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Administrative data

Key value for chemical safety assessment

Additional information

Two bacterial mutation tests and two chromosomal aberration tests showed negative results.

The in vivo micronucleus test showed that monosodium glutamate has no clastogenic activity in bone marrow cells of mice (negative).

Monosodium glutamate administration at levels up to 5.0% in the diet was not carcinogenic for male and female Fischer 344 rats in the carcinogenicity study.

Based on the results of the in vivo micronucleus test and the carcinogenicity study, the mouse lymphoma study does not appear scientifically necessary.

Short description of key information:

Monosodium glutamate has been tested in two bacterial reverse mutation tests (equivalent to OECD 471 and GLP), two chromosomal aberration tests (equivalent to OECD 473 and GLP), in vivo micronucleus test (equivalent to OECD 474 and GLP) and carcinogenicity data.

Bacterial reverse mutation tests, OECD 471 (according to GLP principles):

E. coli, S. typhimurium TA 1535, TA 1537, TA 98 and TA 100 were tested with and without metabolic activation up to 5000 µg/plate. It was concluded

that the test substance is not mutagenic under the current test conditions.

Chromosomal aberration tests, OECD 473 (according to GLP principles):

Cultured Chinese Hamster Lung cells were tested with and without metabolic activation up to 1.9 mg/ml. It was concluded that the test substance is not clastogenic under the current test conditions.

In vivo micronucleus test, OECD 474 (according to GLP principles):

Monosodium L-glutamate monohydrate was administered (gavage) to male ICR mouse. The dose range was as follow: 500, 1000 and 2000 mg/kg bw/day - 5 animals per group. No treatment related effect was observed. It was concluded that the test substance is not clastogenic under the current test conditions.

Carcinogenicity, study performed in agreement with OECD 451.

Monosodium L-glutamate was administered (gavage) to female and male Fischer 344 rats. The dose range was 0.6, 1.25, 2.5 and 5.0%  (this dose level was equivalent to 1982 mg/kg bw/day for males and 2311 mg/kg bw/day for females) for 104 weeks - 50 animals per group. Effects observed were

increased urinary volume (males, 5% w/w), increased pH and sodium levels and reduced urinary potassium levels (males and females, 2.5% w/w and

5% w/w) , increased relative kidney weight (males and females, 5% w/w) and increased urinary bladder weight (males, 5% w/w). Due to the limited

number of parameters measured it is not appropriate to derive a NOAEL for toxicity from the results of this study.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

It can be concluded that monosodium glutamate is not considered mutagenic/clastogenic according to DSD and CLP.