Alkenes, C11-12, hydroformylation products, distn. residues

Bioaccumulation: terrestrial

Description of key information

Alchisor CAL 123 comprises alkenes C11-12, hydroformylation products, distillation residues.  In accordance with REACH Annex IX, the requirement for a bioaccumulation study is waived on the basis of ready biodegradability, low toxicity to aquatic organisms and the absence of toxicity to mammals as it is considered unlikely to cause secondary poisoning in higher organisms.  No reliable measured bioconcentration information is available for Alchisor CAL 123.

Additional information

Alchisor CAL 123 comprises alkenes C11-12, hydroformylation products, distillation residues and where environmental toxicity data exist, these are representative of the Alchisor CAL 123 substance. The REACH requirement in Annex IX for a study on the bioaccumulation in aquatic species is not needed if the substance has a low potential for bioaccumulation and/or a low potential to cross biological membranes.

The log Kow of Alchisor CAL 123 is presented as a range between 3.79 to >7.87 (with an average weighted mean value of 7.71), however it considered that secondary poisoning is unlikely to occur and the data requirement for CAL 123 is waived on the basis of ready biodegradability, low toxicity to aquatic organisms and the absence of toxicity to mammals. No reliable measured bioconcentration information is available for Alchisor CAL 123.

Biodegradation

Alchisor CAL 123 has been shown in the reliable (Klimisch 1) study by Schaefer and Matthews (2010) to be readily biodegradable in water. The test substance biodegraded to an extent of 87.7% after 28 days and although the biodegradation rate just missed the 10-day window threshold, this aspect of the test is not applicable to mixtures where different components of the mixture can biodegrade preferentially (reference TG 103C). It is assumed that Alchisor CAL 123 will readily biodegrade in the environment and be unavailable for uptake and bioaccumulation in biological organisms.

Toxicity to Aquatic Organisms

The toxicity of the test substance to aquatic organisms is very low based on the evidence presented in this dossier. The lowest measured toxicity was based on an algal test where the NOEL based on algal growth was 25 mg/L. Acute toxicity to invertebrates and fish was >100 mg/L based on 50% mortality. It is reasonable to assume that a similar trend will be seen in soil organisms where Alchisor CAL 123 represents a low hazard and is not considered to be toxic (in PBT terms) to terrestrial life.

Toxicity to Mammals

Alchisor CAL 123 is not considered to be toxic to mammals based on the evidence presented in this dossier. Acute oral and acute dermal toxicities in rat were > 2000 and >2020 mg/kg, respectively based on the study by Kuhn (2010). Using this evidence it is assumed that Alchisor CAL 123 is not considered to be toxic (in PBT terms) to mammals and secondary poisoning is unlikely to occur in the environment.

In summary, the data requirement for bioaccumulation in aquatic and terrestrial organisms is waived on the evidence of ready biodegradability and the absence of toxicity in aquatic organisms and mammals.