Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 237-163-4 | CAS number: 13676-54-5
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
![](https://echa.europa.eu/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/print_toxicological-information.png)
Endpoint summary
Administrative data
Key value for chemical safety assessment
Genetic toxicity in vitro
Description of key information
An Ames test (OECD TG 471) with BMI found no mutagenic activity under the test conditions employed.
A Chromosome Aberration test (OECD TG 473) conducted in Chinese Hamster Ovary (CHO) cells indicated clastogenic activity.
Link to relevant study records
- Endpoint:
- in vitro cytogenicity / chromosome aberration study in mammalian cells
- Remarks:
- Type of genotoxicity: chromosome aberration
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 23 February 1988 - 18 April 1988
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: see 'Remark'
- Remarks:
- The study report does not cite specific official test guidelines, however the report is thorough and the test conditions are well documented. It may be determined that the methodology is broadly consistent with modern test methods and the report does include a claim that the study was conducted according to the General Principles of Good Laboratory Practice; on this basis the study is considered reliable with restrictions.
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
- GLP compliance:
- yes
- Type of assay:
- in vitro mammalian chromosome aberration test
- Species / strain / cell type:
- Chinese hamster Ovary (CHO)
- Metabolic activation:
- with and without
- Metabolic activation system:
- Liver microsomal enzyme fraction
- Test concentrations with justification for top dose:
- 2.5, 5, 10 and 20 μg/ml
- Vehicle / solvent:
- - Vehicle(s)/solvent(s) used: DMSO
- Untreated negative controls:
- yes
- Negative solvent / vehicle controls:
- yes
- Positive controls:
- yes
- Positive control substance:
- cyclophosphamide
- ethylmethanesulphonate
- Details on test system and experimental conditions:
- METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation; in suspension; as impregnation on paper disk
DURATION
- Exposure duration: 24 hours (without S-9) and 6 hours (with S-9) + 18 hours in treatment free media
SPINDLE INHIBITOR (cytogenetic assays): demecolcine (colcemid 0.1μg/mL) 2 hours before required harvest time
STAIN (for cytogenetic assays): 2% Gurrs Giemsa R66
NUMBER OF REPLICATIONS: 2 per treatment with S-9 and 2 without S-9
NUMBER OF CELLS EVALUATED: 100 consecutive well spread metaphases from each culture
DETERMINATION OF CYTOTOXICITY
- Method: count of cells % of control
COUNT OF CELLS with POLYPLOIDY: yes - Evaluation criteria:
- KUEMS Guidelines for mutagenicity Testing (1983)
- Species / strain:
- Chinese hamster Ovary (CHO)
- Metabolic activation:
- with and without
- Genotoxicity:
- positive
- Cytotoxicity / choice of top concentrations:
- cytotoxicity
- Vehicle controls validity:
- valid
- Untreated negative controls validity:
- valid
- Positive controls validity:
- valid
- Remarks on result:
- other: strain/cell type: CHO-K1 BH4cell line
- Remarks:
- Migrated from field 'Test system'.
- Conclusions:
- It was concluded that the test substance showed evidence of cytogenic and clastogenic activities in this in vitro mamalian cell system under the test conditions employed.
- Executive summary:
A test was conducted (Safe Pharm Laboratories, 1988) in vitro in Chinese Hamster Ovary cells to assess the clastogenic potential of BMI in mammalian cells. The test was conducted using a 6-hour exposure period in the presence of metabolic activation (achieved by adding induced rat liver homogenate metabolising system) and a 24-hour exposure period in the absence of metabolic activation.
Significant dose-related increases in both toxicity and the frequency of aberrations were observed under both regimes of treatment with the test material. BMI was concluded to be clastogenic to CHO cells in vitro.
