1-Ethyl-3-methylimidazolium ethylsulfate

Endpoint summary

Description of key information

 From the results reported and based on the EC criteria for classification and labelling requirements for dangerous substances and preparations (Council Directive 67/548/EEC), a definitive No Observed Adverse Effect Level (NOAEL) for 1-ETHYL-3-METHYL IMIDAZOLIUM ETHYLSUL.FATE  of 1000 mg/kg/day was established.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEL

1 000

Study duration:

subacute

Species:

rat

Additional information

SUMMARY: Repeated dose 28-Day oral toxicity study with 1-ETHYL-3-METHYL IMIDAZOLIUM ETHYLSULFATE by daily gavage in the rat.

Based on the results of a 5 -day range finding study, the dose levels for the 28-day toxicity study were selected to be 0, 50, 150 and 1000 mg/kg/day. The study was based on the following guidelines: EC Directive 96/54/EEC, B.7 Repeated Dose (28 days) Toxicity (oral), 1996. OECD 407, Repeated Dose 28-day Oral Toxicity Study in Rodents, 1995 OPPTS 870.3050, Repeated dose 28-day oral toxicity study in rodents. Office of Prevention, Pesticides and Toxic Substances (7101), EPA 712-C-00-366, 2000. The test substance was administered daily for 28 days by oral gavage to SPF-bred Wistar rats. One control group and three treated groups were tested, each consisting of 5 males and 5 females. The following parameters were evaluated: clinical signs daily; functional observation tests; body weight and food consumption weekly; clinical pathology and macroscopy at termination; organ weights and histopathology on a selection of tissues.

RESULTS: Accuracy and homogeneity of formulations of test substance in water (Milli-U) were demonstrated by analyses. Findings that distinguished treated from control animals included: 50 mg/kg/day: None. 150 mg/kg/day: None. 1000 mg/kg/day: Clinical biochemistry deviations: Increased alanine aminotransferase activity and cholesterol levels (males); Increased potassium levels (males/females); Increased albumin levels (females).

CONCLUSION: Changes in clinical biochemistry parameters at 1000 mg/kg/day occurred in the absence of morphological evidence of organ dysfunction. Therefore, although a relation to treatment with the test substance was considered likely, these changes were considered not to be adverse in toxicological terms. From the results presented in this report and based on the EC criteria for classification and labelling requirements for dangerous substances and preparations (Council Directive 67/548/EEC), a definitive No Observed Adverse Effect Level (NOAEL) for 1-ETHYL-3-METHYL IMIDAZOLIUM ETHYLSUL.FATE of 1000 mg/kg/day was established.