2-(1-oxa-4-azaspiro[4.5]dec-4-yl)ethyl methacrylate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Initiation date Oct.-30-1986 (dose range finding) and Nov.-19-1986 Completion date Nov:-06-1986 (dose range finding) and May:-14-1986 (microscopic examination)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-(1-oxa-4-azaspiro[4.5]dec-4-yl)ethyl methacrylate

EC Number:

224-116-8

EC Name:

2-(1-oxa-4-azaspiro[4.5]dec-4-yl)ethyl methacrylate

Cas Number:

4203-89-8

Molecular formula:

C14H23NO3

IUPAC Name:

2-{1-oxa-4-azaspiro[4.5]decan-4-yl}ethyl 2-methylprop-2-enoate

Test material form:

liquid

Specific details on test material used for the study:

Purity: > 99%; major impurity p-methoxyphenol (100 ppm)
Batch no: 860930-DT4
Solubility: Soluble in ethanol and toluene, decomposes in water
Storage: At ambient temperature in the dark in the presence of silica gel
Stability: Stable in the absence of moisture
Appearance: Clear slightly yellow liquid

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Fourty young adult rats of the Wistar strain (approximately 7 weeks old upon arrival, SPF-quality, randomly bred) were obtained from Charles River Wiga GmbH, Sulzfeld, FRG (instead from Iffa-Credo, Brussels, Belgium as mentioned in the study protocol). Date of arrival at the animal house : October 21, 1986 . The animals were identified by means of ear tags. The quarantine period was 7 days. At least five days prior to dosing the animals were individually housed in polycarbonate cages (acclimation period). The body weights of the males on day 0 ranged from 327 to 424 g and those of the female s from 218 to 269 g: The bedding material, purified sawdust (Woody Clean), was received from The Broekman Institute, Someren, The Netherlands. The animals had free access to tap-water and standard laboratory animal diet (RMH-B, pellet diameter 10 mm), which was obtained from Hope Farms, Woerden, The Netherlands. The animal room temperature was maintained at 18-21°C (on several occasions the temperature ranged between 18-19°C for a period ranging from 6 -40 hours which was below 22 ± 3 °C as mentioned in the study protocol) and the relative humidity at 49-70 percent: The artificial light sequence was 12 hours light, 12 hours dark: Feed was withheld overnight prior to dosing until approximately 3.5-4.5 hours after administration of the test substance.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

On the day of dosing undiluted test substance was administered as a single dose using a stainless steel stomach cannula. The dose volume (ml/kg body weight) was calculate d as follows: dose (g/kg body weight)/specific gravity (g/ml). The specific gravity used was 1.04 g/ml. The day of dosing was considered as day 0.

Doses:

3200, 4200, 5600 and 7400 mg/kg body weight

No. of animals per sex per dose:

Dose range-finding investigation: 1 male and 1 female per dose
Limit study: 5 males and 5 females per dose
Full study: 5 males and 5 females per dose

Control animals:

no

Details on study design:

Dose range finding investigation:
Each dose group, comprising one male and one female, receives a single dose of the test substance. The dose levels are determined based on the availability of toxicity data. Generally, the study duration is 7 days; however, this may be changed if considered necessary.
Limit study:
One dose group, comprising five males and five females, receives a dose of 5000 mg/kg body weight. The study duration is 14 days; however, this period may be extended when considered necessary (determined by the toxic reaction, rate of onset and length of recovery period).
Full study:
At least three dose levels are selected in such a manner that a range of responses to treatment will be elicited and that the generated data will be sufficient to permit adequate assessment of the LD50 value. Each dose group comprises five males and five females. The study duration is 14 days; however, this period may be extended when considered necessary (determined by the toxic reactions, rate of onset and length of recovery period).

PERIODICAL AND TERMINAL DETERMINATIONS (OBSERVATIONS):
During cage-side observations particular attention is paid to changes in the skin, fur, eyes and mucous membranes, as well as to behavioural pattern, tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma. For the main study cage-side observations are performed once every two hours on the day of dosing and once every day thereafter. For the dose range finding investigation cage-side observations are performed frequently on the day of dosing and once every day thereafter. If any animal dies during the study the time of death is recorded as precisely as possible. With exception of weekends and holidays a daily mortality check is performed (usually in the evening).
Individual body weights of the animals are determined on the day of dosing, weekly thereafter and at death (if found dead 24 hours or more following dosing). At the end of the study all surviving animals are sacrificed by C02- asphyxiation and subjected to autopsy. Gross morphological changes are recorded. Abnormal organs and tissues of animals surviving more than 24 hours will be subjected to histopathological examination if it is considered that such examination will yield additional useful information.

