Alkenes, C13-14, hydroformylation products, low boiling

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Overall conclusion: Based on the assessment described in the subsections below the submission substance is not considered as PBT / vPvB.

Rationale: Alchisor TAL 145 can be characterised according to three constituents: Hydrocarbons C11-C14 aliphatics, n-alkanes, isoalkanes, cyclics, aromatics (2-25%), dodecan-1-ol and tetradecan-1-ol. As defined in the ‘Read-Across Justification Document’ in section 13 of the IUCLID file, data provided for these constituents when considered together is representative of Alchisor TAL 145 and suitable for assessment purposes. Alchisor TAL 145 constituents do fulfil the screening criteria for toxicity, but not for persistence or bioaccumulation. The overall conclusion is that constituents of Alchisor TAL 145, and therefore, Alchisor TAL 145, do not meet the PBT or vPvB criteria. No further testing is required.

Persistence assessment

Results of the ready biodegradability tests with Alchisor TAL 145 constituents (namely C9-C14 aliphatics (2-25% aromatics), tetradecan-1-ol and dodecan-1-ol) demonstrate that they are readily degraded under aerobic conditions in fresh waters (Werner 1993 & ExxonMobil Biomedical Sciences, Inc. 1995). In accordance with the protective approach defined in the ‘Read-Across Justification’ document, the most sensitive study result from all the constituents can be applied to the full Alchisor TAL 145 biodegradation in water endpoint. Alchisor TAL 145 can be regarded as readily biodegradable. Consequently in line with the detailed guidance Alchisor TAL 145 does not fulfil the criteria for Persistence (P).

Bioaccumulation Assessment

According to Annex XIII of Regulation (EC) No 1907/2006 and to the Guidance on information requirements and chemical safety assessment Chapter R.11 (PBT Assessment, ECHA (2008)), a substance does not fulfil the criteria “bioaccumulative (B)” or “very bioaccumulative (vB)” if the bioconcentration factor (BCF) is below 2000 or 5000 respectively or if the log Kow is below 4.5.

The log Kow for Alchisor TAL 145 is greater than 4.5 (Log Kow 7.7 @ 25°C). There are no bioaccumulation studies studies for Alchisor TAL 145. However, the constituents (namely C9-C14 aliphatics (2-25% aromatics), dodecan-1-ol and tetradecan-1-ol) cannot be regarded as bioaccumulative in aquatic, sediment or terrestrial organisms, as described below. The data requirement for bioaccumulation studies is waived because studies are either unsuitable, as for C9-C14 aliphatics (2-25% aromatics), or technically unfeasible, as for dodecan-1-ol and tetradecan-1-ol and no reliable measured bioconcentration information is available for these constituents of Alchisor TAL 145.

In the case of C9-C14 aliphatics (2-25% aromatics) the substance is a UVCB hydrocarbon and bioaccumulation testing is not appropriate for this complex substance, however, BCF’s were calculated for representative hydrocarbon structures using the BCFWIN v2.16 model within EPISuite 3.12 or EUSES and incorporated into the PETRORISK model. The PETRORISK model predictions for hydrocarbons ranged from 45.5 to 21,710, although supporting information reported in CONCAWE’s approach (Lampi et al., 2010) provides evidence of over-estimation when BCF’s are predicted using modelling approaches. A comparison is made in the CONCAWE report between modelled predictions of bioconcentration potential in fish and reliable experimental data for algae and Daphnia species for hydrocarbons. The results show that when fish biotransformation of hydrocarbons is taken into account, this has a marked reduction in predicted BCF values. The bioaccumulation predictions were judged to be inappropriate for hydrocarbons since metabolism in the gut (which is effectively assumed in food chain model calculations) is ignored. The decision to exclude model predictions was supported by the experimental dietary BMF data demonstrating the critical role of gut metabolism in limiting biomagnification of hydrocarbons via the diet. It is concluded by CONCAWE that based on available data, mono-aromatic hydrocarbons are neither bioaccumulative nor very bioaccumulative. Similar assessments for paraffins and branched (or iso-) paraffins concluded that C13 and C14 paraffins and C12-C16 branched paraffins may be bioaccumulative but not very bioaccumulative.

Bioaccumulation studies are waived for dodecan-1-ol and tetradecan-1-ol on the basis that bioaccumulation in fish would be confounded by the technical difficulties of maintaining the test alcohols in solution. As was demonstrated in the long-term studies of effects in invertebrates, severe difficulties were encountered in conducting the study as biodegradation of structurally analogous substances in the test system was almost complete within the 24 h test media renewal period. Similarly, there is no requirement in REACH to conduct any secondary poisoning assessment in view of the lack of toxic effects in mammals. These alcohols do not fulfil the bioaccumulative or very bioaccumulative criteria.

Therefore, as the constituents (namely C9-C14 aliphatics (2-25% aromatics), dodecan-1-ol and tetradecan-1-ol) cannot be regarded as bioaccumulative in aquatic, sediment or terrestrial organisms, Alchisor TAL 145 does not fulfil the criteria “bioaccumulative (B)” or “very bioaccumulative (vB)”. According to ECHA Guidance on information requirements and chemical safety assessment (May 2008), Chapter R.11, Figure 11-2: Integrated testing strategy for B-assessment, no further testing is required to conclude on the bioaccumulation criterion.

