No IUPAC name is currently defined for Cashew (Anacardium occidentale) Nutshell Extract, Decarboxylated (Technical Grade).

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Justification for type of information:

The effect values for the long-term toxicity to invertebrates endpoint for the target substance Technical Grade have been generated by interpolation from the experimental test data on the source substances Distilled Grade (EC Number 700-991-6) and Distillation Residue Grade (EC Number 941-212-1). In this context interpolation is considered to be the ‘estimation of a value for a member of the group using measured values from other members on both sides of that member within the defined group spectrum’ (ECHA 2008: Guidance on information requirements and chemical safety assessment. Chapter R.6: QSARs and grouping of chemicals).

Distilled and Distillation Residue Grades represent the two ends of the compositional spectrum of the three grades of CNSL with regard to the levels of the main component (the different forms of cardanol) and the polymeric content. Distilled Grade has the highest level of cardanol and a lowest level of polymeric content, whilst Distillation Residue Grade has the lowest level of cardanol and the highest level of the polymeric content. On a compositional basis the target substance Technical Grade lies between Distilled and Distillation Residue Grade.

Full details of the results of the OECD TG211 tests on Distilled Grade and Distillation Residue Grade are given in the relevant Registration Dossiers

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: No significant effects on any of the measured parameters for parental daphnids and offspring at any of the WSFs including the highest concentration of 10 mg/L

Details on results:

- Behavioural abnormalities: An absence of behavioural abnormalities is expected for organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade.
- Observations on body length and weight: No statistically significant reduction of growth (based on the length of individuals at the end of the study) in the test concentrations (compared to the controls) is expected for organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade.
- Other biological observations: It is expected that eggs will be present in the brood pouch for the first time on day 4-5 and the first brood will appear on day 8 in organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade. It is also expected based on the available data that on average the first recording of young would be similar to the control in all the test concentrations. Furthermore, it is expected that statistical analysis would show that the reproduction of the daphnids was not significantly different from the control group at any of the test concentrations (from 1 to 10 mg/l loading rate) in a test on Technical Grade
- Mortality of control: No statistically significant changes of parental mortality (immobility) in the test concentrations (compared to the controls) is expected for organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade.
- Other adverse effects control:
- Immobilisation of control: An immobilisation rate of <20% is expected for control organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade.
- Abnormal responses: An absence of abnormal responses is expected for organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: None
- Effect concentrations exceeding solubility of substance in test medium: The interpolated 21-day NOEC of 10 mg/l for loading rate was above the solubility limit of the UVCB in water (0.205 mg/l) based on nominal levels, but was corrected based on the measured data for the three forms of cardanol (triene, diene and monoene) in the tests on the source substances.

Results with reference substance (positive control):

- Results with reference substance valid? No positive control used
- Relevant effect levels: No data
- Other: Not relevant

Reported statistics and error estimates:

The NOEC values for the source substances were calculated using appropriate statistical procedures that are described in detail in the relevant Registration Dossiers. On the basis of analytical data the NOEC for Technical Grade lies between 67.9 (for Distillation Residue Grade) and 113.5 µg/l (for Distilled Grade) with the lower value of 67.9 µg/l representing the precautionary “worst-case” (see Table 1). The interpolated value based on the cardanol content in the two source substances has been obtained using the following equation:

NOEC for Technical Grade = NOEC for Distilled Grade - (NOEC for Distilled Grade – NOEC for Distillation Residue Grade x 22a/48b)

where:
a = Difference between the cardanol content of Distilled and Technical Grades = 83% – 61% = 22%
b = Difference between the cardanol content of Distilled and Distillation Residue Grades = 83% - 35% = 48%

Table 1          Summary of the NOECs for Distilled and Distillation Residue Grade generated in the OECD TG211 tests and the interpolated value for Technical Grade

 

