Ammonium 2-ethylhexyl sulphate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

publication

Title:

Mutagenicity Testing of Di(2-ethylhexyl)phthalate and Related Chemicals in Salmonella

Author:

Zeiger E., Haworth S., Mortelmans K., Speck W.

Year:

1985

Bibliographic source:

Environment Mutagenesis 7: 213-232 (1985)

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

An E. coli strain or S. typhimurium TA102 is lacking

Principles of method if other than guideline:

The test was performed according to OECD Guideline 471 using four S. typhimurium strains. A fifth strain (S. thypimurium TA 102, E. coli WP2 uvrA or WP2 uvrA (pKM101)) is lacking.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Sodium etasulfate

EC Number:

204-812-8

EC Name:

Sodium etasulfate

Cas Number:

126-92-1

Molecular formula:

C8H18O4S.Na

IUPAC Name:

sodium 2-ethylhexyl sulfate

Details on test material:

- Lot No.: A668K4
- Analyzed purity: 39.6%

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced rat liver S-9

Test concentrations with justification for top dose:

+S9/-S9: 0, 100, 333, 1000, 3333 and 10000 µg/plate

Vehicle / solvent:

- Solvent used: water

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: +S9: 2-aminoanthracene (all strains) ; -S9: sodium azide (TA1535, TA100); 4-nitro-o-phenylenediamine (TA98); 9-aminoacridine (TA1537)

Details on test system and experimental conditions:

Approximately 10^8 bacteria were mixed with 0.5 mL of either 0.1M sodium phosphate buffer (pH 7.4) or S-9 mix (containing 10% S-9 fraction), and 50 or 100 µL of the test chemical or solvent, in each of three tubes. This mixture was incubated at 37 °C for 20 min, following which 2 mL of molten top agar containing a trace amount of biotin and a growth-limiting amount of histidine (0.05 mM each) was added. The mixture was then poured onto minimal agar plates and incubated at 37 °C for 48 hr, after which time histidine-revertant colonies were counted.

Results and discussion

Test results

Key result

Species / strain:

S. typhimurium, other: TA98, TA100, TA1535, TA1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

True negative controls validity:

valid

Any other information on results incl. tables

Table 1: Results of the mutagenicity testing with Sodium 2-ethylhexyl sulfate

Dose	TA100		TA1535		TA1537		TA98
µg/Plate	-S9 Mean (SEM)	+S9 Mean (SEM)	-S9 Mean (SEM)	+S9 Mean (SEM)	-S9 Mean (SEM)	+S9 Mean (SEM)	-S9 Mean (SEM)	+S9 Mean (SEM)
0	159 (7.4)	158 (4.1)	32 (3.0)	16 (1.5)	13 (0.7)	16 (1.9)	30 (1.5)	44 (3.7)
100	182 (5.7)	145 (14.6)	27 (1.9)	13 (2.5)	11 (1.0)	18 (1.2)	21 (1.5)	43 (3.2)
333	186 (0.7)	136 (5.8)	27 (4.5)	15 (0.3)	11 (3.6)	19 (2.7)	28 (1.5)	39 (3.6)
1000	181 (4.6)	134 (4.4)	23 (2.8)	14 (6.0)	9 (2.5)	18 (2.0)	35 (1.9)	43 (3.8)
3333	173 (7.0)	137 (3.4)	23 (3.2)	14 (1.5)	11 (2.2)	18 (3.3)	23 (3.6)	34 (2.2)
10000	113 s (6.7)	116 (10.8)	19 (0.9)	15 (1.5)	13 (0.7)	9 (2.5)	22 (2.7)	37 (3.2)
Positive control	471 (17.5)	1262 (54.6)	359 (12.5)	438 (30.3)	215 (8.4)	491 (60.8)	815 (4.9)	1031 (178.1)

s: sligth clearing of background lawn

Applicant's summary and conclusion

Conclusions:

Under the experimental conditions reported, the test item is considered non-mutagenic in this bacterial reverse mutation assay.

Executive summary:

The substance, sodium 2-ethylhexyl sulfate, was evaluated for mutagenicity in a Bacterial Reverse Mutation Test equivalent to OECD guideline 471. Salmonella typhimurium strains TA98, TA100, TA1535 and TA 1537 were exposed to the test item at concentrations of 0, 100, 333, 1000, 3333 and 10000 µg/plate with and without metabolic activation. Under the experimental conditions of this Bacterial Reverse Mutation Test, the test item is considered non-mutagenic in this bacterial reverse mutation assay.