- Endpoint:
- in vitro gene mutation study in bacteria
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- From 16 July to 03 August 2012
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 471 (Bacterial Reverse Mutation Assay)
- Version / remarks:
- 1997
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
- Version / remarks:
- 2008
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)
- Version / remarks:
- 1998
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- other: Official notice of MHLW, METI and MOE, Yakushokuhatsu 0331 No 7; Seikyoku No 5; Kanpokihatsu No 110331009
- Version / remarks:
- 31 March 2011
- Qualifier:
- according to guideline
- Guideline:
- other: Notice of J MOL
- Version / remarks:
- 8 February 1999
- Qualifier:
- according to guideline
- Guideline:
- other: Japanese Ministry of Health and Welfate. Evaluation and Licensing Division, Pharmaceutical and Medical Safety Bureau, Notificiation No. 1604
- Version / remarks:
- 1 November 1999
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Type of assay:
- bacterial reverse mutation assay
- Target gene:
- Salmonella typhimurium: histidine
Escherichia coli: tryptophan - Species / strain / cell type:
- S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
- Species / strain / cell type:
- E. coli WP2 uvr A pKM 101
- Metabolic activation:
- with and without
- Metabolic activation system:
- S9-mix; S9 prepared from male rats induced with phenobarbital and 5,6-benzoflavone
- Test concentrations with justification for top dose:
- Test 1: 5, 15, 50, 150, 500, 1500 and 5000 μg/plate
Test 2: 1.5, 5, 15, 50, 150 and 500 μg/plate in the absence of S9 mix; 5, 15, 50, 150, 500 and 1500 μg/plate in the presence of S9 mix - Vehicle / solvent:
- - Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: The solubility of the test substance was assessed at 50 mg/mL in water and in dimethyl sulphoxide (DMSO). It was insoluble in water, but was soluble in DMSO. - Untreated negative controls:
- no
- Negative solvent / vehicle controls:
- yes
- True negative controls:
- no
- Positive controls:
- yes
- Positive control substance:
- sodium azide
- Remarks:
- In the absence of S9 mix for strains TA100 and TA1535
- Untreated negative controls:
- no
- Negative solvent / vehicle controls:
- yes
- True negative controls:
- no
- Positive controls:
- yes
- Positive control substance:
- 9-aminoacridine
- Remarks:
- In the absence of S9 mix for strain TA1537
- Untreated negative controls:
- no
- Negative solvent / vehicle controls:
- yes
- True negative controls:
- no
- Positive controls:
- yes
- Positive control substance:
- 2-nitrofluorene
- Remarks:
- In the absence of S9 mix for strain TA98
- Untreated negative controls:
- no
- Negative solvent / vehicle controls:
- yes
- True negative controls:
- no
- Positive controls:
- yes
- Positive control substance:
- 4-nitroquinoline-N-oxide
- Remarks:
- In the absence of S9 mix for strain WP2 uvrA (pKM101)
- Untreated negative controls:
- no
- Negative solvent / vehicle controls:
- yes
- True negative controls:
- no
- Positive controls:
- yes
- Positive control substance:
- other: 2-Aminoanthracene
- Remarks:
- In the presence of S9 mix for strains TA100, TA1535 and WP2 uvrA (pKM101)
- Untreated negative controls:
- no
- Negative solvent / vehicle controls:
- yes
- True negative controls:
- no
- Positive controls:
- yes
- Positive control substance:
- benzo(a)pyrene
- Remarks:
- In the presence of S9 mix for strains TA98 and TA1537
- Details on test system and experimental conditions:
- METHOD OF APPLICATION: in agar
DURATION
First test (plate incorporation)
- Exposure duration: ca. 72 hours at 37 °C
Second test (pre-incubation method)
- Pre-incubation: 30 minutes at 37 °C
- Exposure duration: ca. 72 hours at 37 °C
NUMBER OF REPLICATIONS: 3
OTHER: After exposure period, the appearance of the background bacterial lawn was examined and revertant colonies counted using an automated colony counter. - Evaluation criteria:
- If exposure to a test substance produces a reproducible increase in revertant colony numbers of at least twice (three times in the case of strains TA1535 and TA1537) the concurrent vehicle controls, with some evidence of a positive concentration-response relationship, it is considered to exhibit mutagenic activity in this test system. No statistical analysis is performed.
If exposure to a test substance does not produce a reproducible increase in revertant colony numbers, it is considered to show no evidence of mutagenic activity in this test system. No statistical analysis is performed.
If the results obtained fail to satisfy the criteria for a clear “positive” or “negative” response, even after additional testing, the test data may be subjected to analysis to determine the statistical significance of any increases in revertant colony numbers. The statistical procedures used are those described by Mahon et al (1989) and are usually Dunnett’s test followed, if appropriate, by trend analysis. Biological importance should always be considered along with statistical significance. In general, treatment-associated increases in revertant colony numbers below two or three times the vehicle controls are not considered biologically important. It should be noted that it is acceptable to conclude an equivocal response if no clear results can be obtained.
Occasionally, these criteria may not be appropriate to the test data and, in such cases, the Study Director would use his/her scientific judgement. - Statistics:
- None stated
- Species / strain:
- S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
- Metabolic activation:
- with and without
- Genotoxicity:
- negative
- Cytotoxicity / choice of top concentrations:
- no cytotoxicity
- Remarks:
- below 500 μg/plate in the absence of S9 mix, and below 1500 μg/plate in the presence of S9 mix
- Vehicle controls validity:
- valid
- Positive controls validity:
- valid
- Species / strain:
- E. coli WP2 uvr A pKM 101
- Metabolic activation:
- with and without
- Genotoxicity:
- negative
- Cytotoxicity / choice of top concentrations:
- no cytotoxicity
- Remarks:
- below 500 μg/plate in the absence of S9 mix, and below 1500 μg/plate in the presence of S9 mix
- Vehicle controls validity:
- valid
- Positive controls validity:
- valid
- Additional information on results:
- First test
Toxicity (observed as thinning of the background lawn of non-revertant colonies, together with a reduction in revertant colony numbers) was seen in all strains following exposure to the test substance at concentrations of 500 μg/plate and above in the absence of S9 mix, and 1500 μg/plate and above in the presence of S9 mix. Precipitate was observed on all plates containing the test substance at concentrations of 500 μg/plate and above. Maximum exposure concentrations of 500 μg/plate in the absence of S9 mix and 1500 μg/plate in the presence of S9 mix were, therefore, selected for use in the second test.
