(E)-1-(2,4,4-trimethyl-2-cyclohexen-1-yl)-2-buten-1-one

Endpoint summary

Description of key information

Oral (OECD 401), rat: LD50: > 2000 mg/kg bw (limit test)

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 Aug - 13 Sep 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Version / remarks:

24 Feb 1987

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Version / remarks:

EEC directive 92/69/EEC (July 31, 1992)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Niedersächsisches Umweltministerium, Hannover, Germany

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

other: Hsd/Cpb:WU

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Females nulliparous and non-pregnant: not specified
- Weight at study initiation: 230 - 252 g (males) and 155 - 171 g (females)
- Fasting period before study: 16 h before administration and 3 -4 h after administration
- Housing: up to 5 animals per cage per sex, in Makrolon type III cages on LIGNOCEL bedding
- Diet: pelleted rat diet (Ssniff R-Alleindiät, Ssniff Spezialdiäten GmbH, Soest, Germany), ad libitum
- Water: drinking water, ad libitum
- Acclimation period: 6 days (range-finding study), 7 days (main study, females), 14 days (main study, males)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 2.11 mL/kg bw

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

Range-finding test: 2 females
Main study: 5 males and 5 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were examined 10 min, 1 h, 2 h, 6 h and 24 h after treatment and thereafter once daily up to Day 14. Body weights were recorded immediately before treatment (Day 0) and on Days 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, gross pathology

Preliminary study:

No mortility occured in the range-finding test.

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

1/5 males and 0/5 females died

Clinical signs:

other: slight diarrhea in 5/5 males 24 h after treatment, fully reversible on Day 3; slight squatting position and slight piloerection in 1/5 female 24 h after treatment, fully reversible within 48 h.

Gross pathology:

In the animal found dead, test substance related findings of extreme redness of the gastric mucous membrane was observed.
In surviving animals, an adhesion of the stomach to other organs was found, mainly to the spleen which was enlarged in most animals. Additionally, particles of probably separated and indurated tissue portions were observed in the stomach.

Table 1. Results of the acute oral toxicity study in rats.

Dose level (mg/kg bw)	Mortalities	Clinical signs
males
2000	1/5	5/5
females
2000	0/5	1/5

Interpretation of results:

other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008

Conclusions:

In this acute oral toxicity study in male and female rats a LD50 value of > 2000 mg/kg bw was found.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.5, of Regulation (EC) No 1907/2006.

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The acute oral toxicity of the test substance was assessed in a study according to OECD Guideline 401 and in compliance with GLP (1995). In this study, 1/10 animals died at 2000 mg/kg bw. Clinical signs of slight diarrhea were observed in 5/5 males 24 h after treatment, fully reversible on Day 3. Additionally, slight squatting position and slight piloerection were observed in 1/5 females 24 h after treatment, fully reversible within 48 h.Thus, a LD50 of > 2000 mg/kg bw was derived.

Justification for classification or non-classification

The available data on acute oral toxicity do not meet the criteria for classification according to Regulation (EC) 1272/2008, and are therefore conclusive but not sufficient for classification.