Reaction mass of 2,2,6-trimethyl-1-oxaspiro[2.5]oct-5-ene and 4-isopropylidene-1-methylcyclohexene

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Justification for type of information:

TERPINOLENE MONOCONSTITUENT (source substance) is one of the main constituents of the registered substance (target substance).

Reason / purpose for cross-reference:

read-across source

Details on sampling:

Sampling method: samples were taken at the start (t = 0 h) and every 24 h thereafter in old and new solutions and the control.

Storage: samples were analysed directly after sampling.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.634 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95%CL: 0.332-0.823

Details on results:

no details

Results with reference substance (positive control):

Results with reference substance are valid.

EC50: 0.97 mg/L

Reported statistics and error estimates:

The software ToxRat® Professional was used for the determination of the effective concentrations. The EC50 value was determined by Probit analysis using linear max. likelihood regression.

Validity criteria fulfilled:

yes

Conclusions:

Under the test conditions, the 48h-EC50 of terpinolene monoconstituent on Daphnia magna was 0.634 mg/L, based on mean measured concentrations.

Based on the results of this study, terpinolene monoconstituent is classified:
- dangerous for the environment according to Directive 67/548/EEC "R50/53: very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment"
- and hazardous to the aquatic environment under Regulation (EC) No 1272/2008 (CLP) - Category Acute 1 and Category Chronic 1.

Executive summary:

An acute aquatic toxicity study was performed on Daphnia magna in accordance with GLP and OECD Guideline No 202. Following a preliminary range-finding test, twenty daphnids (four replicates, five daphnids per replicate) were exposed to an aqueous solution of terpinolene monoconstituent at the required nominal test concentrations of 0.2, 0.3, 0.4, 0.5, 0.7 and 1.0 mg/L. Immobilisation of daphnids was determined in a semi-static 48-h test by visual observation after 24 and 48 h.

The concentrations of the test item were measured at the start (t = 0 h), at t = 24 h (new and old solutions) and at the end of the test (t = 48 h). Concentrations measured in freshly prepared solutions and in 24-h old solutions revealed that the concentrations of the test item were not satisfactorily maintained within ± 20 % of the initial concentrations. Thus, the evaluation of the effects on Daphnia magna was based on the geometric mean of the measured concentrations: 0.14, 0.24, 0.33, 0.41, 0.57 and 0.82 mg/L.

The lowest observed effect concentration based on immobilisation was 0.332 mg/L. At 0.823 mg/L, 100% of daphnids were immobilised. No sublethal effects were reported.

Therefore, the 48h-EC₅₀ of terpinolene monoconstituent for Daphnia magna was estimated to be 0.634 mg/L, based on mean measured concentrations.

Based on the results of this study, terpinolene monoconstituent is classified:

- dangerous for the environment according to Directive 67/548/EEC "R50/53: very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment"

- and hazardous to the aquatic environment under Regulation (EC) No 1272/2008 (CLP) - Category Acute 1 and Category Chronic 1.

Description of key information

Data were available from scientific litterature about the sensitisation of TERPINOLENE MONOCONSTITUENT, on of the main constituents of the registered substance.

An acute aquatic toxicity study was performed on Daphnia magna in accordance with OECD Guideline No 202.
The 48h-EC50 of terpinolene monoconstituent for freshwater invertebrates is 0.634 mg/L.
Based on the results of this study, terpinolene monoconstituent is classified:
- dangerous for the environment according to Directive 67/548/EEC "R50/53: very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment"
- and hazardous to the aquatic environment under Regulation (EC) No 1272/2008 (CLP) - Category Acute 1 and Category Chronic 1.

Therefore, REACTION MASS OF 2,2,6-TRIMETHYL-1-OXASPIRO[2.5]OCT-5-ENE AND 4-ISOPROPYLIDENE-1-METHYLCYCLOHEXENE is classified:
- dangerous for the environment according to Directive 67/548/EEC "R50/53: very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment"
- and hazardous to the aquatic environment under Regulation (EC) No 1272/2008 (CLP) - Category Acute 1 and Category Chronic 1.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.634 mg/L

Additional information

Data were available from scientific litterature about the sensitisation of TERPINOLENE MONOCONSTITUENT, on of the main constituents of the registered substance.

Key study conducted according to OECD 202 Guideline and EU Method C.2 under GLP without deviation.

Daphnids were exposed to terpinolene monoconstituent at nominal concentrations of 0.2, 0.3, 0.4, 0.5, 0.7 and 1.0 mg/L. Immobilisation of daphnids was recorded in a semi-static 48-hour test by visual observation after 24 and 48 hours. Concentrations were measured at the start of the study, at 24 h (new and old solutions) and at the end of the test. The concentrations of the test item were not satisfactorily maintained within ± 20% of the initial concentrations throughout the test, thus the EC₅₀ were based on the geometric mean of the measured concentrations.

The 48h-EC₅₀ determined in this study can be used as key value for chemical safety assessment.