No substantial increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to the test substance at any concentration tested in either the presence or absence of S9 mix.
Second test
Toxicity (observed as thinning of the background lawn of non-revertant colonies, together with a reduction in revertant colony numbers) was seen in all strains following exposure to the test substance at 500 μg/plate in the absence of S9 mix, and 1500 μg/plate in the presence of S9 mix. Precipitate was observed on all plates containing the test substance at concentrations of 500 μg/plate and above.
No substantial increases in revertant colony numbers over control counts were obtained with any of the tester strains following exposure to the test substance at any concentration tested in either the presence or absence of S9 mix. - Remarks on result:
- other: all strains/cell types tested
- Conclusions:
- It was concluded that BMI showed no evidence of mutagenic activity in this bacterial system under the test conditions employed.
- Executive summary:
BMI was assessed for the ability to cause gene mutation inSalmonella typhimurium and Escherichia coli. The study was conducted in accordance with GLP and to OECD guideline 471 (Huntingdon Life Sciences, 2012). In this main study 4 strains ofSalmonella Typhimuriumand one strain of Escherichia Coli were treated with test substance in the absence and in the presence of S9 mix. For the first test, concentrations tested were up to 5000 µg per plate. Results were negative for all strains at all concentrations therefore a second test was conducted. This employed the pre-incubation assay. Maximum concentrations were 500 µg/plate in the absence of S9 mix and 1500 µg/plate in the presence of S9 mix. Again results were negative for all strains at all concentrations. Therefore there was no evidence of mutagenic activity in this bacterial system under the test conditions employed.
Referenceopen allclose all
Cytotoxicity
Cell counts for the treatment without S-9 24 hour treatment
|
Without S-9 |
||||
Culture A |
Culture B |
Mean % |
|||
Concentration of MB-3000 (μg/mL) |
No of cells X105 |
% of control |
No of cells X105 |
% of control |
|
0 |
3.75 |
100 |
2.86 |
100 |
100 |
2.5 |
2.96 |
79 |
3.06 |
107 |
93 |
5.0 |
2.35 |
63 |
2.69 |
94 |
78.5 |
10.0 |
1.86 |
50 |
1.69 |
59 |
54.5 |
20.0 |
1.34 |
36 |
1.59 |
56 |
46.0 |
EMS 1 mg/mL |
1.84 |
49 |
1.78 |
62 |
55.5 |
Cell counts for the treatment with S-9 6 hour treatment
|
With S-9 |
||||
Culture A |
Culture B |
Mean % |
|||
Concentration of MB-3000 (μg/mL) |
No of cells X105 |
% of control |
No of cells X105 |
% of control |
|
0 |
1.80 |
100 |
1.52 |
100 |
100 |
2.5 |
1.91 |
106 |
1.45 |
95 |
100.5 |
5.0 |
1.66 |
92 |
1.61 |
106 |
99 |
10.0 |
1.23 |
68 |
1.37 |
90 |
79 |
20.0 |
1.07 |
59 |
0.68 |
45 |
52 |
CP 25 ug/mL |
1.69 |
94 |
1.63 |
107 |
100.5 |
Result of Chromosome aberration assay
Treatment without S-9
Treatment group |
Treatment time (hr) |
Con-centration |
No of diploid cells scored |
Cells with polyploidy |
No of cells with observed structural aberrations |
|||||||||||
N |
% |
Judge-ment |
GAPS |
Chromatid |
Chromosome |
Others |
Total No Cells with aberration |
Judge-ment |
||||||||
g |
ctb |
cte |
csb |
cse |
X |
Z |
-g |
+g |
||||||||
Solvent control |
24 |
0 |
100 |
10 |
(9.1) |
- |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
2 |
3 |
- |
100 |
11 |
(9.9) |
