”. 

The evaluation of short-term aquatic toxicity tests conducted on an analogue substance through read-across indicate that fish may be the most sensitive trophic level; the 96-h NOEC and the 96-h EC₅₀ value reported from the acute fish toxicity test on Leuciscus idus were 10 mg/L and > 10 mg/L, respectively; the 48-h EL₅₀ in Daphnia magna was 36.3 mg/L and the 72-h E_rL₅₀ in Desmodesmus subspicatus was 85.1 mg/L. These results provide a screening-level determination that the substance is “presumably not toxic” (“presumably not T”) with respect to aquatic organisms. The substance does not exhibit the properties of a carcinogenic, mutagenic or reproductive toxicant [CMR], nor does the substance exhibit specific target organ toxicity in a repeated-dose study [STOT-RE]). These results provide a definitive determination that the substance is "not toxic" (“not T”) with respect to mammalian endpoints. 

Screening criteria indicate that the substance is “not P”, “not vP”, and “presumably not T” with respect to aquatic toxicity; the substance has been definitively shown to be “not T” with respect to mammalian toxicity. Although a definitive determination cannot be made with respect to the bioaccumulation endpoint, the screening criterion indicates that the substance may be considered to be “potentially B” and “potentially vB”, in the absence of definitive data.  It is not necessary to have definitive criteria for all five endpoints to make the determinations as to whether the substance is “not PBT” and “not vPvB”. The determination only requires that “each of the three properties persistency, bioaccumulation and toxicity need to be considered in conjunction” (Chapter R.11, “PBT Assessment”, Guidance on information requirements and chemical safety assessment, ECHA, November 2012, Section R.11.1.2.2, p. 15). 

In summary, based on data available to date, the substance is “not PBT” (not P, potentially B, and not T), and is “not vPvB” (not vP, potentially vB).