N-Ethylaniline

N-エチルアニリン

CAS No. 103-69-5

Molecular formula: C8H11N Molecular weight: 121.20

ABSTRACT

The single dose toxicity test revealed LD50 values of 382 mg/kg for males and of 553 mg/kg for females.

　In the repeat dose toxicity test, hemolytic anemia accompanied by methemoglobinemia and formation of erythrocytic Heinz bodies, shortening of prothrombin time and increases of liver and spleen weights were observed in both sexes in a dose-related fashion. Histopathological examination revealed hemosiderosis of the spleen, liver and kidney, increased erythropoiesis in the bone marrow, spleen and liver, and decreased lymphocytes in the marginal zone of the splenic lymph follicles both sexes at a doses of 5 mg/kg and above demonstrated a tendency for disappearance. All changes related to the test substance disappeared or after a 14-day recovery period. The NOELs are considered to be 1 mg/kg/day for both sexes.

　N-Ethylaniline was not mutagenic in Salmonella typhimurium TA100, TA98, TA1535, TA1537 and Escherichia coli WP2 uvrA.

　This chemical substance induced structural chromosomal aberrations in CHL/IU cells at the highest concentration (10 mM = 1.1 mg/ml) after 6-hr treatment without exogenous metabolic activation. Polyploid cells were not induced under the present experimental conditions.

SUMMARIZED DATA FROM THE STUDIES

1. Single Dose Oral Toxicity1)

Purity	:	99.6%
Test species/strain	:	Rat/Crj:CD (SD)
Test method	:	OECD Guideline 401
Dosage	:	0 (vehicle), 240, 300, 375, 469, 586, 732 mg/kg
Number of animals	:	Males, 5; females, 5/group
GLP	:	Yes

　Test results:

　Treatment-related clinical signs were as follows : decrease of locomotor activity, ptosis, deep respiration, cyanosis, brown-colored urine and pale skin. Body weights in treated groups were lower than those of the control group. At autopsy, tissues and organs of dead animals were colored brownish, especially the spleen. Bleeding spots were detected in the gastric mucosa.

　LD50 : Males, 382 mg/kg; females, 553 mg/kg

2. Repeat Dose Toxicity1)

Purity	:	99.6%
Test species/strain	:	Rat/Crj:CD (SD)
Test method	:	Guideline for 28-day Repeat Dose Toxicity Testing of Chemicals (Japan)
Route	:	Oral (gavage)
Dosage	:	0 (vehicle), 1, 5, 25, 125 mg/kg/day
Number of animals	:	Males, 6; females, 6/group
Vehicle	:	Sesame oil
Administration period	:	Males and females, 28 days
Terminal kill	:	Males and females, day 29 or 43
GLP	:	Yes

　Test results:

　Signs of cyanosis, brown-colored eyeballs and urine, pale skin were observed in both sexes at a dose of 125 mg/kg. The 125 mg/kg males showed an inhibition of body weight gain and a decrease of food consumption. Additionally, obvious hemolytic anemia accompanied by methemoglobinemia and formation of erythrocytic Heinz bodies, shortening of prothrombin time and increases of liver and spleen weights were observed in both sexes in a dose-related fashion. Significant increases of total serum bilirubin and potassium in both sexes and of albumin and a decrease of sodium in males were detected at a dose of 125 mg/kg. An increase of potassium was also detected in males at a dose of 25 mg/kg. Blackish brown-colored livers and kidneys, and blackish and enlarged spleens were observed in 125 mg/kg males and females at necropsy. Histopathologically, hemosiderosis in the spleen, liver and kidney, lipofuscin deposition in the kidney, increased erythropoiesis in the bone marrow, spleen and liver, and decreased lymphocytes in the marginal zone of the splenic lymph follicles were observed in both sexes given a dose of 5 mg/kg or above. All changes related to the test substance disappeared or demonstrated tenderly to disappear after a 14-day recovery period.The NOELs are considered to be 1 mg/kg/day for both sexes.

3. Genetic Toxicity

3-1 Bacterial test2)

Purity	:	99.6%
Test species/strains	:	S.typhimurium TA100, TAl535, TA98, TA1537
		E. coli WP2 uvrA
Test methods	:	Guidelines for Screening Mutagenicity Testing of Chemicals (Japan)
Procedures	:	Plate incorporation method
Solvent	:	DMSO
Positive controls	:	-S9 Mix, AF-2 (TA100, WP2, TA98), sodium azide (TA1535) and 9-aminoacridine (TA1537) +S9 Mix, 2-aminoanthracene (all strains)
Doses	:	0, 78.13, 156.3, 312.5, 625, 1250 and 2500 μg/plate
S-9	:	Rat liver, induced with phenobarbital and 5,6-benzoflavone
Plates/test	:	3
Number of replicates	:	2
GLP	:	Yes

　Test results:

　Minimum concentration of test substance at which toxicity was observed:

　Toxicity was observed at a concentration of 250 μg/plate with or without metabolic activation.

　Genetic effects :

S. typhimurium TA100, TA1535, TA 98, TA1537

	+	?	-
without metabolic activation:	[ ]	[ ]	[*]
with metabolic activation:	[ ]	[ ]	[*]

E. Coli WP2 uvrA

	+	?	-
without metabolic activation:	[ ]	[ ]	[*]
with metabolic activation:	[ ]	[ ]	[*]

3-2 Non-bacterial in vitro test (chromosomal aberration test)2)

Purity	:	99.6%
Type of cell used	:	Chinese hamster lung (CHL/IU) cells
Test method	:	Guidelines for Screening Mutagenicity Testing of Chemicals (Japan)
Solvent	:	Dimethyl sulfoxide
Positive controls	:	-S9, Mitomycin C +S9, Cyclophosphamide
Doses	:	-S9 (continuous treatment):0, 0.3, 0.6, 1.1 mg/ml -S9 (short-term treatment):0, 0.3, 0.6, 1.1 mg/ml +S9 (short-term treatment):0, 0.3, 0.6, 1.1 mg/ml
S-9	:	Rat liver, induced with phenobarbital and 5,6-benzoflavone
Plates/test	:	2
GLP	:	Yes

　Test results:

　Cytogenetic effects were seen as follows.

　In the highest concentration group (1.1 mg/ml) with the short-term treatment without metabolic activation, 25.5% cells demonstrated structural chromosomal aberrations. In the mid concentration group (0.6 mg/ml) after 24-hr continuous treatment, cells with structural chromosomal aberrations were marginally induced (5.5% including gap). Cytotoxicity was observed in the high concentration groups (1.1 mg/ml) with 24- and 48-hr continuous treatments and short-term treatment with metabolic activation.

Lowest concentration producing cytogenetic effects in vitro:

without metabolic activation (continuous treatment )	:	0.6 mg/ml (clastogenicity)
without metabolic activation (short-term treatment)	:	1.1 mg/ml (clastogenicity)

　Genotoxic effects:

	clastogenicity			polyploidy
	+	?	-	+	?	-
without metabolic activation:	[*]	[ ]	[ ]	[ ]	[ ]	[*]
with metabolic activation:	[ ]	[ ]	[*]	[ ]	[ ]	[*]

1)	The tests were performed by the Research Institute for Animal Science in Biochemistry and Toxicology, 3-7-11 Hashimotodai, Sagamihara-shi, Kanagawa 229, Japan.　Tel　+81-427-62-2775　Fax　+81-427-62-7979
2)	The tests were performed by the Hatano Research Institute, Food and Drug Safety Center, 729-5 Ochiai, Hadano-shi, Kanagawa, 257, Japan.　Tel　+81-463-82-4751　Fax　+81-463-82-9627