(R)-p-mentha-1,8-diene

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

14 µg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

1.4 µg/L

Assessment factor:

100

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

1.8 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

3.85 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.385 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:

0.763 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

133 mg/kg food

Assessment factor:

30

Additional information

The PNEC values were determined for the substance itself by application of methods provided in ECHA Guidance Chapter R.10 (May 2008). Since the dataset covers each of the three trophic levels on the sort-term and the long-term, the preference was given to apply a standard assessment factor on EC10 for long-term endpoint.

Conclusion on classification

d-Limonene is slightly soluble in water (column elution method: 3.69 mg/L; slow-stirring method: 5.69 mg/L). The following toxicity values are available for the substance.

Aquatic acute toxicity

Fish: Experimental data on Pimephales promelas: 96h-LC50 = 0.720 mg/L (meas.) ; 96h-LC50 = 0.702 mg/L (meas.)

QSAR estimation based on Mode of Action 1: 96h-LC50= 0.46 mg/L

Aquatic invertebrates: Daphnia magna: 48h-EC50 = 0.307 mg/L (meas.); 48h-LC50 = 0.924 mg/L (meas.); 48h-EC50 = 0.421 mg/L (meas.); 48h-EC50 = 0.36 mg/L (nom.); 48h-EC50 = 0.51 mg/L (meas.)

QSAR estimation based on Mode of Action 1: 48h-EC50= 0.62 mg/L

Algae: Pseudokirchneriella subcapitata: 72h-EC50= 0.32 mg/L (meas.) ; 48h-EC50= 0.25 mg/L (meas.)

QSAR estimation based on Mode of Action 1: 72h-EC50= 0.50 mg/L

Based on available data, the lowest acute aquatic toxicity values range between 0.1 and 1.0 mg/L.

CLP self-classification for environment Acute aquatic hazard: Category 1. M-Factor: 1. Reasoning: lowest E(L) C50 between 0.1 and 1.0 mg/L.

Biodegradation: D-limonene was found to be readily biodegradable.

Aquatic Chronic toxicity

The proposal is based on a weight of evidence approach taking into account the positives and negatives of the experimental long-term studies: Negatives

The fish study is an OECD 212 8 day study and is not an OECD 210 which is believed the preferred test method for long-term toxicity to fish under REACh.

The 8 day fish study and the daphnid 21 day study endpoint values were based on measured concentrations in an abiotic group run parallel to the test as it was not possible to acquire meaningful results by sampling directly from the beakers containing daphnids. Thus the results acquired of measured concentrations may be slightly higher than the “true” concentrations to which the daphnids were exposed.

Positives

The difference between the measured NOECs and the LOECs of the fish 8 day and daphnid chronic studies straddle the classification threshold. As NOECs depend on a subjective choice of nominal concentration with little relationship to an actual no effect concentration, as the geometric mean (MATC) of the NOECs and LOECs of both studies fall greater than 0.1 mg/L suggesting that the “true” effect concentration may be higher than the classification threshold and as the EC10s are all greater than 0.1, there are good reasons for considering the EC10 to be the value used for classification rather than the NOEC.

There is strong evidence that limonene is a highly volatile, readily biodegradable, Mode of Action 1 chemical and as such is not expected to be of serious concern to any environmental compartment.

The proposal is based on the use of the long-term EC10.

Fish: Experimental data on Pimephales promelas: 8d-EC10 between 0.37 and 0.67 mg/L

Aquatic invertebrates: Daphnia magna: 21d-EC10 reproduction = 0.153 mg/L

Algae:

Pseudokirchneriella subcapitata: 72h-EC10= 0.174 mg/L (meas.); 48h-EC10 growth rate = 0.14 mg/L

CLP self-classification for environment Category 3. M-Factor: Not applicable. Reasoning: adequate chronic toxicity data are available, lowest acute E(L)C10 value range between 0.1 and 1.0 mg/L, readily degradable substance.