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

Sediment toxicity

Link to relevant study record(s)

Reference

Endpoint:

sediment toxicity: long-term

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 the 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 TG218 tests on Distilled Grade and Distillation Residue Grade are given in the relevant Registration Dossiers.

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

500 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: No significant effects on of test substance exposure on emergence ratio for organisms exposed at concentrations of 62.5 to 500 mg/kg d.w.

Details on results:

- Mortality of test animals at end of exposure period: Chironomids that did not emerge during tests are considered to have died.
- Total mass of test animals at beginning of test: No data available
- Changes in body weight of live adults (% of initial weight) at end of exposure period: No data available
- No. of offspring produced: No data available
- No. of emerged male and female midges (per vessel and per day): No statistically significant effect on the sex ratio of the emerged chironomids 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.
- No. of pupae failing to emerge (per vessel and per day): No (dead) pupae and no eggs masses at the end of the test are expected for organisms exposed to Technical Grade based on interpolation from the results of tests on the source substances Distilled and Distillation Residue Grade.
- Percent emergence per replicate and test concentration: No statistically significant difference in emergence ratio (ER) between the pooled control and the nominal test concentrations up to and including 500 mg/kg d.w. 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.
- Mean development rate of fully emerged midges (per replicate and treatment rate; male and female midges pooled): No statistically significant difference in mean development rate (DR) between the pooled control and the nominal test concentrations up to and including 1000 mg/kg d.w. 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.
- Mean individual dry weight of larvae (per larvae and per instar): No data available
- Number of living worms per replicate: No data available
- Number of dead worms per replicate: No data available
- Total biomass per replicate: No data available
- Morphological abnormalities: No data available
- 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.
- Other biological observations: No further observations
- Results with reference substance valid? Yes, tests were carried out during the period that the studies on Distilled and Distillation residue Grade were conducted
- Relevant effect levels: Groups of chironomids were exposed for a period of 28 days to K2Cr2O7 (Potassium dichromate) concentrations of 5.6, 10, 18, 32 and 56 mg/L and to a control
- Limit test: No
- Dose-response test: Yes
- ECx: The 28-day EC50 for emergence ratio was 21 mg/L (95% Confidence Limits = 16 to 28 mg/L) whilst the 28-day EC50 for development rate was 27 mg/L (95% Confidence Limits = 20 to 35 mg/L)
- Other: The result of the reference substance study would be expected to be of the same order of magnitude as the earlier studies.

Results with reference substance (positive control):

- Results with reference substance valid? Yes, tests were carried out during the period that the studies on Distilled and Distillation residue Grade were conducted
- Relevant effect levels: Groups of chironomids were exposed for a period of 28 days to K2Cr2O7 (Potassium dichromate) concentrations of 5.6, 10, 18, 32 and 56 mg/L and to a control
- Limit test: No
- Dose-response test: Yes
- ECx: The 28-day EC50 for emergence ratio was 21 mg/L (95% Confidence Limits = 16 to 28 mg/L) whilst the 28-day EC50 for development rate was 27 mg/L (95% Confidence Limits = 20 to 35 mg/L)
- Other: The result of the reference substance study would be expected to be of the same order of magnitude as the earlier studies.

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. Since both studies reported a NOEC of 500 mg/kg d.w. for the emergence ratio endpoint this value is expected for the target substance Technical Grade.

Table 1          Summary of the NOECs for Distilled and Distillation Residue Grade generated in the OECD TG218 tests and the interpolated value for Technical Grade

 

NOEC values for different substances in the OECD TG218 tests
Distilled Grade (Source substance)	Distillation Residue Grade (Source substance)	Technical Grade (Target substance)
500 mg/kg d.w. (Experimental value based on nominal loading rate data)	500 mg/kg d.w. (Experimental value based on nominal loading rate data)	500 mg/kg d.w. (Interpolated value based on nominal loading rate data)

 

Validity criteria fulfilled:

yes

Conclusions:

The effects values for the long-term toxicity to sediment dwelling organism 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 emergence ratio for organisms exposed to Technical Grade at concentrations of 62.5 to 500 mg/kg d.w. The resulting No Observed Effect Concentrations for both tests was a nominal concentration of 500 mg/kg d.w, which was interpolated to the target substance Technical Grade.

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 the 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 Grade and Distillation Residue Grade.

 

In the valid (Reliable without restriction, Klimisch Code 1) OECD TG218 Sediment-Water Toxicity Studies with Chironomus riparius on Distilled and Distillation Residue Grades groups of test organisms were exposed to blank and solvent sediment controls and the test substance at nominal concentrations of 62.5, 125, 250, 500 and 1000 mg/kg dry weight. The measured endpoints were the total number of adults emerged (emergence ratio) and the development rate. 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 Grade and Distillation Residue Grade the No Observed Effect Concentration NOEC(ER) for emergence ratio was a nominal concentration of 500 mg/kg d.w. The No Observed Effect Concentrations NOEC(DR) for development rate was a nominal concentration of 1000 mg/kg d.w. for both test substances. Since the results obtained for Distilled and Distillation Residue Grade were the same for the “Aquatic toxicity - Long-term toxicity testing on sediment organisms endpoint” (namely a NOEC of 500 mg/kg d.w.) this value has been estimated for the target substance Technical Grade.

Key value for chemical safety assessment

EC10, LC10 or NOEC for freshwater sediment:

500 mg/kg sediment dw

Additional 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 and Distillation Residue Grades.  In both OECD TG218 Sediment-Water Toxicity Studies with Chironomus riparius on Distilled and Distillation Residue Grades  the No Observed Effect Concentration NOEC(ER) for emergence ratio was a nominal concentration of 500 mg/kg d.w. The No Observed Effect Concentrations NOEC(DR) for development rate was a nominal concentration of 1000 mg/kg d.w. for both test substances. Since the results obtained for Distilled and Distillation Residue Grade were the same (NOEC of 500 mg/kg d.w.) this value has been estimated for the target substance Technical Grade.