1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylindeno[5,6-c]pyran

Short-term toxicity to aquatic invertebrates

Description of key information

Freshwater: The 48h-EC50 for Daphnia magna according to OECD TG 202 was 0.194 mg/l.

Marine water: The LC50 for Acartia tonsa equivalent to OECD TG 202 was 0.47 mg/l.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

0.194 mg/L

Marine water invertebrates

Marine water invertebrates

Dose descriptor:

LC50

Effect concentration:

0.47 mg/L

Additional information

Two key studies were identified, one for freshwater and one for marine water. For fresh water the study by Chen et al. (2015) is considered key because it has the lowest EC50. Two supporting studies by Gooding et al and Kos Durjava et al. (2012) are summarised but not entered as study records.

Key study, fresh water: Chen et al. (2015), Daphnia magna, Bull. Environ. Contam. Toxicol. 95:73–79

A 48 hours study was conducted in accordance with OECD TG 202. Groups of forty daphnia (less than 24 hours old) were exposed for 48 hours to 0.1, 0.2, 0.35, 0.60, 1.0, 2.0, 3.5 and 6.0 mg/L concentrations of the substance dispersed in test water. Each test beaker was checked for immobilized D. magna at 24 and 48 h after the beginning of the test, and the EC50 was calculated. Results: Measured concentrations were close to nominal concentrations, ranging from 90 % to 102 %, and therefore the results are expressed in terms of nominal concentration. The 48h-EC50 was 0.194 mg/l.  

Key study marine water: Wollenberger et al. (2003), Acartia tonsa, the Science of the Total Environment 305: 53-64: The effects of the substance on the larval development rate of the marine copepod Acartia tonsa was investigated according to draft ISO/DIS 14669 (1997) equivalent to OECD TG 202. Groups of twenty adult Acartia tonsa were exposed for 48 hours to 6 different concentrations ranging between 0.046-1.5 mg/l. Living and dead test organisms were counted after 24 and 48 h. Mortality was identified by the lack of any movement after physical stimulation. The test concentrations were not measured. Results: For the substance nominal concentrations and calculated results are based on the percent purity of the technical grade chemical. The 48h-LC50 was 0.47 mg/l.

Supporting fresh water study: Kos Durjava et al., (2012; Cadaster project deliverable 2.5, Public Health Institute Maribor, Solvenia), Daphnia magna.

The acute toxicity towards Daphnia magna was investigated according to OECD guideline 202. Groups of twenty Daphnia (less than 24 hours old) were exposed for 48 hours to five concentrations of the substance dispersed in test water. The incidence of immobilisation was recorded for each test and control group at 48 hours. Results: The 48h-EC50 was found to be 0.3 mg/l (95% CL: 0.24 -0.39) based on measured concentrations.

 

This mussel study below is not a standard species to determine (acute) aquatic toxicity and other data on standard species are available, this study is therefore only summarized here.

Supporting fresh water study: Gooding et al. (2006), freshwater mussel (glochidia), Lampsilis cardium, Arch Environ Contam Toxicol, 51(4): 549–558: Toxicity tests on glochidia (larvae) and juveniles of the freshwater mussel Lampsilis cardium were performed. Replicate 24- and 48-h static tests with glochidia were conducted. For each test, glochidia were exposed to HHCB nominal concentrations (400, 800, and 1600 μg/L), a well water control, and an acetone solvent control. Each experiment was run twice with four replicates per concentration. Replicate 96-h static renewal toxicity tests were conducted with juvenile L. cardium. For each test, 5-d-old juveniles were used, and 15 juveniles were exposed to 6 nominal musk concentrations (50, 100, 200, 400, 800, and 1600 μg/L. All tests were conducted at 20°C under 16 h light: 8 h dark. Results are based on measured test concentrations. Tests were performed twice. Results: 48h-LC50 0.999 mg/L and >1.75 mg/L; 48h mortality on juveniles ranged from 0 to 24% so LC50 > 1 mg/l. 96h-EC50 based on growth rate were 0.153 and 0.563 mg/L for each test.