Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Patchouli ext. is a mixture of sesquiterpene alcohols and sesquiterpene hydrocarbons, the latter of which can be subdivided into lower and higher boiling sesquiterpenes. The three blocks of related constituents have different adsorption potential as indicated by the measured log Koc values: 3.63, 4.58 and 4.63. The higher adsorption potential of the sesquiterpene hydrocarbons indicates that soil and sediment are likely to be the main target compartments for exposure assessment for these constituents. Although Patchouli ext. is not directly exposed to soil, there is potential for indirect exposure to adsorptive components via the practise of fertilising soil with sludge from a STP. Therefore, the effect of sesquiterpene hydrocarbons on soil organisms was assessed. Enriched fractions of alpha-guaiene and alpha-bulnesene were isolated by fractional distillation of Patchouli Oil and an acute toxicity test to earthworms conducted. The LC50 values were used to derive PNECsoil for the lower and higher boiling sesquiterpene hydrocarbon blocks.

The sesquiterpene alcohols belong to soil hazard category 1 (REACH guidance, Table R.7.11 -2). Represented by patchouli alcohol, they are considered not highly adsorptive (estimated log Kow < 5), not persistent and not very toxic to aquatic organisms (EC/LC50 is equal to or greater than 1mg/l). Thus, in accordance with REACH guidance R.7C the Equilibrium Partitioning Method was applied to derive PNECsoil for Patchouli alcohol.

As the exposure assessment does not indicate risk for the terrestrial compartment, further studies on terrestrial organisms are waived.