(3aα,4β,7β,7aα)-octahydro-4,7-methano-1H-indene

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.87 µg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

8.7 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.087 µg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

PNEC marine water (intermittent releases):

0.87 µg/L

STP

Hazard assessment conclusion:

no hazard identified

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

0.366 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.037 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:

0.073 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

1 000 mg/kg food

Assessment factor:

300

Additional information

Environmental fate and pathways

The registered substance is considered as not readily biodegradable after 28 (OECD 301D and 310) and 60 days (OECD 301D). The substance can be considered as potentially Persistent (P) or very Persistent (vP) in the environment.

Also, the registered substance has a log Kow value at 4.8, the substance is considered as potentially bioaccumulative according to CLP (> 4.0) and PBT criteria (> 4.5).

Aquatic toxicity

Three reliable QSAR results are available to assess the short-term toxicity of tetrahydrodicyclopentadiene (THDCPD) to aquatic invertebrates, algae and fish.The QSAR predictions (iSafeRat holistic approach v1.7 and v1.8) have been validated to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predict the ecotoxicological values which would be expected when testing the substance under experimental conditions in a laboratory following OECD Guidelines. The ecotoxicological predictions were determined using a validated QSAR for the Mode of Action in question, (MOA 1,as,defined by Verhaar et al (1992), or MechoA 1.1 (Bauer et al., 2018): non-polar narcosis). This QSAR is based on validated data for training sets for which the concentrations of the test substance had been determined by chemical analyses over the test period. According to these predictions, ecotoxicological data are the following:

- aquatic invertebrates: 48h-EC50 based on mobility was determined to be 1.0 mg/L (95% CL: 0.37 - 2.87 mg/L),

- algae: 72-h ErC50 based on growth rate was determined to be 0.92 mg/L (95% CL: 0.29 - 2.87 mg/L),

- fish: 96-h LC50 based on mortality was determined to be 0.87 mg/L (95% CL: 0.26 - 2.9 mg/L),

To assess the toxicity to microorganisms, one QSAR study is available on the registered substance wih a 30-180 min EC50 of THDCPD to activated sludge greater than the water solubility value within the exposure period of the test.

The substance falls within the applicability domain of the model.

Bauer F., Thomas, P., Fouchard S., Neunlist S., 2018. High-accuracy prediction of mechanisms of action using structural alerts. Computational Toxicology 7:36 -45

Conclusion on classification

For environment, tetrahydrodicyclopentadiene has no harmonised classification.

0.1 < lowest E(L)C50 value < 1 mg/L; not readily biodegradable; logKow=4.8.

Classification according to the criteria of Annex I of the Regulation (EC) No 1272/2008 (CLP): the registered substance should be classified as Aquatic Acute 1 and Aquatic Chronic 1 for the environment.