N,N-Bis(2-hydroxyethyl)-C12-18(even numbered, C18 unsaturated) alkyl-1-amine oxides

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

March 2012-december 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

N,N-Bis(2-hydroxyethyl)-C12-18(even numbered, C18 unsaturated) alkyl-1-amine oxides

EC Number:

942-293-6

Molecular formula:

not applicable

IUPAC Name:

N,N-Bis(2-hydroxyethyl)-C12-18(even numbered, C18 unsaturated) alkyl-1-amine oxides

Test material form:

liquid: viscous

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on mating procedure:

The mating began 2 weeks after the initiation of treatment with one female and one male of the same dose group (1:1 mating) in a single cage. Females remained with the same male until copulation occured or up to two weeks.
A vaginal smear was prepared daily during the mating period and stained with 1% aqueous methylene blue solution. The smears were examined with a light mictroscope, the presence of vaginal plug or sperm in the vaginal smear was considered as evidence of copulation. Sperm positive females were caged individually. Mating pairs were clearly identified in the data, mating of siblings was avoided.

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

28 days for males and up to 54 days for females (14 days pre-mating + up to 14 days for mating + gestation + 4 days of lacation)

Frequency of treatment:

once per day

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 12.5, 50, 200
Basis:
nominal in water

No. of animals per sex per dose:

12

Control animals:

yes, concurrent vehicle

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

effects observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

limited to organs with macroscopic changes

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

effects observed, treatment-related

Details on results (P0)

ORTALITY
At 200 mg/kg bw: one male animal was found dead after 22 treatments. Decreased activity, red liquid on the nose, piloerection and hunched back position were noted prior to the death. Upon histopathological investigation, malignant lymphoma that affected the spleen, thymus, liver, lungs and adrenal glands was considered to be cause of death.

Clinical signs
At 200 mg/kg bw, one surviving male displayed noisy respiration, piloerection and lack of grooming, and four females exhibited noisy respiration.

BODY WEIGHT AND WEIGHT GAIN
At 200 mg/kg bw, reduced body weight or body weight gain was noted for males and females.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
At 200 mg/kg bw, reduced food consumption was noted for males and females

HAEMATOLOGY
No toxicologically significant effect was found.

CLINICAL CHEMISTRY
No toxicologically significant effect was found.
ORGAN WEIGHTS
No toxicologically significant effect was found.

GROSS PATHOLOGY
At 200 mg/kg bw, thickened/rough surface non glandular mucosa was noted.

HISTOPATHOLOGY: NON-NEOPLASTIC
At 200 mg/kg bw, minimal to mild diffuse parakeratotic hyperkeratosis of the non-glandular stomach was found.

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

50 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: At 200 mg/kg bw, clinical signs and decreased body weight gain was observed.

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings:

not examined

Details on results (F1)

VIABILITY (OFFSPRING)
At 200 mg/kg bw, reduced number of living pubs at the first observation after birth and increased postnatal mortality was found.
At 50 and 12.5, the number of living pubs were reduced when compared to the corresponding control, but the obtained values were within the historical control range and were considered as incidental.

CLINICAL SIGNS (OFFSPRING)
No finding

BODY WEIGHT (OFFSPRING)
The body weight at 200 mg/kg bw was reduced when compared to the corresponding control.

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

50 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: At 200 mg/kg bw, reduced litter size at birth and increased postnatal mortality occured.

Overall reproductive toxicity

Reproductive effects observed:

not specified

Any other information on results incl. tables

Tab 1a: Body weight development for males [g]
Dose group	Day numbers relative to start date
		Pre-mating		Mating
		0	7	14	21	28
Control	Mean	421.25	442.67	436.75	475.33	495.67
	S.D.	16.45	18.24	22.04	25.46	28.57
	N	12	12	12	12	12
12.5 mg/kg bw/day	Mean	421.25	443.42	439.08	475.33	496.58
	S.D.	15.49	14.28	14.32	18.89	20.99
	N	12	12	12	12	12
50 mg/kg bw	Mean	420.75	441.75	437.67	473.25	498.17
	S.D.	13.98	17.80	17.60	17.48	19.93
	N	12	12	12	12	12
200 mg/kg bw/day	Mean	420.92	432.83	422.17*	450.10**	475.91*
	S.D.	14.30	13.87	11.75	24.28	23.07
	N	12	12	12	11	11

 

Tab 1b: Body weight development for females [g]
Dose group		Pre-mating			Gestation				Lactation
		0	7	14	0	7	14	20	0	4
Control	Mean	239.67	251.00	248.89	262.00	297.67	335.78	424.00	330.67	347.56
	S.D.	11.65	12.66	14.73	14.76	17.33	19.47	26.40	23.69	30.53
	N	9	9	9	9	9	9	9	9	9
12.5 mg/kg bw/day	Mean	239.75	246.58	244.17	259.75	287.33	322.75	397.25	313.42	329.33
	S.D.	10.64	12.24	14.44	14.64	15.71	20.04	25.07	24.48	25.66
	N	12	12	12	12	12	12	12	12	12
50 mg/kg bw	Mean	240.73	249.64	245.18	260.00	294.91	329.18	401.36	327.55	335.82
	S.D.	10.26	10.60	13.63	16.53	17.11	23.50	36.75	25.73	30.87
	N	11	11	11	11	11	11	11	11	11
200 mg/kg bw/day	Mean	240.00	247.82	241.36	254.27	280.09	315.18	390.09*	296.91*	291.45**
	S.D.	10.35	13.36	12.45	10.16	20.30	21.82	24.26	29.00	21.64
	N	11	11	11	11	11	11	11	11	11

