Grapefruit, ext.

Endpoint summary

Description of key information

Substance characterisation

The test substance Grapefruit oil is a Natural Complex Substance (NCS) which is a subgroup of Complex reaction products or Biological material (UVCB substances). With 97% of the constituents composition of Grapefruit oil known, this NCS can be considered as a well defined NCS. The constituents of Grapefruit oil are predominantly alicyclic unsaturated monoterpene hydrocarbons. Other constituents are aliphatic short-chain aldehydes, ketones and alcohols, with one or more double bonds. In the typical Grapefruit oil, the main constituent limonene is present at 88% of the composition.

 

The composition with limonene and some minor terpenoid constituents represents a relatively homogenous type of NCS. The environmental risk assessment will be based on the properties of the main constituent limonene. This constituent was identified using the so-called DPD+ approach.

In spite of the structural similarities of many constituents, the ranges for water solubility, volatility, adsorption and lipophility are considerable and thus the environmental behaviour of the constituents may vary. Due to these differences the assessment of these environmental propertiesof Grapefruit oil is based on data for the individual constituents.

 

Based on the constituent approach as described in the industry protocol for the REACH registration of NCSs of botanical origin used as fragrance ingredients (see footnote 1), Grapefruit oil is to be considered as a readily biodegradable substance. The water solubility ranges from 0.5 to 1100 mg/l for the constituents. The water solubility is > 10 mg/l for 94% of the constituent composition including the main constituent limonene. One constituent present in 1% of the composition has an estimated water solubility of 0.5 mg/l.

 

The log Kow of the constituents is below 4.5 for typically 93% of the constituent composition, whereas only one of the constituents (1%) has a log Kow below 3. With log Kow 4.38, limonene represents the group with a relatively high log Kow (Koc of limonene estimated at 2413). Log Kow is above 4.0 for 92% of the constituent composition. 

Most constituents may have a tendency to sorb to organic matter. As the NCS is considered to be biodegradable, adsorption/desorption studies were waived.

 

The estimated vapour pressure of Grapefruit oil was 195.4 Pa, ranging from 0.164 to 981 Pa for the constituents. For Limonene (typically 88%) the vapour pressure is 193 Pa and another 4% of the constituents composition has a higher vapour pressure. This indicates that partitioning by volatilisation will be significant.

 

Classification and PBT assessment

Although Grapefruit oil is considered readily biodegradable, log Kow is >4 for typically 92% of the constituent composition. As there is no empirical BCF for Grapefruit oil or for its main constituent limonene at the moment, a classification for long-term effects in the environment is applied as a worst case for both the classification according to Directive 67/548/EEC (DSD) and according to Regulation 1272/2008/EC (CLP).

Based on its ready biodegradability, Grapefruit oil does not fulfill the PBT-criteria for Persistent. As typically 93% of the constituent composition has a log Kow <4.5, Grapefruit oil is also not considered bioaccumulative. Grapefruit Oil is not to be considered as a PBT substance.

 

(1) A statement on the use of the protocol for Registration of Natural Complex Substance (NCS) under REACH has been attached to the dossier