2 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
2 |
|||||
200 |
21 |
(9.5) |
3 (1.5) |
0(0) |
0(0) |
2(1) |
0(0) |
0(0) |
0(0) |
2(1) |
5(2.5) |
|||||
MB-3000 |
24 |
2.5 |
100 |
12 |
(10.7) |
- |
1 |
2 |
0 |
2 |
1 |
0 |
0 |
5 |
6 |
+ |
100 |
8 |
(7.4) |
5 |
0 |
0 |
4 |
1 |
0 |
0 |
5 |
10 |
|||||
200 |
20 |
(9.1) |
6 (3) |
2 (1) |
0(0) |
6(3) |
2(1) |
0(0) |
0(0) |
10(5) |
16 (8) |
|||||
5.0 |
100 |
17 |
(14.5) |
- |
4 |
0 |
0 |
1 |
0 |
0 |
0 |
1 |
5 |
+ |
||
100 |
6 |
(5.7) |
4 |
0 |
0 |
5 |
0 |
2 |
1 |
7 |
10 |
|||||
200 |
23 |
(10.3) |
8 (4) |
0(0) |
0(0) |
6(3) |
0(0) |
2(1) |
1(0.5) |
8(4) |
15(7.5) |
|||||
10.0 |
100 |
11 |
(9.9) |
- |
7 |
0 |
1 |
9 |
0 |
0 |
1 |
10 |
15 |
+ |
||
100 |
8 |
(7.4) |
4 |
4 |
1 |
4 |
1 |
0 |
6 |
8 |
12 |
|||||
200 |
19 |
(8.7) |
11 (5.5) |
4(2) |
2(1) |
13(6.5) |
1(0.5) |
0(0) |
7(3.5) |
18(9) |
27(13.5) |
|||||
20.0 |
100 |
9 |
(8.3) |
- |
3 |
5 |
2 |
5 |
2 |
0 |
4 |
13 |
15 |
+ |
||
100 |
9 |
(8.3) |
6 |
2 |
1 |
5 |
0 |
1 |
5 |
7 |
13 |
|||||
200 |
18 |
(8.3) |
9 (4.5) |
7(3.5) |
3(1.5) |
10(5) |
2(1) |
1(0.5) |
9(10.5) |
20 |
28(14) |
|||||
EMS |
24 |
1000 |
50 |
6 |
(10.7) |
- |
22 |
17 |
21 |
14 |
3 |
4 |
0 |
43 |
44 |
- |
50 |
3 |
(5.7) |
14 |
12 |
15 |
19 |
3 |
3 |
0 |
33 |
39 |
|||||
100 |
9 |
(8.3) |
36 (36) |
29(29) |
36 (36) |
33(33) |
6(6) |
7(7) |
0(0) |
76(76) |
83(83) |
Treatment with S-9
Treatment group |
Treatment time (hr) |
Con-centration |
No of diploid cells scored |
Cells with polyploidy |
No of cells with observed structural aberrations |
|||||||||||
N |
% |
Judge-ment |
GAPS |
Chromatid |
Chromosome |
Others |
Total No Cells with aberration |
Judge-ment |
||||||||
g |
ctb |
cte |
csb |
cse |
X |
Z |
-g |
+g |
||||||||
Solvent control |
6 |
0 |
100 |
14 |
(12.2) |
- |
6 |
1 |
1 |
3 |
0 |
0 |
0 |
5 |
11 |
- |
100 |
2 |
(2.0) |
4 |
1 |
1 |
3 |
1 |
0 |
0 |
6 |
10 |
|||||
200 |
16 |
(7.4) |
10 (5) |
2(1) |
2(1) |
6(3) |
1(0.5) |
0(0) |
0(0) |
11(5.5) |
21(10.5) |
|||||
MB-3000 |
6 |
2.5 |
100 |
10 |
(9.1) |
- |
1 |
0 |
0 |
1 |
1 |
0 |
0 |
2 |
3 |
+ |
100 |
8 |
(7.4) |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
|||||
200 |
18 |
(8.3) |
2 (1) |
0(0) |
0(0) |
1(0.5) |
1(0.5) |
0(0) |
0(0) |
2(1) |
4 (2) |
|||||
5.0 |
100 |
6 |
(5.7) |
- |
2 |
0 |
2 |
1 |
0 |
0 |
2 |
3 |
5 |
+ |
||
100 |
6 |
(5.7) |
6 |
1 |
1 |
0 |
0 |
0 |
0 |
1 |
6 |
|||||
200 |
12 |
(5.7) |
8 (4) |
1(0.5) |
3(1.5) |
1(0.5) |
0(0) |
0(0) |
2(1) |
4(2) |
11(5.5) |
|||||
10.0 |
100 |
11 |
(9.9) |
- |
7 |
6 |
3 |
2 |
0 |
0 |
4 |
11 |
16 |
+ |
||
100 |
8 |
(7.4) |
3 |
2 |
4 |
5 |
1 |
0 |
2 |
9 |
11 |
|||||
200 |
19 |
(8.7) |
10 (5) |
8(4) |
7(3.5) |
7(3.5) |
1(0.5) |
0(0) |
6(3) |
20(10) |
27(13.5) |
|||||
20.0 |
100 |
4 |
(3.8) |
- |
7 |
8 |
2 |
4 |
0 |
0 |
8 |
11 |
17 |
+ |
||
100 |
6 |
(5.7) |
6 |
3 |
7 |
4 |
2 |
0 |
9 |
15 |
19 |
|||||
200 |
10 |
(4.8) |
13 (6.5) |
11(3.5) |
9(4.5) |
8(4) |
2(1) |
0(0) |
17(8.5) |
26(13) |
36(18) |
|||||
CP |
6 |
25 |
50 |
8 |
(13.8) |
- |
9 |
9 |
14 |
29 |
2 |
0 |
0 |
38 |
40 |
- |
50 |
8 |
(13.8) |
8 |
11 |
7 |
33 |
1 |
0 |
0 |
42 |
43 |
|||||
100 |
16 |
(13.8) |
17 (17) |
20(20) |
21(21) |
62(62) |
3(3) |
0(0) |
0(0) |
80(80) |
83(83) |
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (positive)
Genetic toxicity in vivo
Description of key information
An in vivo Alkaline Comet Assay (OECD TG 489) in rats showed no indication of DNA strand breakage in the liver, glandular stomach or duodenum.
