[ethylenebis[nitrilobis(methylene)]]tetrakisphosphonic acid, calcium sodium salt

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to an appropriate OECD test guideline, with acceptable restrictions. The restrictions were that only a short exposure time was used.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Deviations:

yes

Remarks:

short exposure time (1 cell cycle)

GLP compliance:

yes

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

EDTMP-H

IUPAC Name:

EDTMP-H

Constituent 2

Reference substance name:

[ethane-1,2-diylbis[nitrilobis(methylene)]]tetrakisphosphonic acid

EC Number:

215-851-5

EC Name:

[ethane-1,2-diylbis[nitrilobis(methylene)]]tetrakisphosphonic acid

Cas Number:

1429-50-1

Molecular formula:

C6H20N2O12P4

IUPAC Name:

{ethane-1,2-diylbis[nitrilobis(methylene)]}tetrakis(phosphonic acid)

Method

Species / strain

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Details on mammalian cell type (if applicable):

- Type and identity of media: Ham's F12 with 5% newborn calf serum
- Properly maintained: yes

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat liver S9

Test concentrations with justification for top dose:

10-50 µg/ml

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: growth medium
- Justification for choice of solvent/vehicle:: none given in report

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

without metabolic activation

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

Remarks:

with metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 3, 6 and 12 hours

SPINDLE INHIBITOR (cytogenetic assays): colchicine
STAIN (for cytogenetic assays): Giesma

NUMBER OF REPLICATIONS: Two different Lots, A and B were treated. The experiment with Lot A was repeated because the positive control gave a negative result. Lot A was tested with and without sodium fluoride, Lot B with and without metabolic activation.

NUMBER OF CELLS EVALUATED: 100 per culture per Lot

VALUATION: cells were evaluated for chromatid and chromosome deletions and exchanges.

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index

OTHER EXAMINATIONS:
- Determination of polyploidy: yes

Evaluation criteria:

A result is considered positive if it is statistically higher than that of the solvent control (p/=0.05).

Statistics:

T-test used for comparison between treated and solvent control results.

Results and discussion

Test results

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Any other information on results incl. tables

Table 1 summary of in vitro cytogenicity study: Lot A

Treatment	% aberrant cells		Mitotic Index
	-NaF	+NaF	-NaF	+NaF
	Initial experiment, 3 h harvest
0*	4	3	0.06	0.05
30	0	1	0.03	0.04
40	0	1	0.06	0.04
50	0	0	0.04	0.04
	Initial experiment, 6h harvest
0*	0	1	0.08	0.06
30	0	0	0.04	0.05
40	0	0	0.06	0.04
50	0	0	0.05	0.05
	Initial experiment, 12h harvest
0*	0	2	0.07	0.10
30	1	1	0.07	0.08
40	1	3	0.05	0.04
50	1	2	0.04	0.05
Positive control	1	1	NR	NR
	repeat experiment, 12h harvest
0*	4	6	0.08	0.09
30	4	3	0.07	0.07
40	4	3	0.04	0.04
50	3	7	0.04	0.03
Positive control	31	49	NR	NR

* Solvent control with growth medium

NR: not recorded

 

Table 2 summary of in vitro cytogenicity study: Lot B

Treatment	% aberrant cells		Mitotic Index
	-MA	+MA	-MA	+MA
	3 h harvest
0*	1	0	0.11	0.06
100	1	10	0.07	0.04
200	0	4	0.07	0.06
500	1	2	0.10	0.05
	6h harvest
0*	1	6	0.05	0.05
100	1	7	0.05	0.04
200	1	4	0.03	0.05
500	0	1	0.05	0.05
	12h harvest
0*	0	6	0.9	0.07
100	0	6	0.01	0.02
200	2	7	0.01	0.01
500	1	5	0.01	0.01
Positive control	7	14	NR	NR

* Solvent control with growth medium

NR: not recorded

Applicant's summary and conclusion

Conclusions:

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

EDTMP-H has been tested according to protocol that is similar to OECD 473. No test substance induced increase in the incidence of chromosome aberrations in Chinese hamster ovary cells was observed with or without metabolic activation in either Lot A or Lot B. Appropriate solvent and positive controls were included and gave expected results. It is concluded that the test substance is negative for the induction of chromosomal aberrations under the conditions of the test.