Ethylamine

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Based on an Ames-Test (Mortelmans, 1986), which meets generally accepted scientific principles and which is acceptable for assessment, the test substance is not mutagenic in the Salmonella/microsome preincubation assay with and without metabolic activation.

Link to relevant study records

Reference

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:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

only 4 strains were tested

Qualifier:

no guideline followed

Principles of method if other than guideline:

The test substance was assayed for mutagenicity in the Salmonella/microsome preincubation assay using a standard protocol approved by the National Toxicology Program [see also Haworth et al, 1983].
To the 13 X 100-mm test tube maintained at 37°C the following substances were added:
0.5 ml of S-9 mix or 0.1 M PO4 buffer (pH 7.4), 0.05 ml of the overnight culture, and 0.05 ml of solvent or chemical dilution.

The mixture was mixed and allowed to incubate without shaking at 37°C for 20 min, at which time 2.0 ml of molten (45°C) top agar supplemented with 0.5 mM L-histidine and 0.5 mM D-biotin were added. The contents of the tubes were mixed and poured onto 25 ml of minimal glucose bottom agar [Vogel and Bonner, 1956] in 15 X 100-mm plastic petri dishes (Falcon Muta-Assay, 1028). When the top agar had solidified, the plates were inverted and incubated at 37°C for 48 hr. Concurrent solvent and positive controls were tested with and without the metabolic activation systems. Five dose levels of the test substance was tested, with three plates per dose level in four strains.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

- Supplier: Fluka Chemical Co.
- Testing lab: SRI

Target gene:

Histidine

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Type and composition of metabolic activation system:
- source of S9: Male Sprague-Dawley rats and male syrian hamsters; liver S9
- method of preparation of S9 mix: Aroclor 1254 (200 mg/ml in corn oil) was administered ip at 500 mg/kg 5 days prior to decapitation (EGG, SRI) or cervical dislocation (CWR). The animals were deprived of food 12-24 hr immediately preceding death; otherwise food and water were provided ad libitum. The livers were removed aseptically, washed in ice-cold 0.15 M KCl, and minced and homogenized (3 ml of 0.15 M KC1 per gm of wet tissue) in a Potter-Elvehjem apparatus with a Teflon pestle. CWR initially used a Waring blender, but switched to a Potter-Elvehjem apparatus. The S-9 fraction was obtained by centrifugation of the liver homogenate for 10 min at 9,000 g at 4°C. The S-9 mix was prepared immediately prior to each assay.
- Volumes of S9 mix:
Per milliliter:
S-9 fraction 0.10 ml
0.04 M MgC12 0.02 ml
1.65 M KC1 0.02 ml
0.04 M NADP 0.10 ml
0.05 M glucose-6-phosphate 0.10 ml
1.0 M NaH2P04, (pH 7.4) 0.10 ml
Distilled water 0.56 ml

Test concentrations with justification for top dose:

0, 100, 333, 1000, 3333, 10000 ug/plate

Vehicle / solvent:

Water

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

Potassium chloride

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

sodium azide

other: -4-nitro-o-phenylenediamine for TA98; - with metabolic activation: 2-aminoanthracene (all strains).

Details on test system and experimental conditions:

NUMBER OF REPLICATIONS:
- Number of cultures per concentration: 3

METHOD OF TREATMENT/ EXPOSURE:
- preincubation test

TREATMENT AND HARVEST SCHEDULE:
- Preincubation period: 20 min
- Exposure duration: 48 h

FOR GENE MUTATION:
- Ames test

Evaluation criteria:

1) Mutagenic response: a dose-related, reproducible increase in the number of revertants over background, even if the increase was less than twofold
2) nomutagenic response: when no increase in the number of revertants was elicited by the chemical
3) questionable response: when there was an absence of a clear-cut dose-related increase in revertants; when the dose-related increases in the number of revertants were not reproducible;
or when the response was of insufficient magnitude to support a determination of mutagenicity

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 10000 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 10000 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 10000 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 10000µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

GENOTOXIC EFFECTS:
- With metabolic activation: negative
- Without metabolic activation: negative

PRECIPITATION CONCENTRATION:
- No precipitate observed

CYTOTOXIC CONCENTRATION:
- With metabolic activation: 10000 ug/plate
- Without metabolic activation: 10000 ug/plate

Strain: TA1535

Dose	No Activation (Negative)		10% HLI (Negative)		10% RLI (Negative)
Protocol	Preincubation		Preincubation		Preincubation
ug/Plate	Mean	± SEM	Mean	± SEM	Mean	± SEM
0	33	2.3	11	2.6	15	0.3
100	30	4.9	10	2.3	10	3
333	25	3.5	9	1.7	11	3.8
1000	30	2.7	11	2	10	0.9
3333	7s	4.1	15	3.5	18	1.7
10000	0s	0	0s	0	0s	0
Positive Control	342	42.1	245	10.7	178	24.1

 

Strain: TA100

Dose	No Activation (Negative)		10% HLI (Negative)		10% RLI (Negative)
Protocol	Preincubation		Preincubation		Preincubation
ug/Plate	Mean	± SEM	Mean	± SEM	Mean	± SEM
0	146	10.4	121	2.7	121	6.5
100	118	5.1	114	8.6	136	11.5
333	129	9.4	132	5.7	116	10.3
1000	108	5.2	143	9.4	108	9.3
3333	118	9	121	16.9	94	11.1
10000	0s	0	0s	0	41s	20.5
Positive Control	377	8.7	966	42.3	456	24.8

 