Link to relevant study records
- Endpoint:
- genetic toxicity in vivo, other
- Remarks:
- In vivo alkaline comet (single cell get electrophoresis) assay
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 04 April 2018 - 18 May 2018
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 489 (In vivo Mammalian Alkaline Comet Assay)
- Version / remarks:
- Adopted 29 July 2016
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Type of assay:
- mammalian comet assay
- Species:
- rat
- Strain:
- Wistar
- Sex:
- male
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Age at study initiation: Eight to ten weeks
- Weight at study initiation: 188.0 to 218.1 g
- Assigned to test groups randomly: yes
- Fasting period before study: No
- Housing: Up to five animals per sex in solid-floor polypropylene cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: Minimum of five days
ENVIRONMENTAL CONDITIONS
- Temperature: 19 to 25°C
- Humidity: 30 to 70%
- Air changes: Approximately 15 air changes per hour
- Photoperiod: 12 hours light / 12 hours dark
IN-LIFE DATES: From: 04 April 2018 To: 18 May 2018 - Route of administration:
- oral: gavage
- Vehicle:
- - Vehicle(s)/solvent(s) used: arachis oil
- Concentration of test material in vehicle: 50 - 200 mg/mL
- Amount of vehicle: 10 mL/kg
No analysis was carried out to determine the homogeneity, concentration or stability of the test item formulation. The test item was formulated within 2 hours of it being applied to the test system; it is assumed that the formulation was stable for this duration. This exception is considered not to affect the purpose or integrity of the study. - Details on exposure:
- PREPARATION OF DOSING SOLUTIONS:
For the purpose of this study the test item was freshly prepared as required as a suspension at the appropriate concentration in arachis oil.
No analysis was carried out to determine the homogeneity, concentration or stability of the test item formulation. The test item was formulated within 2 hours of it being applied to the test system; it is assumed that the formulation was stable for this duration. This exception is considered not to affect the purpose or integrity of the study. - Duration of treatment / exposure:
- Approximately 28 hours (two doses approximately 24 hours apart; animals were killed 4 hours after the second dose)
- Frequency of treatment:
- Two doses over a 24 hour period
- Post exposure period:
- 4 hours
- Dose / conc.:
- 0 mg/kg bw/day (actual dose received)
- Remarks:
- Vehicle control
- Dose / conc.:
- 500 mg/kg bw/day (actual dose received)
- Dose / conc.:
- 1 000 mg/kg bw/day (actual dose received)
- Dose / conc.:
- 2 000 mg/kg bw/day (actual dose received)
- Remarks:
- Maximum recommended dose
- No. of animals per sex per dose:
- 2 males and 2 females - range finding group
5 males only - 500 and 1000 mg/kg
7 males - 2000 mg/kg - Control animals:
- yes, concurrent vehicle
- Positive control(s):
- N-Nitroso-N-methylurea
- Justification for choice of positive control: Substance has been found in-house to induce strand breaks and damage to DNA under the conditions of the test
- Route of administration: Oral gavage
- Doses / concentrations: Three male rats received two administrations of 25 mg/kg (10 mL/kg of a 2.5 mg/mL solution in water) approximately 24 hours apart - Tissues and cell types examined:
- Liver, glandular stomach, duodenum
- Details of tissue and slide preparation:
- Tissue Sample Requirements
Humane euthanasia was performed on the animals at the end of the exposure period using a method that did not affect the integrity of the required tissues (carbon dioxide asphyxiation).
Samples of liver, glandular stomach, and duodenum were obtained from each animal for comet processing.
Sub-samples of the liver, glandular stomach and duodenum were taken from the vehicle control animals and the dose group animals and preserved in 10% buffered formalin for possible histopathology investigations. Assessment of cytotoxicity by histopathology may have been conducted if the results from the Comet assay, or other observations, suggest cytotoxicity may have been confounding the interpretation of the Comet assay.
The tissue samples were processed under subdued lighting and over ice to provide single cell suspensions, providing sufficient cells for scoring for the comet assay as follows:
Liver - A small piece of liver (approximately 1 cm3) was washed in liver buffer, (Hanks balanced salt solution supplemented with EDTA), before being minced and filtered to provide a single cell suspension.
Glandular Stomach – A small section of the glandular stomach was immersed in stomach buffer (Hanks balanced salt solution supplemented with EDTA and EGTA) and incubated for
approximately 15 minutes on ice. The mucosal layer of the glandular stomach was removed by gentle scraping and then a single cell suspension was obtained by scraping the remaining
tissue into a small volume of stomach buffer.
Duodenum - Approximately a 2 cm piece of Duodenum was processed. This was immersed briefly in liver buffer and then scraped gently to remove any contents, incubated in liver
buffer (approximately 10 mL), on ice for 5 to 10 minutes. A single cell suspension was obtained by gentle scraping into approximately 1 mL of fresh liver buffer.
