1,5,10-trimethylcyclododeca-1,5,9-triene, epoxidised

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

5.163 µg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.516 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.516 µg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

PNEC marine water (intermittent releases):

0.052 µg/L

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

7.5 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

2.053 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.205 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:

0.408 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

49.56 mg/kg food

Assessment factor:

90

Additional information

Aquatic toxicity:

Four valid acute experimental studies based on international guidelines are available to assess the aquatic toxicity of the registered substance.

Among all data available, toxic effects were observed on the three aquatic trophic levels (aquatic invertebrate, algae, fish), in acute conditions. The most sensitive species is the aquatic invertebrate Daphnia magna, with a 48h-EC50 value measured at 5.163 mg/L. For the zebrafish Danio rerio, the 96h-LC50 value was measured at 5.371 mg/L and for the algae Pseudokirchneriella subcapitata,the 72h-ErC50 value was measured at 20.457 mg/L. The 72h-ErC10 value was also determinated at 3.510 mg/L. In addition, the effect of the registered substance on the respiration of activated sewage sludge gave a 3h-EC10 value measured at 75 mg/L and a 3h-EC50 value greater than 1000 mg/L.

Sediment/Terrestrial toxicity and secondary poisoning:

In the absence of any ecotoxicological data for sediment-dwelling/soil organisms, the PNEC sediment/soil were calculated using the equilibrium partitioning method (EPM). Furthermore, no toxicity studies reporting the secondary poisoning effects on bird were available, therefore the combined repeat dose toxicity study and reproductive/developental toxicity screening study by dietary administration in the rat (OECD Guideline 422) was used to derive the PNECoral.

Environmental fate and pathways:

The registered substance is hydrolytically stable at pH>5 and is not readily biodegradable.In addition, the biodegradation result obtained after 60 days do not allow to conclude that the registered substance is not persistent in the environment even if, after a long period of time, the substance would ultimately biodegrade.

Based on a QSAR approach, the estimated BCF values of the registered substance well all comprised between407 and 4219 L/kg, calculated using the experimental log Kow value at 5.05. Based on these available data, the registered substance seems to be bioaccumulable (log Kow > 4.5 and BCF > 2000 L/kg) but not very bioaccumulable (BCF < 5000 L/kg) according to PBT criteria. However, at pH in the stomach of fish (generally comprised between 2 and 4), hydrolysis of the registered substance occured before biotransformation in liver. Indeed, in acidic conditions and up to pH 5, the registered substance is unstable and will hydrolyze to give poly-hydroxylated product. The BCF value of this hydrolysis product / metabolite at acid pH (the diol form) is considerably low, at 12.9 L/kg. Therefore, we can conclude that the registered substance is not bioaccumulable.

Finally,the adsorption coefficient of the registered substance has been evaluated to be in the range of 150 to 3940, corresponding to a log Koc comprised between 2.18 and 3.60. Thisresult indicates that the registered substance has a medium to slightly mobility in soils (according to P.J. McCall et al., 1981).

Conclusion on classification

No harmonised classification is available on the registered substance.

The aquatic invertebrate Daphnia magna is the most sensitive species with a 48h-EC50 at 5.163 mg/L.

1 mg/L < lowest EC50 value < 10 mg/L ; EC10 algae > 1 mg/L; the substance is not readily biodegradable and has a log Kow of 5.05 (> 4).

Classification according to the Annex VI of the Regulation (EC) No 1272/2008 (CLP) : The registered substance is classified as Aquatic Chronic Category 2 for the environment.