Tab 2a: Hematology for males
Dose group		Hb	RBC	Hct	MCH	MCV	MCHC	WBC	Neut	Lymph	PTT	PLT	MPV	APTT	Retic
		g/dl	10^12/l	%	pg	g/dl	g/dl	10^9/l	%	%	sec	10^9/l	fl	sec	%
Control	Mean	17.63	9.14	48.61	19.33	53.18	36.30	9.12	21.55	71.46	24.67	868.08	7.88	16.01	1.99
	S.D.	1.08	0.51	2.80	0.89	1.13	1.36	2.64	8.88	9.77	1.31	243.48	1.06	1.71	0.17
	N	12	12	12	12	12	12	12	12	12	12	12	12	12	12
12.5 mg/kg bw/day	Mean	17.24	9.20	48.78	18.78	53.05	35.38*	9.75	17.23	76.58	24.83	948.92	9.28	17.18	2.19
	S.D.	1.00	0.48	3.13	0.74	1.66	0.95	1.82	6.47	7.39	1.34	377.90	4.37	1.65	0.34
	N	12	12	12	12	12	12	12	12	12	12	12	12	12	12
50 mg/kg bw/day	Mean	17.18	9.28	49.09	18.53*	52.93	35.00**	11.25	14.52*	80.48**	24.66	1111.33	9.24*	17.99	2.06
	S.D.	0.78	0.35	2.06	0.64	1.24	0.93	2.70	6.49	6.69	2.38	341.82	2.07	2.70	0.36
	N	12	12	12	12	12	12	12	12	12	12	12	12	12	12
200 mg/kg bw/day	Mean	16.26**	9.20	47.38	17.69**	51.49*	34.34**	10.97	15.72	78.71*	24.19	1076.10	8.37	18.48	1.73
	S.D.	0.42	0.32	1.67	0.48	1.41	0.61	1.88	4.51	5.17	3.25	268.10	0.48	4.98	0.36
	N	10	10	10	10	10	10	10	10	10	10	10	10	10	10

 

Tab 2b: Hematology for females
Dose group		Hb	RBC	Hct	MCH	MCV	MCHC	WBC	Neut	Lymph	PTT	PLT	MPV	APTT	Retic
		g/dl	10^12/l	%	pg	g/dl	g/dl	10^9/l	%	%	sec	10^9/l	fl	sec	%
Control	Mean	16.34	8.67	47.12	18.84	54.33	34.68	4.61	21.10	74.02	23.51	951.78	8.13	18.28	2.49
	S.D.	0.83	0.36	1.86	0.84	1.73	0.61	1.04	5.77	6.01	1.25	269.92	0.61	1.62	0.59
	N	9	9	9	9	9	9	9	9	9	9	9	9	9	9
12.5 mg/kg bw/day	Mean	16.22	8.71	47.03	18.61	53.98	34.45	5.63	14.68	80.72*	23.05	1097.83	8.27	18.39	2.37
	S.D.	0.72	0.31	2.01	0.48	1.36	0.62	2.27	4.16	4.24	2.54	139.50	0.35	2.25	0.51
	N	12	12	12	12	12	12	12	12	12	12	12	12	12	12
50 mg/kg bw/day	Mean	16.17	8.52	46.78	19.00	54.92	34.59	6.40*	21.63	73.22	23.97	1068.82	8.62*	18.36	2.54
	S.D.	0.65	0.36	1.83	0.73	1.50	0.49	1.69	21.87	24.43	1.04	245.42	0.54	1.00	0.51
	N	11	11	11	11	11	11	11	11	11	11	11	11	11	11
200 mg/kg bw/day	Mean	15.67	8.39	45.74	18.71	54.57	34.29	8.46**	15.04	80.49*	24.78	1010.18	8.77*	18.67	2.26
	S.D.	0.44	0.42	1.53	0.58	1.59	0.65	3.28	6.88	7.31	1.71	187.18	0.51	1.73	0.39
	N	11	11	11	11	11	11	11	11	11	11	11	11	11	11

Tab 3: Summary report of effects on reproduction/development
	Dose group
	Control	12.5 mg/kg bw/day	50 mg/kg bw/day	200 mg/kg bw/day
No. of females paired	12	12	12	12
No. of females mated	9	12	11	11
No. of females pregnant	9	12	11	11
No. of dams with living pubs	9	12	11	11
Body weight on GD20 [g]	424	397	401	390*
Body weight on PN4 [g]	348	329	336	291**
Corpora lutea	17.3	15.2	12.6*	15.7
Implantation sites	15.2	13.7	11.3*	13.4
No. of pubs alive at birth	14.7	12.4**	11.2*	9.3**
No. of pubs alive at PN4	14.6	12.1**	11.0*	1.2**

* p < 0.05; ** p <0.01; ***p < 0.001

Applicant's summary and conclusion

Conclusions:

The registration substance was investigated for its reproduction toxicity according to the OECD Guideline 421. The NOAEL of 50 mg/kg bw was derived for systemic toxicity and for reproductive toxicity.

Executive summary:

The registration substance was investigated for its reproduction toxicity according to the OECD Guideline 421. Rats were treated with the registration substance at doses of 12.5, 50 and 200 mg/kg bw.

The generation toxicity on parental animals at 200 mg/kg bw comprised noisy respiration, piloerection, lack of grooming. At this dose, the males exhibited remarkable decreased body weight gain in the pre-mating phasee and females significant body weight decrease in the lactation phase. Further observation included macroscopic and microscopic changes in the stomach at 200 mg/kg bw.

At 200 mg/kg bw, significantly reduced living pub numbers at first observation after birth and increased postnatal mortality was found.

The NOAEL of 50 mg/kg bw was derived for systemic toxicity and for reproductive toxicity.