Slide Preparation:
Adequate numbers of slides were pre-coated with 0.5% normal melting point agarose and stored at room temperature. The slides were labelled for animal number, study number and tissue type prior to use for the comet assay.
Approximately 30 μL of the cell suspension was added to 270 μL of molten 0.5% low melting point (LMP) agarose, mixed thoroughly and 50 μL of this agarose/cell suspension mix was placed onto a pre-coated slide. Two gels were placed on each slide, and 4 gels were prepared for each tissue. Two of the gels were scored for Comets (A and B replicates) and two (C and D replicates) were kept in reserve in case further scoring was required or the gels were damaged during processing. The agarose/cell suspension mix was immediately covered with a glass cover slip, transferred to a cold room at approximately 4 °C in the dark for approximately 20 minutes to allow it to solidify.
Once the LMP agarose had set, the cover slips were removed and the slides gently lowered into freshly prepared lysing solution (pH 10) and refrigerated in the dark overnight. All slides went through the subsequent processing.
Following lysis, the slides were removed from the solution, briefly rinsed with neutralization buffer and placed onto the platform of an electrophoresis bath, which was filled with chilled electrophoresis buffer (pH>13), until the slide surface was just covered. The slides were then left for 20 minutes to allow the DNA to unwind, after which they were subjected to electrophoresis at approximately 0.7 V/cm (calculated between the electrodes), 300 mA for 20 minutes. The buffer in the bath was chilled during the electrophoresis period and the temperature of the electrophoresis buffer was monitored at the start of unwinding, the start of electrophoresis and the end of electrophoresis to ensure the electrophoresis solution was maintained at low temperature (2-10°C).
At the end of the electrophoresis period, the bath was switched off, the slides gently removed and placed on to a draining surface and drop wise coated with a neutralization buffer and left for at least 5 minutes. The slides were then drained and a repeat of the addition of the neutralization buffer was performed twice. The slides were further drained and fixed in cold 100% methanol for 5 minutes and allowed to air dry.
Once dry the slides were stored prior to scoring. Two of the four processed slides were scored and the remaining slides were stored as backup slides. - Evaluation criteria:
- The slides were stained just prior to analysis for comets. To each dry slide, 75 μL of propidium iodide (20 μg/mL) was placed on top of the slide and then overlaid with a clean cover slip. After a short period to allow hydration and staining of the DNA the slide was placed onto the stage of a fluorescence microscope and scored for comets using a CCD camera attached to a PC-based image analysis program, Comet IV.
Two slides for each tissue per animal were scored with a maximum of 75 cells per slide giving an accumulative total of 150 cells per tissue per animal. Care was taken to guarantee that a cell was not scored twice. The slide score data for each tissue was processed using the Excel macro program provided in Comet IV version 4.3.1. Comparisons between the vehicle control group response and that of the test item dose groups was made. The primary endpoint was percentage DNA in the tail (percentage Tail intensity and median percentage Tail intensity).
Each slide was also assessed for the incidence of ‘hedgehog’ cells to give an indication of cell integrity. - Statistics:
- A comparison was made between the vehicle control groups and the positive control groups. The individual slide score data for the percentage tail intensity and median percentage tail intensity was compared using a Students t-test with a √1+x transformation. Comparisons between the vehicle control groups and the test item dose groups were also made when it was considered that there was a marked increase over the vehicle control value.
- Key result
- Sex:
- male
- Genotoxicity:
- negative
- Toxicity:
- yes
- Vehicle controls validity:
- valid
- Negative controls validity:
- not applicable
- Positive controls validity:
- valid
- Additional information on results:
- RESULTS OF RANGE-FINDING STUDY
- Dose range: 2000 mg/kg, 2 males and 2 females
In animals dosed with test item there were no premature deaths and no clinical signs were observed.
Bone marrow slides were prepared from the range-finding experiments for quantitative assessment.
The quantitative assessment revealed that there was very modest bone marrow toxicity observed in one male and one female at 2000mg/kg which was considered to give an indication that systematic absorption of the test item had occurred.
Based on the above data the maximum tolerated dose (MTD) of the test item, 2000 mg/kg, was selected for use in the main test, with 1000 and 500 mg/kg as the lower dose levels. There was no noticeable difference in clinical signs between the male and female animals and therefore only male animals were used for the main test.
RESULTS OF DEFINITIVE STUDY
One animal from the 1000 mg/kg dose group was killed in extremis after the initial dose but this death was considered to be due to a technical error and not test item related. No clinical signs were observed in animals dosed with the test item, other than the animal which was killed prematurely. The loss of one animal from the 1000 mg/kg dose group is considered to have no impact on the study outcome since there were sufficient animals in the MTD group (2000 mg/kg) to meet the requirements of the guideline.
There were no statistically significant increases in percentage tail intensity for any of the test item dose levels in the liver, glandular stomach or duodenum tissues which exceeded the current historical control range for a vehicle, confirming the test item did not induce DNA damage in the liver, glandular stomach or duodenum. One animal in the 2000 mg/kg dose group had very high tail intensities in the glandular stomach compared with the rest of the group but this was considered to be an exception for one animal and although it increased the overall tail intensity for the group the result was not statistically significant.
