Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Remarks:
peer-reviewed OECD SIDS report
Cross-reference
Reason / purpose for cross-reference:
read-across source
Remarks:
link to target
Reference
Endpoint:
in vitro gene mutation study in bacteria
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Remarks:
peer-reviewed OECD SIDS report, read-across
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The ideal structure of the registered substance is a complex which consists of iron2+ as central ions and a hemiprophyrazine ring as ligand. Therefore, the endpoint in question may be both covered with data on Fe2+ salts as well as hemiprophyrazines and structurally related substances. So the read-across can be performed on both common functional groups and common breakdown products, as the read-across substances are considered breakdown products of the target substance.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Source Chemicals, for individual read-across from an analogue in the required endpoints:
- Iron dichloride, CAS 7758-94-3
- Copper, (29H,31H-phthalocyaninato(2-)-kappaN29,kappaN30,kappaN31,kappaN32)-, ((3-(dimethylamino)propyl)amino)sulfonyl derivs., CAS 68411-04-1
- Copper phthalocyanine, CAS 147-14-8
Target Chemical:
(8,20-Dihydro-8,20-diphenyl-5,24:12,17-diimino-7,10:22,19-dinitrilodibenz(f,p)(1,2,4,9,11,12,14,19)
octaazacycloicosinato(2-)-N25,N26,N27,N28)iron, CAS 50293-39-5
All substances do not contain impurities to an extent which is expected to alter the outcome of the experimental results or read-across approach.

3. ANALOGUE APPROACH JUSTIFICATION
There are no data on the respective endpoints for all read-across substances available, but if data is available on all endpoints, a clear trend is available. So in general, read-across is justified. In detail, for the single possible structural analogues, the following is concluded:
CAS 7758-94-3: Both substances contain a Fe2+ ion, and with respect to acute oral toxicity, the substance provides the worst case scenario. So an underestimation of the actual risk here is unlikely. With regard to skin sensitization, iron does not need to be regarded, as it is an endogenous substance and no cases of sensitization were ever reported. Regarding gene mutation in bacteria, it was consistently with all the other possible analogues negative, so read-across is justified. For the irritation endpoints, it is not suitable, as based on the counterion, there are acidic iron salts available, clearly overestimating the possible hazard.
CAS 68411-04-1 / CAS 147-14-8: both source and target chemical contain structurally highly related chelating rings, i.e. a hemiprophyrazine ring or a phthalocyanine ring, they predominantly only differ in the central ion. The organic ring bearing all the chelating nitrogen atoms are identical, the only differ in the way the benzyl rings are attached, which are nevertheless identical chemical groups. With regard to acute oral toxicity, their acute oral LD50 values are way above the limit of classification, the precautionary classification of the target chemical as Acute tox. Cat. 4 does certainly not underestimate the actual risk. Regarding gene mutation in bacteria, all possible analogues are consistently negative ±S9. With regard to irritation and sensitisation, the organic functional groups are more relevant than the central ions, so read-across is also here justified.

4. DATA MATRIX
There is currently no data on the target chemical available, so an estimation using a worst case approach based on the properties of the available surrogates will be used:
Property CAS 50293-39-5 (target) CAS 7758-94-3 (source 1) CAS 68411-04-1 (source 2) CAS 147-14-8 (source 3)
LD50 (oral) Acute tox. Cat. 4 >300, <2000 mg/kg (rats) > 5000 mg/kg (rats) > 10000 mg/kg (rats)
>16000 mg/kg (rabbits)
Skin irritation Not irritating No data No data Not irritating
Eye irritation Not irritating No data No data Not irritating
Skin sensitization Not sensitizing No data No data Not sensitizing
Gene mutation in bacteria Negative ± S9 Negative ± S9 (OECD 471) Negative ± S9 (OECD 471) Negative ± S9 (various assays)
Reason / purpose for cross-reference:
read-across source
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
not specified
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay
Target gene:
his- / trp-
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Remarks:
Escherichia coil (strain WP2 uvrA)
Metabolic activation:
with and without
Metabolic activation system:
5% S9 mix
Test concentrations with justification for top dose:
33.3, 100, 300, 1,000, 3,000 and 5,000 μg/plate, based on pre-test, as stipulated by the guideline
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: not stated
Remarks:
not stated
Details on test system and experimental conditions:
Preliminary experiments to find the dose range were carried out using the pre-incubation method with 5 % S9 mix as a metabolic activation system. Employed doses were 1.6, 8, 40, 200, 1,000 and 5,000 μg/plate, both in the absence and in the presence of a metabolic activation system. 5,000 μg/plate was chosen as the maximum test concentration.
Key result
Species / strain:
S. typhimurium TA 1535
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 1537
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Conclusions:
Information was gathered from a peer-reviewed report / collection of data, hence, the information can be considered as sufficiently reliable to assess the mutagenic potential of the test item. There was no statistically significant difference in any tester strain up to the maximum test concentration of 5,000 µg/plate (p > 0.01). Precipitation was noted at doses greater than 300 μg/plate. It was concluded that iron dichloride did not exhibit mutagenic activity to any test strains under the test conditions.
Executive summary:

A bacterial reverse mutation test, according to OECD test guideline 471, was performed in compliance with GLP. In the main study, iron dichloride did not increase reverse mutations of Salmonella typhimurium (strains TA 98, TA 100, TA 1535 and TA 1537) and Escherichia coli (strain WP2 uvrA) with and without a metabolic activation system at 33.3, 100, 300, 1,000, 3,000 and 5,000 μg/plate. There was no statistically significant difference up to the maximum test concentration of 5,000 μg/plate (p > 0.01). Precipitation was noted at doses greater than 300 μg/plate. It was concluded that iron dichloride did not exhibit mutagenic activity to any test strains under the test conditions.

Data source

Reference
Reference Type:
review article or handbook
Title:
Unnamed
Year:
2004

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
not specified
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Reference substance name:
Iron dichloride
EC Number:
231-843-4
EC Name:
Iron dichloride
Cas Number:
7758-94-3
IUPAC Name:
iron(2+) dichloride
Test material form:
solid
Remarks:
commercial product: liquid
Details on test material:
Water solubility : 650 g/L at 25 °C
Molecular Weight: 126.75
Synonyms:
Iron chloride (FeCl2)
Ferrous chloride
Ferrous chloride (FeCl2)
Ferrous dichloride
Iron protochloride
Iron(2+) chloride
Iron(II) chloride
Iron(II) chloride (FeCl2)
Iron(II) chloride (1:2)
Iron dichloride is in the form of white rhombohedral crystals and sometimes it has a green tint and the substance is very hygroscopic. Iron dichloride dihydrate (FeCl2•2H2O) is in the form of white monoclinic crystals with a pale green tint and loses 1 H2O at 120 °C. Also the substance is reported to lose 1 H2O at 150 – 160 °C. Iron dichloride tetrahydrate (FeCl2•4H2O) is in the form of pale green to blue-green monoclinic crystals or cryst powder and loses 2 H2O at 105 – 115 °C

Method

Target gene:
his- / trp-
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Remarks:
Escherichia coil (strain WP2 uvrA)
Metabolic activation:
with and without
Metabolic activation system:
5% S9 mix
Test concentrations with justification for top dose:
33.3, 100, 300, 1,000, 3,000 and 5,000 μg/plate, based on pre-test, as stipulated by the guideline
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: not stated
Controls
Remarks:
not stated
Details on test system and experimental conditions:
Preliminary experiments to find the dose range were carried out using the pre-incubation method with 5 % S9 mix as a metabolic activation system. Employed doses were 1.6, 8, 40, 200, 1,000 and 5,000 μg/plate, both in the absence and in the presence of a metabolic activation system. 5,000 μg/plate was chosen as the maximum test concentration.

Results and discussion

Test resultsopen allclose all
Key result
Species / strain:
S. typhimurium TA 1535
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 1537
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Key result
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Information was gathered from a peer-reviewed report / collection of data, hence, the information can be considered as sufficiently reliable to assess the mutagenic potential of the test item. There was no statistically significant difference in any tester strain up to the maximum test concentration of 5,000 µg/plate (p > 0.01). Precipitation was noted at doses greater than 300 μg/plate. It was concluded that iron dichloride did not exhibit mutagenic activity to any test strains under the test conditions.
Executive summary:

A bacterial reverse mutation test, according to OECD test guideline 471, was performed in compliance with GLP. In the main study, iron dichloride did not increase reverse mutations of Salmonella typhimurium (strains TA 98, TA 100, TA 1535 and TA 1537) and Escherichia coli (strain WP2 uvrA) with and without a metabolic activation system at 33.3, 100, 300, 1,000, 3,000 and 5,000 μg/plate. There was no statistically significant difference up to the maximum test concentration of 5,000 μg/plate (p > 0.01). Precipitation was noted at doses greater than 300 μg/plate. It was concluded that iron dichloride did not exhibit mutagenic activity to any test strains under the test conditions.