D-gluconic acid

Endpoint summary

Additional information

In the GLP-compliant, key bacterial reverse mutation assay (conducted according to OECD guideline 471), gluconic acid (GA) solution at 50% solids was tested at doses of 0, 50, 150, 500, 1,500 or 5,000 µg/plate in  Salmonella typhimurium  strains TA 98, TA 100, TA 1535, TA 1537, and TA 102 both in the absence and presence of an exogenous metabolic activation system (Aroclor 1254-induced rat liver S9) (Sophie SIMAR, 2015a). The experiment was conducted in triplicate and an independent repeat experiment was performed (plate incorporated method and preincubation). Water was used as the vehicle and positive controls were included in all incubations. No cytotoxicity was observed at any GA concentration and no increases in the reverse mutations were noted in any strain either in the absence or presence of S9. Incubation with positive control substances in the absence or presence of S9 resulted in anticipated increases in reverse mutation rates.

In a key, GLP-compliant mammalian chromosome aberration test (according to OECD guideline 473), gluconic acid (GA) solution at 50% solids was tested at concentrations of 0, 1.25, 2.5, 5, and 10 mM in human peripheral blood lymphocytes in the absence or presence of an exogenous metabolic activation system (Aroclor 1254-induced rat liver S9) (Sophie SIMAR, 2015b). Incubations at each concentration were done in duplicate; however, an independent repeat experiment was not performed. Water was used as the vehicle control and mitomycin C and cyclophosphamide were used as the positive control compounds in the absence and presence of metabolic activation, respectively. In the 20-hour treatment without metabolic activation, a strong cytotoxicity (mitotic index of 21%) was noted at 10 mM. For other treatments, no or slight cytotoxicity was observed and no chromosome damage was noted at any GA concentration either in the absence or presence of metabolic activation. Incubations with the positive control compound resulted in anticipated increases in chromatid damage.

In a key, GLP-compliant mammalian gene mutation assay (according to OECD guideline 490), gluconic acid (GA) solution at 50% solids was tested at doses of 0, 1.25, 2.5, 5, and 10 mM in the absence or presence of an exogenous metabolic activation system (Aroclor 1254-induced rat liver S9) in L5178Y mouse lymphoma cells (Sophie SIMAR, 2015).  The experiment was conducted in duplicate and an independent repeat experiment was performed. Water was used as the vehicle and methyl methanesulfonate and cyclophosphamide were used as the positive control compounds in the absence and presence of S9, respectively. As 1 out of the 2 cultures used in the main assay with S9 presented an unacceptable level of mutation frequency, a second assay was performed under the same experimental condition. No or slight cytotoxicity was observed and biologically significant increases in the mutant frequency were not noted at any GA concentration either in the absence or presence of S9. Incubation with positive control substances in the absence or presence of S9 resulted in anticipated increases in the mutation frequencies.

Short description of key information:
The genetic toxicity potential of gluconic acid (GA) has been assessed in 3 in vitro studies (including a bacterial reverse mutation assay, an in vitro mammalian chromosome aberration assay, and an in vitro mammalian cell gene mutation test). Negative results were reported in all studies.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

The substance does not meet the criteria for classification and labelling for this endpoint, as set out in Regulation (EC) NO. 1272/2008.