There were no marked increases in hedgehog frequency for any of the test item dose levels in either of the tissues investigated. High numbers of hedgehogs observed in the glandular stomach and duodenum are characteristic of the gastro-intestinal tract where there is a high turnover of cells. - Conclusions:
- The test item did not induce any statistically significant increases in the percentage tail intensity or median percentage tail intensity in the liver, glandular stomach or duodenum and therefore the test item was considered to be unable to induce DNA strand breakage to these tissues in vivo under the conditions of the test.
- Executive summary:
As the available in-vitro data indicated the possibility of a mutagenic effect, an in-vivo Comet assay was conducted (Envigo, 2018) according to OECD TG 489 and in accordance with GLP principles. Three groups of male rats received two doses of BMI (500, 1000 and 2000 mg/kg) approximately 24 hours apart. Following dosing the rats were humanely euthanised and tissue samples were collected from the liver, glandular stomach and duodenum. The tissue samples were processed and scored for the presence of Comets which are indicative of DNA strand breakage in the assessed tissues.
The test item did not induce any statistically significant increases in the percentage tail intensity or median percentage tail intensity values in any of the tissues investigated when compared to the concurrent vehicle control group of the liver, glandular stomach or duodenum. The test item was considered to be unable to induce DNA strand breakage to the liver, glandular stomach or duodenum in vivo, under the conditions of the test.
Reference
Summary of results
Bone marrow slides were prepared from the range-finding experiments for quantitative assessment. The slides were scored per 1000 cells and the data is presented below.
Animal Code |
Sex |
Dose level (mg/kg) |
Number of polychromatic erythrocytes (PCE) |
Number of normochromatic erythrocytes (NCE) |
PCE/NCE ratio |
1-0 |
Male |
2000 |
392 |
608 |
0.64 |
1-1 |
Male |
2000 |
534 |
466 |
1.15 |
2-0 |
Female |
2000 |
511 |
489 |
1.04 |
2-1 |
Female |
2000 |
438 |
562 |
0.78 |
Summary of Results for Percentage Tail Intensity, Median Percentage Tail Intensity and Percentage Hedgehogs for each Tissue
Liver
Dose Group |
Group Mean % Hedgehogs |
Group Mean % Tail Intensity |
Group Mean of Median % Tail Intensity per Animal |
Vehicle control (Arachis oil) |
0 |
0.29 |
0.01 |
500 mg/kg BMI |
0 |
0.24 |
0.01 |
1000 mg/kg BMI |
0 |
0.22 |
0.01 |
2000 mg/kg BMI |
0 |
0.26 |
0.01 |
Positive control (MNU) |
0.16 |
18.60 |
18.45 |
|
|
|
|
Glandular stomach
Dose Group |
Group Mean % Hedgehogs |
Group Mean % Tail Intensity |
Group Mean of Median % Tail Intensity per Animal |
Vehicle control (Arachis oil) |
2.75 |
2.13 |
0.70 |
500 mg/kg BMI |
2.33 |
1.25 |
0.27 |
1000 mg/kg BMI |
1.44 |
1.40 |
0.39 |
2000 mg/kg BMI |
2.63 |
3.21 |
2.00 |
Positive control (MNU) |
25.66 |
38.75 |
37.56 |
Duodenum
Dose Group |
Group Mean % Hedgehogs |
Group Mean % Tail Intensity |
Group Mean of Median % Tail Intensity per Animal |
Vehicle control (Arachis oil) |
10.27 |
5.19 |
3.03 |
500 mg/kg BMI |
11.36 |
6.82 |
3.54 |
1000 mg/kg BMI |
10.38 |
5.58 |
3.08 |
2000 mg/kg BMI |
8.07 |
3.75 |
1.33 |
Positive control (MNU) |
14.87 |
45.87 |
45.87 |
Comet Assay Historical Control Data
Liver |
Vehicle Control |
|
|
|
|
Positive Control |
|
|
|
|
|
% Hedgehogs |
Mean % Tail Intensity |
Median % Tail Intensity |
Upper 90% of % Tail Intensity |
Standard Deviation of % Tail Intensity |
% Hedgehogs |
Mean % Tail Intensity |
Median % Tail Intensity |
Upper 90% of % Tail Intensity |
Standard Deviation of % Tail Intensity |
Minimum |
0.00 |
0.17 |
0.00 |
0.00 |
0.55 |
0.00 |
13.65 |
13.47 |
19,73 |
4.80 |
Maximum |
1.16 |
0.95 |
0.08 |
2.90 |
5.86 |
10.24 |
46.47 |
47.10 |
56.75 |
13.31 |
Mean |
0.34 |
0.47 |
0.02 |
1.23 |
1.62 |
1.56 |
23.09 |
22.87 |
32.97 |
7.95 |
Number of Experiments |
|
|
23 |
|
|
|
|
22 |
|
|
Glandular stomach |
Vehicle Control |
|
|
|
|
Positive Control |
|
|
|
|
|
% Hedgehogs |
Mean % Tail Intensity |
Median % Tail Intensity |
Upper 90% of % Tail Intensity |
Standard Deviation of % Tail Intensity |
% Hedgehogs |
Mean % Tail Intensity |
Median % Tail Intensity |
Upper 90% of % Tail Intensity |
Standard Deviation of % Tail Intensity |
Minimum |
2.75 |
2.05 |
0.54 |
5.66 |
3.15 |
4.80 |
17.96 |
14.34 |
29.83 |
9.94 |
Maximum |
11.63 |