Toxicity Assessment

Although a toxicity assessment is not required if the P and B criteria are not met (see above) it is discussed here. According to Annex XIII of Regulation (EC) No 1907/2006 and according to the Guidance on information requirements and chemical safety assessment Chapter 11 (PBT Assessment, May 2008), a substance does not fulfill the criterion if the NOEC for marine or freshwater organisms is 0.01 mg/l or higher and if there is no evidence of chronic toxicity considering human health and no classification as carcinogenic (category1 or 2), mutagenic (category 1 or 2) or toxic for reproduction (category 1, 2 or 3) according to Directive 67/548/ECC.

Constituents of Alchisor TAL 145 are not classified as carcinogenic (category 1A or 1B), germ cell mutagenic (category 1A or 1B), or toxic for reproduction (category 1A, 1B or 2) and there is no evidence of chronic toxicity, as identified by the classifications STOT (repeated exposure), category 1 (oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume) or category 2 (oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume) according to Regulation (EC) No 1272/2008.

Reliable acute and chronic aquatic toxicity data for constituents of Alchisor TAL 145 (namely C9-C14 aliphatics (2-25% aromatics), dodecan-1-ol and tetradecan-1-ol) are available for fish, invertebrates, and algae species. In a protective approach, the most sensitive study result from across the three constituents has been identified and used in this assessment. The most sensitive short-term measured results for fish, invertebrates and algae across the three substances are 1.01 mg dodecan-1-ol /L, 0.765 mg dodecan-1-ol /L and 0.33 mg dodecan-1-ol /L. Toxicity data for long-term exposure to tetradecan-1ol indicated the lowest NOEC value of 0.0016 mg tetradecan-1-ol/L for Daphnia magna reproduction. Toxicity data for long-term exposure to C9-C14 aliphatics (2-25% aromatics) to fish indicated a NOEC of 0.079 mg/L for Oncorhynchus mykiss when exposed to C11-C14. No reliable data were available for the long-term toxicity of dodecan-1-ol and tetradecan-1-ol to fish. The most sensitive long-term algae result was for exposure of Scenedesmus subspicatus to dodecan-1-ol resulting in a 72 hr NOEC of 0.085 mg/L. A predicted 48-hr NOELR for exposure of microorganisms (Tetrahymena pyriformis) to C8-C12 was 1.12 mg/L.

Reliable chronic toxicity data were not available for sediment organisms (for C9-C14 aliphatics (2-25% aromatics) and dodecan-1 -ol), soil invertebrates, plants, or soil micro-organisms, although an acute study with an LD50 of 176,000 mg/kg (food) was available for birds (Yoshida and Hoshii, 1971) indicating the substance is not toxic to avian species.

Based on available reliable data for toxicity of constituents of Alchisor TAL 145, The chronic data for tetradecanol show an NOEC <0.01 mg/L and thus meets the definitive toxicity criterion according to the ECHA guidance on PBT assessment (Part C). In a protective approach, the data for tetradecanol have been selected as the most sensitive across the Alchisor TAL 145 constituents. In light of these data, Alchisor TAL 145 does fulfill the Toxicity criteria as laid down in Annex XIII of regulation (EC) No 1907/2006.

PBT Assessment

Persistence: From a comparison of the results obtained for Alchisor TAL 145 and constituents (namely C9-C14 aliphatics (2-25% aromatics), dodecan-1-ol and tetradecan-1-ol) with the criteria of REACH Annex XIII, it can be concluded that Alchisor TAL 145 is not persistent (P) under aerobic conditions.

Bioaccumulation: The constituents (namely C9-C14 aliphatics (2-25% aromatics), dodecan-1-ol and tetradecan-1-ol) cannot be regarded as bioaccumulative in aquatic, sediment or terrestrial organisms. The data requirement for bioaccumulation studies is waived because studies are either unsuitable, as for C9-C14 aliphatics (2-25% aromatics), or technically unfeasible, as for dodecan-1-ol and tetradecan-1-ol and no reliable measured bioconcentration information is available for these constituents of Alchisor TAL 145. Evidence exists to show that predicted modelled data overestimate bioconcentration because the biotransformation of hydrocarbons and the ready biodegradation of Alchisor TAL 145 are not accounted for. Therefore, based on the criteria of REACH Annex XIII, it can be concluded that Alchisor TAL 145 is not bioaccumulative (B) or very bioaccumulative (vB).

Toxicity: Based on available reliable data for toxicity of constituents of Alchisor TAL 145, The chronic data for tetradecanol show an NOEC <0.01 mg/L and thus meets the definitive toxicity criterion according to the ECHA guidance on PBT assessment (Part C). In a protective approach, the data for tetradecanol have been selected as the most sensitive across the Alchisor TAL 145 constituents. In light of these data, Alchisor TAL 145 does fulfill the Toxicity criteria as laid down in Annex XIII of regulation (EC) No 1907/2006.

Constituents of Alchisor TAL 145 (namely C9-C14 aliphatics (2-25% aromatics), dodecan-1-ol and tetradecan-1-ol) fulfill the toxicity criteria, but not the screening criteria for persistence or bioaccumulation. The overall conclusion is that Alchisor TAL 145 does not meet the PBT or vPvB criteria. No further testing is required.