Strain: TA98

Dose	No Activation (Negative)		10% HLI (Negative)		10% RLI (Negative)
Protocol	Preincubation		Preincubation		Preincubation
ug/Plate	Mean	± SEM	Mean	± SEM	Mean	± SEM
0	16	2	26	5.7	25	1.9
100	17	1.7	32	2.3	27	3.5
333	13	3.1	32	3.2	25	0.6
1000	12	3.2	34	4.7	32	2.3
3333	8s	4.3	0s	0	23	4.5
10000	t		t		0s	0
Positive Control	475	108.7	764	21.3	326	10.7

 

Strain: TA1537

Dose	No Activation (Negative)		10% HLI (Negative)		10% RLI (Negative)
Protocol	Preincubation		Preincubation		Preincubation
ug/Plate	Mean	± SEM	Mean	± SEM	Mean	± SEM
0	5	1.5	5	1.5	6	1.7
100	11	2.1	7	1.2	6	1
333	5	1.3	4	1	7	1.2
1000	6	3.2	7	1.2	4	0.7
3333	4	1.7	0s	0	3	0.7
10000	0s	0	t		0s	0
Positive Control	350	41.7	406	11.5	135	8.7

  

Abbreviations:
RLI = induced male Sprague Dawley rat liver S9
HLI = induced male Syrian hamster liver S9
s = Slight Toxicity; p = Precipitate; x = Slight Toxicity and Precipitate; T = Toxic; c = Contamination

Conclusions:

Based on the results of this publication, the test substance is negative in the Salmonella/microsome preincubation assay with and without metabolic activation.

Executive summary:

The test substance was evaluated for mutagenicity in the Salmonella/microsome preincubation assay using a standard protocol approved by the National Toxicology Program. Doses of 0, 100, 333, 1000, 3333 and 10000 ug/plate were tested in four Salmonella typhimurium strains (TA98, TA100, TA1535, and TA1537) in the presence and absence of Aroclor-induced rat or hamster liver S9. The test substance was evaulated as negative in all experiments.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

Based on a well documented study (Seiler, 1981), which meets generally accepted scientific principles and which is acceptable for assessment, the test substance is a Noncarcinogen in mice in a DSI-test.

Link to relevant study records

Reference

Endpoint:

in vivo mammalian cell study: DNA damage and/or repair

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

- male mice were used
- on the eve of test day: animals received injection of 18,5 kBq (0,5 µCi) (methyl-14C)-thymidine (subcuaneously in the back)
- the next day: prelabeled animals are randomly assigned to test and control groups (receive test substance i.p.)
- 3 hours later: again injection with labeled thymidine subcutaneously (10 µL = 0,37 MBq (10µCi) (methyl-14C)-thymidine
- 45 min later: i.p. injection of 3,0 mg unlabeled thymidine in 0,2 ml physiological saline (provides for a 5x10^4-fold dilution of the radioactive thymidine)
- 30 min later: mice were sacrified and their testes excised
- testes were transferred into 5% trichloroacetic acid (TCA), homogenized and centrifuged
- the pellet was washed twice in 5% TCA, resuspended in fresh 5% TCA, heated for 30 min at 95°C for DNA hydrolysis, cooled and centrifuged
- DNA content was determined photometrically
- radioactivity was determined by liquid scintillation counting

GLP compliance:

not specified

Species:

mouse

Strain:

not specified

Sex:

male

Route of administration:

intraperitoneal

Duration of treatment / exposure:

3 hours

Frequency of treatment:

single application

Dose / conc.:

5 mg/kg bw/day

Dose / conc.:

15 mg/kg bw/day

Dose / conc.:

50 mg/kg bw/day

No. of animals per sex per dose:

no data

Control animals:

yes

Statistics:

nonparametric test (Wilcoxon-rank-test or equivalent)

Sex:

male

Genotoxicity:

negative

Toxicity:

not specified

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

not specified

Table 1: DSI Test Results of Ethylamine

Compound	Dose (mg/kg)	%DSI
Ethylamine	5 i.p.	0
	15	0
	50	5,6

Conclusions:

Based on the DSI Test results of this publication, the test substance is a Noncarcinogen in mice.

Executive summary:

Male mice were treated with the test substance intraperitoneal. Three dose levels (5, 15, 50 mg/kb bw) were investigated. The results show that the test substance is a Noncarcinogen under the test conditions chosen.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

The test substance was evaluated for mutagenicity in the Salmonella/microsome preincubation assay (Mortelmans, 1986) using a standard protocol approved by the National Toxicology Program. Doses of 0, 100, 333, 1000, 3333 and 10000 ug/plate were tested in four Salmonella typhimurium strains (TA98, TA100, TA1535, and TA1537) in the presence and absence of Aroclor-induced rat or hamster liver S9. Also an in vivo DSI-test was performed in male mice (Seiler, 1981). Three concentrations of the test substance were tested (5, 15, 50 mg/kg bw/d) and showed no DNA synthesis inhibition.

Further in vitro Ames tests (Hussein, 1969; Szybalski, 1958; Air products, 1977) and a sister chromatide exchange (SCE) test (Speit, 1988) were performed. The test substance was evaulated as negative in all experiments except the SCE assay, where the test substance is described as a SCE inducer. However, this SCE assay has significant methodological deficiencies as no controls were investigated.

Taken all studies into account, the test substance is evaluated as not mutagenic.

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) 1272/2008. No adverse findings on genotoxicity was observed in the Salmonella/microsome preincubation assay or in an in vivo DSI test. As a result the substance is not considered to be classified for mutagenicity under Regulation (EC) No. 1272/2008, as amended for the thirteenth time in Regulation (EC) No 2018/1480.