NOEC values for different substances in the OECD TG211 tests
Distilled Grade (Source substance)	Distillation Residue Grade (Source substance)	Technical Grade (Target substance)
10 mg/l (Experimental value based on nominal loading rate data)   113.5 µg/l (Experimental value based on measured concentration data)	10 mg/l (Experimental value based on nominal loading rate data)   67.9 µg/l (Experimental value based on measured concentration data)	10 mg/l (Interpolated value based on nominal loading rate data)   67.9 µg/l Worst casevalue based on measured concentration data   92.6 µg/l (Interpolated value based on measured concentration data)

Validity criteria fulfilled:

yes

Conclusions:

The effects values for the long-term toxicity to invertebrates endpoint for the target substance Technical Grade have been generated by interpolation from the experimental test data on the source substances Distilled and Distillation Residue Grades. Based on the tests on the source substances it is expected that there would be no statistically significant effects of test substance exposure on the parental mortality (immobility), reproduction (offspring per surviving daphnid) and growth (as mean body length) endpoints in any test concentrations from 1 to 10 mg/l for organisms exposed to Technical Grade. The resulting No Observed Effect Concentrations (based on loading rate) for both tests was a nominal concentration of 10 mg/l, which was interpolated to the target substance Technical Grade. On the basis of the measured analytical data for the different forms of cardanol (triene, diene and monoene) in the tests on the source substance the NOEC for Technical Grade lies between 67.9 µg/l (for Distillation Residue Grade) and 113.5 µg/l (for Distilled Grade) with the lower value of 67.9 µg/l representing the precautionary “worst-case”. The NOEC for Technical Grade based on measured concentration data has been estimated to be 92.6 µg/l.

Executive summary:

The effect values for the long-term toxicity to invertebrates endpoint for the target substance Technical Grade have been generated by interpolation from the experimental test data on the source substances Distilled and Distillation Residue Grades. In this context interpolation is considered to be the ‘estimation of a value for a member of the group using measured values from other members on both sides of that member within the defined group spectrum’ (ECHA 2008: Guidance on information requirements and chemical safety assessment. Chapter R.6: QSARs and grouping of chemicals). Distilled and Distillation Residue Grades represent the two ends of the compositional spectrum of the three grades of CNSL with regard to the levels of the main component (the different forms of cardanol) and the polymeric content. Distilled Grade has the highest level of cardanol and a lowest level of polymeric content, whilst Distillation Residue Grade has the lowest level of cardanol and the highest level of the polymeric content. On a compositional basis the target substance Technical Grade lies between Distilled and Distillation Residue Grade.

 

In the valid (Reliable without restriction, Klimisch Code 1) OECD TG211Daphnia magnaReproduction studies on Distilled and Distillation Residue Grades the test organisms were exposed to aqueous solutions containing the test substance at loading rates of 1.0, 1.8, 3.2, 5.6 and 10 mg/l prepared as Water Soluble Fractions (WSFs). The measured endpoints were the time of the first production of young, the number of young born, parental mortality (immobility) and growth and other signs of intoxication. The data for test substance exposed organisms were compared with corresponding information for the control organisms.

 

In both experimental studies on the source substances Distilled and Distillation Residue Grade the No Observed Effect Concentration NOEC (based on loading rate) was a nominal concentration of 10 mg/l for both the parental mortality (immobility), reproduction (offspring per surviving daphnid) and growth (as mean body length) endpoints .Since the results obtained for Distilled and Distillation Residue Grades were the same for the “Aquatic toxicity - Long-term toxicity testing on invertebrates endpoint” (namely a NOEC of 10 mg/l based on loading rate) this value has been estimated for the target substance Technical Grade.

 

The interpolated 21-day NOEC of 10 mg/l for loading rate was above the solubility limit of the UVCB in water (0.205 mg/l) based on nominal levels, but was corrected based on the measured data for the three forms of cardanol (triene, diene and monoene) in the tests on the source substances. On the basis of the measured analytical data for the different forms of cardanol in the tests on the source substance the NOEC for Technical Grade lies between 67.9 (for Distillation Residue Grade) and 113.5 µg/l, (for Distilled Grade) with the lower value of 67.9 µg/l representing the precautionary “worst-case”. The NOEC for Technical Grade based on measured concentration data has been estimated to be 92.6 µg/l.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

NOEC

Effect concentration:

92.6 µg/L