1,3-bis[12-hydroxy-octadecamide-N-methylene]-benzene

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.004 mg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.045 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0 mg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

10 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

11.32 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

1.132 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

2.25 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

27.78 mg/kg food

Assessment factor:

90

Additional information

Aquatic PNECs have been derived as described above based on the results acute toxicity testing in fish, daphnia and algal. However, these PNECs are considered to be of limited reliability.

All acute testing showed no effects up to the limit of the substances solubility (0.64 mg/l). However, test solutions were able to be prepared well in excess of the water solubility (nominal concentrations up to 100 mg/l). The acute testing showed LC50/EC50 for fish and algae to exceed the nominal concentration of 100 mg/l (corresponding to a measured concentration of 55 mg/l and 71 mg/l respectively). Acute testing in Daphnia showed EC50 to exceed a nominal concentration of 4.5 mg/l, which has been taken as the EC50 result for PNEC derivation. However, as the EC50 was greater than 4.5 mg/l, the subsequent PNEC is also a 'greater than' value and therefore must be treated with caution.

The subsequent PNECs for sediment and soil should therefore also be treated with caution as they are based on the aquatic PNECs.

An assessment of aquatic PNEC was therefore also made based on water solubility alone. If the PNEC is taken as 1/100th of water solubility, it would result in an aquatic PNEC of 0.0064, which is in line with the PNECs based on acute testing data.

However, as no effects were seen at the limit of solubility it is considered that the PNECs are of limited reliability in assessing the substances risk to the environment and that in reality the PNEC is above water solubility.

In addition, as the substance is a UVCB any potential toxicity (if seen in acute testing) could not be attributed to a single component but to the test item as a whole.Therefore, PNECs derived from studies conducted on complex substance, with a mix of poorly soluble components, should be treated with caution as differences between components in partitioning in the environment could make comparison of a single PNEC to PEC unreliable.

As the substance is not readily biodegradable and has limited bioaccumulation potential, an assessment of possible long-term exposure effects is required, although the derived PNECs may not be reliable for this purpose.

Conclusion on classification

The substance is classified for the environment under CLP as Chronic Category 4 (H413: May cause long lasting harmful effects to aquatic life), based on the following information.

In acute toxicity testing (on a comparable structural analogue) in fish, daphnia and algae, no toxicity was recorded up at levels up to the water solubility of the tested substance. The EC/LC50 values were well beyond the substances water solubility.

The substance is not readily biodegradable and has a log Kow >6.5.

For poorly soluble substances for which no acute toxicity is recorded at levels up to the water solubility and which are not readily biodegradable and have a log Kow >4, a classification of Chronic Category 4 is appropriate.

The acute algal study, which can also be considered as providing a chronic endpoint, gave a NOEC of 10 mg/l. For chronic toxicity data where the NOEC is greater than water solubility or 1 mg/l, the category 4 classification may not apply. However, in this case as the 'chronic' endpoint comes from a 72 -hr algal study it is considered appropriate to maintain the Category 4 classification.