Results and discussion

Preliminary study:

In order to establish an appropriate dose range four groups of animals, each comprising 1 male and 1 female, were dosed with an oral dose of the test substance at 1300, 2400, 4200 and 5600 mg/kg body weight, respectively. Mortalities occurred in the 5600 mg/kg body weight (both animals) dose group. Signs of toxicity were lethargy, teary eyes and haematuria. The observation period was 7 days.

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LD50

Effect level:

3.5 other: g/kg bw

Based on:

test mat.

95% CL:

>= 2.6 - <= 4

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

3.6 other: g/kg bw

Based on:

test mat.

95% CL:

>= 1.3 - <= 4.5

Effect levels 3

Sex:

female

Dose descriptor:

LD50

Effect level:

3.4 other: g/kg bw

Based on:

test mat.

Mortality:

The incidence of mortalities for the sexes combined from low to high dose group was 4, 7, 10 and 10. There was no evident sex related effect: All deaths occurred within 4 days.

Clinical signs:

other: Signs of toxicity were body weight loss for animals found dead. Other signs of toxicity were lethargy, stagger, teary eyes, noisy respiration, laboured respiration, slow respiration, tremors, emaciation, comatose, rough coat, pale skin and blood (crusts)

Gross pathology:

Macroscopic examination of animals at necropsy revealed autolysis; yellow, watery or bloody stomach content, slimy covering of the stomach mucosa, enlarged stomach, hyperaemia, erosion or haemorrhage of the stomach, firm white/grey areas in the stomach; watery, slight green watery, bright slimy, yellow or bloody intestinal content, gas accumulation in the intestines, haemorrhage of the intestines; pink or dark red liver; small spleen; enlarged kidneys, grey/green discolouration of the kidneys; petechiae or haemorrhage of the thymus; swollen lungs, hyperaemia of the lungs and haemorrhage of the lungs. Microscopic examination of the stomach of one female of the 4200 mg/kg group revealed an ulcus.

Any other information on results incl. tables

Sex	LD50 Value (mg/kg body weight)	95% Confidence Interval^b.)(mg/kg body weight)	Slope	G^a.)
Combined	3495	2641-3997	9.545	0.4345
Males	3586	1336-4490	8.905	0.8002
Females	3415	NC^c.)	10.746	1.0244

a) G<1, 95 % confidence intervalvalid according to Finney.

b) Calculated with U-distribution.

c) Not calculated,G> 1.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

LD50 = 3500 mg/kg bw

Conclusions:

Four groups of Wistar rats, each comprising 5 males and 5 females, received a single oral dose of Nourycryl MA 128 at 3200, 4200, 5600 and 7400 mg/kg body weight, respectively. The incidence of mortalities for the sexes combined from low to high dose group was 4, 7, 10 and 10. There was no evident sex related effect. All deaths occurred within 4 days of dosing. Signs of toxicity were body weight loss for animals found dead. Group mean body weight for survivors were restored by the end of the study. For surviving a nimals these signs were reversible since as of day 8 no more abnormalities were observed during the 14-day observation period: Major test substance related gross abnormalities at necropsy were: haemorrhage of the stomach, intestines, thymus and lungs; abnormal stomach and/or intestinal content; enlarged or grey/green discolouration of the kidneys and a pink or dark red liver. Microscopic examination of the stomach of one female of the 4200 mg/kg group revealed an ulcus. The LD50 value for the sexes combined amounted to approximately 3.5 g/kg body weight (95 % confidence interval 2.6-4.0 g/kg body weight): The LD50 value for males alone amounted to approximately 3.6 g/kg body weight and for females alone was estimated at 3.4 g/kg body weight.

Executive summary:

Four groups of Wistar rats, each comprising 5 males and 5 females, received a single oral dose of Nourycryl MA 128 at 3200, 4200, 5600 and 7400 mg/kg body weight, respectively. The incidence of mortalities for the sexes combined from low to high dose group was 4, 7, 10 and 10. There was no evident sex related effect. All deaths occurred within 4 days of dosing. Signs of toxicity were body weight loss for animals found dead. Group mean body weight for survivors were restored by the end of the study. For surviving animals these signs were reversible since as of day 8 no more abnormalities were observed during the 14-day observation period: Major test substance related gross abnormalities at necropsy were: haemorrhage of the stomach, intestines, thymus and lungs; abnormal stomach and/or intestinal content; enlarged or grey/green discolouration of the kidneys and a pink or dark red liver. Microscopic examination of the stomach of one female of the 4200 mg/kg group revealed an ulcus. The LD₅₀ value for the sexes combined amounted to approximately 3.5 g/kg body weight (95 % confidence interval 2.6-4.0 g/kg body weight): The LD₅₀ value for males alone amounted to approximately 3.6 g/kg body weight and for females alone was estimated at 3.4 g/kg body weight.