Lemon, ext.

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

5.4 µg/L

Assessment factor:

50

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

5.77 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.54 µg/L

Assessment factor:

500

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

2.1 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

1.3 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.13 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:

0.29 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential to cause toxic effects if accumulated (in higher organisms) via the food chain

Additional information

Lemon oil is a natural complex substance consisting of a mixture of poorly soluble constituents.

For Lemon oil, no studies on the aquatic toxicity are available for fish and algae. For Daphnia, one study is available that is rated with Reliability 3 and is used as supporting study. Thus, for all endpoints, read-across is conducted from the citrus oils Orange oil, Mandarin oil and Lime oil. The justification of this read-across is described in detail in the read-across justification document.

The aquatic toxicity for fish, Daphnia and algae was determined in tests with Water Accomodated Fractions. For algae, read across was conducted to mandarin oil (72h ErL50 = 9.7 mg/L). For Daphnia and fish read across was conducted to Orange oil. For Daphnia the 48h-EL50 is 1.1 mg/L and for fish the 96h-EL50 is 5.65 mg/L.

Lemon Oil is a complex mixture with limonene as the major constituent. A DPD+ analysis (ref 1) for Lemon Oil identified D-limonene to represent the dominant risk to the environment (see table). The ratio calculated from the constituent concentration and concentration limit is called Lead Substance Indicator (LSI). Thus the PNEC for D-limonene will be used for the risk characterization and the exposure assessment will also be carried out using limonene. PNEC values for limonene are publicly available on the ECHA website (CAS no 5989 -27 -5).

 

CAS	Substance	Conc. in lemon oil (% in typical)	R-phrase(s)	Conc. limit	LSI
5989-27-5	D-Limonene	60	R50/53	0.25	240

 

(1) REACH: Exposure scenarios for preparations. Methodology for the identification of substances that represent the dominant risks to human health and/or the environment and the drivers for risk management measures, CEFIC, June 09: final for publication

All constituents have the same working mechanism (Narcosis and Polar narcosis) and there are no minor constituents that are highly toxic to the environment. In view of the fate and behaviour and risk assessment Limonene, as the major constituent, can be taken as representative for the other constituents.  

Conclusion on classification

For Lemon oil, the lowest ecotoxicity value is a 48h-EL50 from a Daphnia study. In this study the 48h-EL50 is 1.1 mg/L. This leads to a classification with R51.

Lemon oil was shown to be readily biodegradable.

All constituents of Lemon oil have an estimated log Kow >3 (log Kow > 4 for over 90% of composition) and no measured data on BCF is available for Lemon oil, it is also classified as R53.

Thus according to Directive 67/548/EEC Lemon oil is classified as R51/53 (Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment).

According to Regulation 1272/2008/EC (CLP) Lemon oil is not classified for its acute aquatic toxicity.

Based on the 48h-EL50 for Daphnia between 1 mg/l and 10 mg/l, and its estimated log Kow > 4 it is classified as hazardous to the aquatic environment Chronic Category 2 (H411).