2-chloroethanol

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study is comparable to OECD Guideline 471 with acceptable restrictions (no 2nd trial for verification of weak positive effects at dose levels between 2 and 5 mg/plate).

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Mutagenicity Test Data of Existing Chemical Substances

Author:

JETOC

Year:

1996

Bibliographic source:

Edited and Published January 1996 by Japan Chemical Industry Ecology-Toxicology & Information Center, Japan

Reference 2

Reference Type:

publication

Title:

Mutagenicity Test Data of Existing Chemical Substances

Author:

JETOC

Year:

1997

Bibliographic source:

Edited and Published February 1997 by Japan Chemical Industry Ecology-Toxicology & Information Center, Japan

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-chloroethanol

EC Number:

203-459-7

EC Name:

2-chloroethanol

Cas Number:

107-07-3

Molecular formula:

C2H5ClO

IUPAC Name:

2-chloroethan-1-ol

Details on test material:

JETOC 1996
Purity: 99.2%, source: Wako Pure Chem. Japan, no further data
JETOC 1997
Purity 98.0%, source: Aldrich Chemicals Inc.; Lot no.: 16520P X; no further data

Method

Target gene:

His- in Salmonella typhimurium
Trp- in E. coli

Species / strain

Species / strain / cell type:

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

Details on mammalian cell type (if applicable):

plus E. coli WP2uvrA

Metabolic activation:

with and without

Metabolic activation system:

Sodium phenobarbital i.p. injected into male Sprague-Dawley rats (200 g) at a dosage of 30 mg/kg bw/day for 4 days before sacrifice; liver S9 prepared and mixed with supplements.

Test concentrations with justification for top dose:

JETOC 1996: 0, 50, 100, 200, 500, 1000, 2000, 5000 µg/plate.
JETOC 1997: 0, 0.08, 0.3, 1.2, 4.9, 19.5, 78, 313, 1250, 5000 µg/plate.
5 mg/plate is the max. recommended concentration according to OECD 471.

Vehicle / solvent:

DMSO in both experiments

Controls

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: see below

Details on test system and experimental conditions:

JETOC tested 2-chloroethanol 1996 and 1997 under similar experimental conditions but different sources for the test substance. Both results are presented in this data sheet.
The authors used the preincubation method (Matsushima et al., 1980). All plates were incubated for 48 hours at 37°C and the numbers of revertant colonies were scored.

Determination of cytotoxicity
Growth of the background lawn of tester strains on each plate examined under a stereo microscope. The decrease in back-ground lawn is a measure for bactericidal effects (decrease in the number of micro colonies and an increase in their diameter).

Positive control
AF2: 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide, used without S9-mix in TA98 (0.1 µg/plate), WP2uvrA (0.01 µg/plate) and in TA100 (0.01 µg/plate)
NaN3: sodium azide, used withot S9-mix in TA1535 (0.5 µg/plate)
9AA : 9-aminoacridine, used without S9-mix in TA1537 (80 µg/plate)
2AA : 2-amino anthracene, used with S9-mix in all strains at concentrations between 0.5 µg/plate (TA98) and 10 µg/plate (WP2uvrA).

Evaluation criteria:

Positive:
1) dose-dependent effects
2) at least 2-fold increase in revertants

Statistics:

no data

Results and discussion

Test results

Test results 1

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 nor precipitates, but tested up to recommended limit concentrations

Remarks:

(tested up to 5 mg/plate)

Vehicle controls validity:

other: some values not within the historical vehicle controls (see Table below)

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

without

Genotoxicity:

positive

Remarks:

but only at 5 mg/plate; negative results with S9-mix

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

other: slightly higher than historical vehicle control (see Table below)

Positive controls validity:

valid

Test results 3

Species / strain:

other: TA1537, TA98, TA100, WP2uvrA

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(at 5 mg/plate without S9-mix; tested up to limit concentrations)

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with

Genotoxicity:

positive

Remarks:

but only at 5 mg/plate; negative results without S9-mix

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

A summary Table of results is presented below.

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: no data
- Effects of osmolality: no data
- Precipitation: no data, but no precipitation expected

COMPARISON WITH HISTORICAL CONTROL DATA:
on page 33 (Table 2) historical control data were given; these data were also presented in the Table below


ADDITIONAL INFORMATION ON CYTOTOXICITY: see Table below

Remarks on result:

other: other: 1st test in JETOC1996

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Ames test in JETOC 1996

Revertants per plate, mean of of two plates given, cytotoxicity marked by *

Dose in µg per plate	TA100		TA1535		WP2uvrA		TA98		TA1537
	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9
Historical vehicle	138+-27	139+-29	14+-5	13+-4	29+-11	34+-11	20+-8	26+-7	8+-2	11+-4
Current vehicle	142	152	22	17	43	47	17	25	4	7
50	156	162	21	16	44	55	13	32	6	6
100	148	164	17	14	33	38	16	25	8	5
200	151	166	11	14	45	52	21	30	6	8
500	148	172	18	11	40	50	17	42	4	4
1000	138	168	20	15	39	58	11	33	6	4
2000	158	143	20	15	65	64	21	38	6	5
5000	198	171	29	25	186	79	24	33	7	7
Positive control	635	1455	315	510	553	1022	448	479	600	354

x

x

Ames test in JETOC 1997

Revertants per plate, mean of of two plates given, cytotoxicity marked by *

Dose in µg per plate	TA100		TA1535		WP2uvrA		TA98		TA1537
	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9
Historical vehicle	138+-27	139+-29	14+-5	13+-4	29+-11	34+-11	20+-8	26+-7	8+-2	11+-4
Current vehicle	149	163	15	16	32	39	19	27	11	13
0.08	168	166	19	17	33	44	21	25	7	13
0.3	161	157	19	14	34	38	21	25	12	17
1.2	149	148	15	19	32	36	20	18	10	14
4.9	175	169	12	15	28	35	12	28	9	12
19.5	164	175	17	15	28	39	13	26	6	15
78	160	171	16	16	26	44	19	25	9	16
313	183	168	12	13	31	39	22	23	14	14
1250	165	185	14	24	38	43	19	16	9	14
5000	203*	167	20*	37	52	65	25*	20	11*	10
Positive control	765	920	362	242	177	917	510	203	471	177

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
other: weak positive

Weak positive results only at a dose level of 5 mg/plate (limit concentration) which are not reproducible in independent experiments.

Executive summary:

The study is comparable to OECD Guideline 471 with accepatable restrictions (no 2nd trial for verification of weak positive effects at dose levels between 2 and 5 mg/plate).

In the Ames test on S. typhimurium TA1535, TA1537, TA98, TA100, and E. coli WP2uvrA the bacteria were exposed with and without metabolic activation in a first test (JETOC 1996) to 0, 50, 100, 200, 500, 1000, 2000, 5000 µg/plate and in a 2nd test (JETOC 1997) to 0, 0.08, 0.3, 1.2, 4.9, 19.5, 78, 313, 1250, 5000 µg/plate. In the first test an increase in the number of revertants was detected only in WP2uvrA without S9 -mix at the highest dose level of 5 mg/plate which is the limit concentration according to OECD 471. Negative results in WP2uvrA were obtained in a 2nd test (JETOC 1997) at the limit dose level of 5 mg/plate. In the 2nd test weak positive results were found only in TA1535 with S9 -mix, again at the high dose level of 5 mg/plate. Negative results were seen in the 1st test in this strain at the same concentration.

Conclusion: Weak positive results only at a dose level of 5 mg/plate (limit concentration) which are not reproducible in independent tests.