Heptane

Ecotoxicological Summary

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Additional information

The ecotoxicity of Normal-Heptane has been examined in a series of studies on fish, Daphnia and algae, and additional QSAR modelling has been performed. The most conservative results of aquatic studies are: EL50 of 2.1 mg/L (Daphnia, measured), LL50 of 5.7 mg/L (fish, estimated), and 4.34 mg/L (algae, estimated). Studies were conducted in Water Accommodated Fraction (WAF) studies because of the limited water solubility. QSAR modelling data on microorganisms resulted in an EL50 of 22 mg/L. One study in the category is available on chronic aquatic toxicity for Daphnia with a NOELR of 1 mg/L. QSAR modelling was performed to further address chronic toxicity of Normal-Heptane and NOELRs were in the range of 0.97-1.2 mg/L for algae and fish. For the purpose of risk assessment, soil PNECs for hydrocarbon blocks have been derived using aquatic PNECs and the equilibrium partitioning method (EqP) using representative structures. The assessment indicated no risk to the environment. Studies on long-term or reproductive toxicity to birds do not need to be conducted due to the existence of a large mammalian dataset demonstrating low toxicity to higher organisms.

Conclusion on classification

The substance is readily biodegradable. The most sensitive acute aquatic values are an EL50 of 3.9 mg/L (Daphnia, freshwater) and LL50 of 2.1 mg/L (Mysidopsis, saltwater). A BCF is estimated to be 552 and the log Kow is 4.5 according to handbook data. Measured and estimated chronic values for all three trophic levels are in the range of 0.97-1.2 mg/L.

The substance is classified R50/53 according to DSD/DPD based on listing on Annex I and classified aquatic acute category 1 and aquatic chronic category 1 according to harmonised classification acc. to Annex VI (CLP).