Hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, <5% n-hexane

Endpoint summary

Description of key information

There is data available for this substance. Additionally, key, and supporting data is available for structural analogues. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

The substances are poorly soluble and made of constituents with various water solubility. As a consequence, the exposures were performed with Water Accommodated Fractions (WAFs). Therefore, the results are based on nominal loadings.

Based on data available for this substance and structural analogues, this substance does demonstrate acute fish, acute invertebrate, algae and microorganism toxicity at high loading rates.

According to the harmonised CLP legislation (2008), Annex VI, this substance is classified for the environment as aquatic chronic category 2 with the hazard statement H411: Toxic to aquatic life with long lasting effects.

Additional information

Key and information is summarised below:

Short-term toxicity to fish

There is data available for this substance. Additionally, key and supporting data is available for structural analogues Hydrocarbons C7, n-alkanes, isoalkanes, cyclics; Hydrocarbons C7-C9, isoalkanes; Hydrocarbons C7-C9, n-alkanes, isoalkanes, cyclics. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13. Key information is summarised below:

The test substance hydrocarbons, C7, n-alkanes, isoalkanes, cyclics, exhibited a 96-hour LL50 value of >13.4 mg/L with rainbow trout (Oncorhynchus mykiss).

The test substance, hydrocarbons, C7-C9, isoalkanes produced acute lethal toxicity to Oncorhynchus mykiss at 18.4 mg/L, based on nominal loading of the test substance in water.

The test substance, hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, < 5% hexane, produced acute lethal toxicity to Oncorhynchus mykiss at 11.4 mg/L, based on nominal loading of the test substance in water.

The test substance, hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics exhibited a 96-hour LL50 value for fish of 3-10 mg/L WAF.

Long-term toxicity to fish

The aquatic toxicity was estimated using the PETROTOX computer model (v4.0), which combines a partitioning model used to calculate the aqueous concentration of hydrocarbon components as a function of substance loading with the Target Lipid Model used to calculate acute and chronic toxicity of nonpolar narcotic chemicals. PETROTOX computes toxicity based on the summation of the aqueous-phase concentrations of hydrocarbon block(s) that represent a hydrocarbon substance and membrane-water partitioning coefficients (KMW) that describe the partitioning of the hydrocarbons between the water and organism.

Short-term toxicity to aquatic invertebrates

There is data available for this substance. Additionally, key and supporting data is available for structural analogues Hydrocarbons C7-C9, n-alkanes, isoalkanes, cyclics. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13. Key information is summarised below:

The test substance hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics exhibited a 48-hr EL50 for 4.6-10 mg/L WAF for Daphnia magna.

 

The test substance, hydrocarbons, C6 -C7, n-alkanes, isoalkanes, cyclics, < 5% hexane, exhibited 48-hr EL50 of 3.0 mg/L (WAF) for Daphnia magna.

 

Long-term toxicity to aquatic invertebrates

There is no data available for this substance. However, key, data is available for structural analogue hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics.The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13. Key information is summarised below:

The test substance hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics exhibited an NOELR and an EL50 (based on growth and reproduction) of 1 and 1.6 mg/L (WAF), respectively.

Toxicity to algae and cyanobacteria

There is data available for this substance. Additionally, key and supporting data is available for structural analogue Hydrocarbons C7-C9, n-alkanes, isoalkanes, cyclics. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13. Key information is summarised below:

In one study. the test substance, hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics, produced a significant effect on green algae biomass at 13 mg/L, based on nominal loading of the test substance in water.

In a second study, the test substance hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics exhibited a 72-hr EbL50 for algae of 10 -30 mg/L (WAF), and the 72-hr ErL50 of 10-30 mg/L (WAF). The 72-hr NOEL value for algal biomass and growth rate was 10 mg/L.

The test substance, hydrocarbons, C6-C7, n-alkanes, isoalkanes, cyclics, <5% n-hexane, produced a significant effect on algal biomass at 10 to 30 mg/L, and on growth rate at 30 to 100 mg/L, based on nominal loading of the test substance in water. NOELs for growth and biomass were determined to be 3 mg/L.

Toxicity to microorganisms

The aquatic toxicity was estimated using the PETROTOX computer model (v4.0), which combines a partitioning model used to calculate the aqueous concentration of hydrocarbon components as a function of substance loading with the Target Lipid Model used to calculate acute and chronic toxicity of nonpolar narcotic chemicals. PETROTOX computes toxicity based on the summation of the aqueous-phase concentrations of hydrocarbon block(s) that represent a hydrocarbon substance and membrane-water partitioning coefficients (KMW) that describe the partitioning of the hydrocarbons between the water and organism.