12.74 |
6.80 |
33.92 |
14.97 |
14.56 |
48.69 |
47.59 |
70.96 |
18.47 |
Mean |
5.87 |
5.29 |
2.59 |
13.69 |
7.14 |
9.21 |
31.59 |
29.85 |
50.63 |
14.26 |
Number of Experiments |
|
|
21 |
|
|
|
|
20 |
|
|
Duodenum |
Vehicle Control |
|
|
|
|
Positive Control |
|
|
|
|
|
% Hedgehogs |
Mean % Tail Intensity |
Median % Tail Intensity |
Upper 90% of % Tail Intensity |
Standard Deviation of % Tail Intensity |
% Hedgehogs |
Mean % Tail Intensity |
Median % Tail Intensity |
Upper 90% of % Tail Intensity |
Standard Deviation of % Tail Intensity |
Minimum |
8.34 |
5.04 |
2.64 |
12.35 |
5.56 |
12.23 |
36.17 |
34.94 |
52.63 |
13.08 |
Maximum |
15.10 |
10.06 |
8.23 |
20.32 |
7.50 |
22.10 |
48.65 |
48.39 |
67.81 |
15.46 |
Mean |
10.99 |
6.36 |
4.31 |
14.45 |
6.57 |
15.40 |
43.61 |
42.99 |
62.02 |
14.52 |
Number of Experiments |
|
|
4 |
|
|
|
|
4 |
|
|
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed (negative)
Additional information
BMI was assessed for the ability to cause gene mutation in Salmonella typhimurium and Escherichia coli. The study was conducted in accordance with GLP and to OECD guideline 471 (Huntingdon Life Sciences, 2012). In this main study 4 strains of Salmonella Typhimurium and one strain of Escherichia Coli were treated with test substance in the absence and in the presence of S9 mix. For the first test, concentrations tested were up to 5000 µg per plate. Results were negative for all strains at all concentrations therefore a second test was conducted. This employed the pre-incubation assay. Maximum concentrations were 500 µg/plate in the absence of S9 mix and 1500 µg/plate in the presence of S9 mix. Again results were negative for all strains at all concentrations. Therefore there was no evidence of mutagenic activity in this bacterial system under the test conditions employed. A further bacterial reverse mutation assay (Ames test) conducted at NOTOX (2008) further found no evidence of gene mutation in any of the Salmonella or E. Coli strains tested either in the presence or absence of metabolic activation, confirming the above conclusion.
A test was conducted (Safe Pharm Laboratories, 1988) in vitro in Chinese Hamster Ovary cells to assess the clastogenic potential of BMI in mammalian cells. The test was conducted using a 6-hour exposure period in the presence of metabolic activation (achieved by adding induced rat liver homogenate metabolising system) and a 24-hour exposure period in the absence of metabolic activation.
Significant dose-related increases in both toxicity and the frequency of aberrations were observed under both regimes of treatment with the test material. BMI was concluded to be clastogenic to CHO cells in vitro.
As the available in-vitro data indicated the possibility of a mutagenic effect, an in-vivo Comet assay was conducted (Envigo, 2018). Three groups of male rats received two doses of BMI (500, 1000 and 2000 mg/kg) approximately 24 hours apart. Following dosing the rats were humanely euthanised and tissue samples were collected from the liver, glandular stomach and duodenum. The tissue samples were processed and scored for the presence of Comets which are indicative of DNA strand breakage in the assessed tissues.
The test item did not induce any statistically significant increases in the percentage tail intensity or median percentage tail intensity values in any of the tissues investigated when compared to the concurrent vehicle control group of the liver, glandular stomach or duodenum. The test item was considered to be unable to induce DNA strand breakage to the liver, glandular stomach or duodenum in vivo, under the conditions of the test.
Overall it is concluded that although the in-vitro study in Chinese Hamster Ovaries indicated a clastogenic effect, the absence of any indication of a mutagenic effect in vivo indicates that BMI does not present any concern for a genotoxic effect in humans.
Justification for classification or non-classification
BMI was found not to have induced DNA strand breakage in an in vivo study assessing the effect in the glandular stomach, duodenum or liver of rats. On the basis of this lack of an effect BMI is considered not to meet the criteria for classification for Germ Cell Mutagenicity in accordance with Annex I section 3.5 of Regulation (EC) 1272/2008 (the CLP Regulation).
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
![ECHA](/o/diss-blank-theme/images/factsheets/A-REACH/factsheet/echa_logo.png)