Benzidine-2,2'-disulphonic acid

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Genetic toxicity in vitro for Benzidine-2,2’-disulphonic acid in Salmonella (Strain: TA100) was observed to be negative with metabolic activation (10% HLI ; 30% HLI; 10% RLI; 30% RLI) and without metabolic activation.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Qualifier:

according to guideline

Guideline:

other:

Principles of method if other than guideline:

Ames Test: Preincubation:
In the standard protocol (preincubation) for conducting the Ames assay, a test tube containing a suspension of one strain of Salmonella typhimurium (or E. coli) plus S9 mix or plain buffer without S9, is incubated for 20 minutes at 37º C with the test chemical. Control cultures, with all the same ingredients except the test chemical, are also incubated. In addition, positive control cultures are prepared; these contain the particular bacterial tester strain under investigation, the various culture ingredients, and a known potent mutagen*. After 20 minutes, agar is added to the cultures and the contents of the tubes are thoroughly mixed and poured onto the surface of Petri dishes containing standard bacterial culture medium. The plates are incubated, and bacterial colonies that do not require an excess of supplemental histidine appear and grow. These colonies are comprised of bacteria that have undergone reverse mutation to restore function of the histidine-manufacturing gene. The number of colonies is usually counted after 2 days.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Target gene:

Salmonella Strain: TA100

Species / strain / cell type:

S. typhimurium TA 100

Metabolic activation:

with and without

Metabolic activation system:

10% HLI,30% HLI ,10% RLI ,30% RLI

Test concentrations with justification for top dose:

0 -10000 ug/Plate

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

other: Dimethyl Sulfoxide

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

Migrated to IUCLID6: absence of S9

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

other: Dimethyl Sulfoxide

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene ( with S9)

Species / strain:

S. typhimurium TA 100

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with

Genotoxicity:

negative

Remarks:

10% HLI(induced male Syrian hamster liver S9)

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with

Genotoxicity:

not specified

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

 Strain: TA100

Dose	No Activation (Negative)		No Activation (Negative)		10% HLI (Negative)		30% HLI (Negative)		10% RLI (Negative)		30% RLI (Negative)
Protocol	Preincubation		Preincubation		Preincubation		Preincubation		Preincubation		Preincubation
ug/Plate	Mean	± SEM	Mean	± SEM	Mean	± SEM	Mean	± SEM	Mean	± SEM	Mean	± SEM
0	127	8.3	127	14.7	145	2.4	167	5	133	5.2	155	7.7
100	149	13.5	149	1.2	157	5.3	147	11.3	162	8.4	150	10.8
333	153	3.5	121	18.8	156	6.7	160	5.9	149	0.6	151	9.9
1000	125	1.2	137	15.9	151	3.5	156	4.3	136	4.7	150	4.1
3333	141	6.8	133	7.2	135	5	141	2	134	3.5	144	10.8
10000	154	2	139	7.5	132	5.5	153	8.3	131	9.9	149	6.7
Positive Control	876	24	1009	15.9	400	48.5	723	5.8	288	3.6	501	36.2

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation
negative without metabolic activation

Genetic toxicity in vitro for Benzidine-2,2’-disulphonic acid in Salmonella (Strain: TA100) was observed to be negative with metabolic activation (10% HLI ; 30% HLI; 10% RLI; 30% RLI) and without metabolic activation.

Executive summary:

Genetic toxicity in vitro for Benzidine-2,2’-disulphonic acid in Salmonella (Strain: TA100) was observed to be negative with metabolic activation (10% HLI ; 30% HLI; 10% RLI; 30% RLI) and without metabolic activation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

The available studies in the National Toxiclogical Program (NTP) database indicate that the chemical benzidine-2,2’-disulphonic acid is unlikely to exhibit genetic toxicity effect in the different strains of Salmonella (with or without metabolic activation).

The summary of the various studies is presented below

S. No	Genetic Toxicity result	Data source	Species
1	Negative	NTP database	S. typhimurium TA 100
2	Negative	NTP database	S. typhimurium TA 1535
3	Negative	NTP database	S. typhimurium TA 1538
4	Negative	NTP database	S. typhimurium TA 97
5	Negative	NTP database	S. typhimurium TA 98

Justification for selection of genetic toxicity endpoint

Data if from National Toxiclogical Program (NTP) database and hence considered to be reliable

Justification for classification or non-classification

From the available data, benzidine-2,2’-disulphonic acid is not classified as a genetic toxicant in the AMES study conducted with various Species of the Salmonella bacteria.