Bis(2-hydroxyethyl) sulphone

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was conducted between 2 September 1997 and 16 September 1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: "Standards for Mutagenicity Test using Microorganisms" of "Occupational Safety and Health Law"

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Bis(2-hydroxyethyl) sulphone

EC Number:

219-948-3

EC Name:

Bis(2-hydroxyethyl) sulphone

Cas Number:

2580-77-0

Molecular formula:

C4H10O4S

IUPAC Name:

2-(2-hydroxyethanesulfonyl)ethan-1-ol

Test material form:

solid

Specific details on test material used for the study:

Test substance: BS-1
Sample nurnber: 97-180
Concentration: 65 percent aqueous solution

Method

Target gene:

histidine

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 100

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 98

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Test concentrations with justification for top dose:

The highest dose of the test solution was 10μl because the concentration of test substance was 65%.
Solutions of five different concentration, 0. 391, 0. 156, 0. 6 25, 2. 50 and 10. 0 μl per per plate were used for dose range finding test.
For main test, concentration of the test solution was prepared to be 0. 6 25, 1.25, 2.50, 5.00 and 10.0 μl per plate.

Vehicle / solvent:

sterilized pure water

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

sterilized pure water

True negative controls:

no

Positive controls:

yes

Remarks:

dissolved in DMSO. 0.01 and 0.1µg/plate for TA100 and TA98

Positive control substance:

other: 2- ( 2-Furyl)-3- (5-nitro- 2-furyl)acrylamide (AF2)

Remarks:

without S9 mix

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

sterilized pure water

True negative controls:

no

Positive controls:

yes

Remarks:

dissolved in DMSO. 5 µg/plate for TA100 and TA98

Positive control substance:

other: Benzo[a]pyrene (BP)

Remarks:

with S9 mix

Details on test system and experimental conditions:

Control test
For the solvent control test, three plates were used.
Meanwhile, two plates were used for positive control test.
Every positive control was dissolved in DMSO and stored in a freezer at - 20 °C.

For the test substance two plates of each dose were used in every test.

Test method
Test solution (0.1 ml) was mixed with 0.1 M sodium phosphate buffer (pH 7.4, 0.5 ml) and the overnight culture of tester strain (0.1 ml) and then the mixture was pre-incubated at
37 °C for 20 minutes with gentle shaking. For metabolic activation, S9 Mix (0.5 ml) was mixed instead of 0.1 M sodium phosphate buffer. After pre-incubation, melted soft agar ( 2 ml)
was added and the resulting mixture was poured onto minimal glucose agar plate. The soft agar contained 0.5 mM D-biotin and 0.5 mM L-histidine.
After incubation for 2 days, revertant colonies were counted and average number of colonies in each dose and control were obtained.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

Dose range finding test:
The number of revertant colonies did not increase twice or more over that in negative control in test strains both with and without S9Mix.

Main test:
The number of revertant colonies did not increase twice or more over that in negative control in test strains both with and without S9Mix.

Any other information on results incl. tables

Results from the main test are presented in the table below

Test period		97/9/11~97/9/16
With (+) or without (-) S9 mix	Dose µg/plate	Number of revertant colonies /plate
		Base-pair substitution type		Frameshift type
		TA100		TA98
S9 Mix (-)	Solvent control	127		18
		167		28
		140	(145)	23	(23)
	1      0.625	136		25
		145	(141)	14	(20)
	2        1.25	155		19
		127	(141)	23	(21)
	3          2.5	140		18
		140	(140)	26	(22)
	4              5	144		14
		128	(136)	23	(19)
	5           10	137		21
		142	(140)	23	(22)
S9 Mix (+)	Solvent control	139		38
		116		48
		127	(127)	40	(42)
	1      0.625	112		39
		161	(137)	43	(41)
	2        1.25	122		40
		145	(134)	40	(40)
	3          2.5	155		37
		130	(143)	40	(39)
	4              5	136		28
		148	(142)	44	(36)
	5           10	133		27
		155	(144)	40	(34)
Positive control without S9 mix	Chemical	AF2		AF2
	Dose µg/plate	0.01		0.1
	Revertants /plate	1166 1240	(1203)	164 140	(152)
Positive control with S9 mix	Chemical	BP		BP
	Dose µg/plate	5		5
	Revertants /plate	1122 1036	(1079)	293 367	(330)

The figures in parentheses show the mean of each plate.

Positive controls

AF2: 2-(2-Furyl)-3-(5-nitro-2-furyl)acrylamide

BP: Benzo[a]pyrene

Applicant's summary and conclusion

Conclusions:

The number of revertant colonies of BS-1 did not show any tendency to increase twice or more over that in negative control
for all strains. It was confirmed that the test was appropriately performed because the negative control and the
positive control induced the reasonable increase in the number of revertant colonies.
Based on the above results, it is concluded that BS-1 was non-mutagenic in this test system.

Executive summary:

BS-1 was tested for mutagenicity using Salmonella typhimurium (TA100 and TA98) as indicator strains and the liver microsome fraction of rats for metabolic activation system (S9 Mix).

The test was carried out according to "Standards for Mutagenicity Test using Microorganisms" of "Occupational Safety and Health Law" and "GLP Standards Applied to Industrial Chemicals" of "Law Concerning the Examination and Regulation of Manufacture, etc. , of Chemical Substance".

The test substance was judged non-mutagenic in this test system.