3,5,5-trimethylcyclohex-2-enone

Endpoint summary

Additional information

Short-term toxicity to fish

The substance is with high probability acutely not harmful to fish. (96 -h LC50 = 145mg/L, measured, Cairs and Nebeker, 1982).

 

Short-term toxicity to aquatic invertebrates

The substance with high probability acutely not harmful to aquatic invertebrates (48 -h EC50 = 120 mg/L, Le Blanc, 1980).

 

Long-term toxicity to aquatic invertebrates

A geometric mean of the lower and upper chronic endpoints, as determined in early-life-stage tests, was 14 mg/L (based on measured test concentrations, Cairns and Nebeker, 1982).

 

Toxicity to aquatic algae

The substance is with high probability acutely not harmful to algae (72 -h ErC50 = 205.2 mg/L, NITE, 2020).

 

Toxicity to microorganisms

Depending on local conditions and existing concentrations, disturbances in the biodegradation process of activated sludge are possible.

(3 h EC50 = 100 mg/L, Yoshioka and al.,1986).

 

Endocrine disrupter testing in aquatic invertebrates:

Experimental data on the endocrine toxicity of CAS 78-59-1 to aquatic organisms are published in EPA Memorandum (2015). One short-term test with fish as a test organism (2012) was performed according to the OECD Guideline 229. The test concentrations were 0 control, 0.8, 8 and 80 mg/L Adult survival in both sexes at all treatment levels was 100%; since no mortality was observed. Male and female body weight were both significantly (p<0.05) reduced 24% of control at the 79.8 mg/L treatment level. Female VTG was significantly (p<0.05) reduced 44 and 77% of control at the 7.62 and 79.8 mg/L treatment levels, respectively. Fecundity was significantly (p<0.05) reduced 94% at the 79.8 mg/L treatment. There was a significant reduction in fertility (p<0.05) at the 79.8 mg/L treatment level, which was reduced 70% compared to the control. There were no other significant effects on endpoints. Although not analyzed statistically, there were no treatment-related histopathological observations in males, but there was there was an increase in incidence of mild to moderate oocyte atresia at the 79.8 mg/L treatment level compared to the control in female fish, as well as a slight decrease in gonadal stage.

The second study was performed with a frog as a test organism (2011). The test was conducted according to OECD Guideline 231. The test lasted 21 days and the test concentrations were: control, 0.6, 6 and 60 mg/LThere were no significant effects on Day 7 or Day 21 developmental endpoints (i.e., developmental stage, normalized HLL). Similarly, no Day 7 growth endpoints were significantly affected by isophorone. However, both Day 21 wet weight (15% reduction, Jonckheere’s,p= 0.016) and Day 21 SVL (5% reduction, Jonckheere’s,p= 0.013) were significantly reduced at the mean-measured 59.0 mg /L treatment group, relative to the negative control. There were no treatment-related thyroid or other histopathological effects.

The analytical measurements of the test item concentrations were performed in both studies. The mean recovery of the test substance in a study with a fish ranged between 1.2 and 3.4%. In the study with a frog the mean recovery of isophorone was in the range between 0.767 and 6.34%. The results of both studies are based on the mean-measured test concentrations.