Decene, hydroformylation products, low boiling

Toxicity to aquatic algae and cyanobacteria

Description of key information

Adequate reliable measured and estimated data exists for toxicity to algae of analogue and constituent categories of Alchisor TAL 111 (namely, Alchisor TAL 123 and C9 -C14 aliphatics (2 -25% aromatics)). In accordance with the approach defined in the 'Read Across Justification' report in section 13, the most relevant and reliable study result from across the analogue/constituent categories has been identified and used to address the hazard endpoint in question.  The most relevant study result from across the analogue/constituent categories has been identified as a reliable study with Alchisor TAL 123 which reports a nominal 72-hr EL50 based on growth of 14.6 mg/L and a NOELR of 3.75 mg/L.  The NOELR value will be taken as the toxicity in aquatic algae endpoint for Alchisor TAL 111. 

Key value for chemical safety assessment

EC50 for freshwater algae:

14.6 mg/L

EC10 or NOEC for freshwater algae:

3.75 mg/L

Additional information

Alchisor TAL 111 is decene, hydroformylation product, low boiling and can be characterised as a UVCB substance. As defined in the ‘Read-Across Justification Document’ section 13, data provided for the analogue substance Alchisor TAL 123 and the Alchisor TAL 111 consitutent category substances, Category 3 hydrocarbon solvents, are representative of Alchisor TAL 111 and suitable for assessment purposes. Study data for each analogue/constituent category has been evaluated and considered together.Four reliable (Klimisch 1) short-term toxicity studies in algae have been conducted for analogue/constituent categoriesof Alchisor TAL 111 (namely, Alchisor TAL 123 and C9 -C14 aliphatics (2 -25% aromatics)), and are included in this dossier.In accordance with the approach described in thhe 'Read-Across Justification' Report in section 13, the most reliable and relevant study result from across the analogue/constituent categories is the Alchisor TAL 123 algal study (ENVIRON, 2012) and used to address the hazard endpoint in question.

Alchisor TAL 123

The freshwater algae Pseudokirchneriella subcapitata was exposed to the soluble components of alkenes, C11‐12, hydroformylation products, low boiling in an acute and chronic (72 hour) aquatic toxicity test (ENVIRON, 2012). The test material preparation was designed to specifically assess toxicity due to the water soluble components of the test compound, reducing the potential for effects due to physical (as opposed to chemical) impacts on the test organisms. The test endpoint (growth rate) was estimated using the initial mass loading of the test material, i.e., the median Effective Loading (EL50) value and NOELR. Test endpoints were expressed as the WAF of the nominal initial loading rate of the test product; a low-level total organic carbon (TOC) analysis was used for dose verification.

The estimated 72 hour P. subcapitata EL50 for the WAF of alkenes, C11‐12, hydroformylation products, low boiling (Alchisor TAL 123) is 14.6 mg/L WAF (95% confidence interval 11.7 to 30.0 mg/L WAF) as modified for water-insoluble substances. The equivalent NOELR is 3.75 mg/L (WAF).

C9-C14 Aliphatics (2-25% Aromatics)

Three reliable (Klimisch 1) toxicity study results for algae were available to represent C9-C14 aliphatics (2-25% aromatics). The Shell Research and Technology Centre (1995) conducted a GLP compliant OECD 201 study with low aromatic white spirit (identified as hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, aromatics (2-25%)) whereRaphidocelis subcapitata (new name: Pseudokirchnerella subcapitata), was exposed for 72 hrs. The 72 -hr EL50 forRaphidocelis subcapitatawas 4.6-10 mg/l (WAF) for growth and biomass. The 72-hr NOELR was 3 mg/L, based on biomass and growth. The 72-hr EL50, based on biomass and growth was estimated to be 10-100 mg/L. Exxon Biomedical Sciences, Inc (2005) conducted a GLP compliant OECD 201 study with low aromatic white spirit (identified as hydrocarbons, C9-C12, isoalkanes, cyclics, aromatics (2-25%)) wherePseudokirchnerella subcapitatawas exposed for 72 hrs. The 72-hr NOELR and NOEC, based on growth and biomass, were 0.76 and 0.16 mg/L, respectively. Biomass was more sensitive than growth measurements and resulting EL50 and EC50, based on biomass, were 2.3 and 0.53 mg/L, respectively. The Shell Research and Technology Centre (1997) conducted GLP compliant OECD 201 study with low aromatic white spirit (identified as hydrocarbons, C10-C13, C8-C12 & C9-C12, n-alkanes, isoalkanes, cyclics, aromatics (2-25%)) whereRaphidocelis subcapitata (new name: Pseudokirchnerella subcapitata) was exposed for 72 -hrs. The 72 -hr EL50 forRaphidocelis subcapitatawas 4.6-10 mg/l (WAF) for growth and biomass. The 72-hr NOEL was 0.22 mg/L, based on biomass and 1 mg/L, based on growth.  The 72-hr NOEC of 0.22 mg/L is considered the most sensitive study result for long-term toxicity ofC9-C14 aliphatics (2-25% aromatics) to algae.

 

Adequate reliable measured and estimated data exists for toxicity to algae of analogue/constituent categories of Alchisor TAL 111 (namely, Alchisor TAL 123 and C9 -C14 aliphatics (2 -25% aromatics)). The most relevant study result from across the analogue/constituent categories has been identified as a reliable study with Alchisor TAL 123 (ENVIRON, 2012) which reports a nominal 72-hr NOELR based on growth of 3.75 mg/L. This value is taken as the toxicity in aquatic algae endpoint for Alchisor TAL 111.