2,6-diisopropylnaphthalene

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 Jul - 04 Aug 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,6-diisopropylnaphthalene

EC Number:

246-045-1

EC Name:

2,6-diisopropylnaphthalene

Cas Number:

24157-81-1

Molecular formula:

C16H20

IUPAC Name:

2,6-diisopropylnaphthalene

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Ace Animals, Inc., Boyertown, PA, USA
- Females nulliparous and non-pregnant: yes
- Age at study initiation: young adults
- Weight at study initiation: 218 - 230 g (males), 161 - 170 g (females)
- Fasting period before study: approx. 24 h
- Housing: Singly housed in suspended stainless steel cages with mesh floors
- Diet: Purina Rodent Chow #5012, no further details given
- Water: Filtered tap water, ad libitum
- Acclimation period: 13 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.9 - 22.8
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: From: 21 July To: 04 Aug 1997

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 50% (w/w)
- Amount of vehicle (if gavage): no data
- Justification for choice of vehicle: Preliminary solubility testing indicated that suspensions in excess of 50% were too viscous to be administered.

MAXIMUM DOSE VOLUME APPLIED: 2.4 mL

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: 1 and 3 h post dosing, at least once daily until termination
- Frequency of weighing: prior to dosing, Day 7 and Day 14 before termination or after death
- Necropsy of survivors performed: yes
- Observations: Gross evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central nervous systems, somatomotor activity and behavior pattern. Particular attention to tremors, convulsions, salivation, diarrhea and coma.
- Necropsy: Tissues and organs of the thoracic and abdominal cavities.

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

act. ingr.

Mortality:

One female died 6 days after test substance administration.

Clinical signs:

Clinical signs included hunched posture, hypoactivity, piloerection, reduced fecal volume, facial and/or ano-genital staining. The surviving animals recovered from clinical signs by Day 7.

Body weight:

All surviving animals gained bodyweight over the 14-day observation period.

Gross pathology:

Gross necropsy of the female found dead on Day 6 revealed discoloration of the lungs and intestines. Gross necropsy findings for the surviving animals at terminal sacrifice were generally unremarkable.

Any other information on results incl. tables

Table 1: Individual bodyweight, dosage and mortality

Animal no.	Sex	Bodyweight [g]			Dose [mL]	Mortality
		Initial	Day 7	Day 14		Day	Bodyweight [g]
8762	M	227	263	334	2.4	E	--
8763	M	230	248	324	2.4	E	--
8764	M	218	257	317	2.3	E	--
8765	M	221	250	307	2.3	E	--
8766	M	218	254	302	2.3	E	--
8767	F	167	204	226	1.7	E	--
8768	F	162	--	--	1.7	6	152
8769	F	161	189	214	1.7	E	--
8770	F	170	190	214	1.8	E	--
8771	F	163	202	222	1.7	E	--

M: Male

F: Female

E: Euthenised on Day 14

Table 2: Individual cage-side observations

Animal no.	Findings	Day of occurrence
8762 (M)	Active and healthy Hypoactivity Hunched posture Piloerection	0(1-3 h), 5-14 0(21 h)-2 0(21 h)-3 0(21 h)-4
8763 (M)	Active and healthy Piloerection, hunched posture Hypoactive Facial staining Ano-genital staining	0(1-3 h), 7-14 0(21 h)-4 1-2 2 2-6
8764 (M)	Active and healthy Piloerection	0(1-21 h), 3-14 1-2
8765 (M)	Active and healthy Hypoactive Hunched posture Piloerection Facial staining Ano-genital staining	0(1-3 h), 6-14 0(21 h)-2 0(21 h)-3 0(21 h)-4 2 2-3, 5
8766 (M)	Active and healthy Hunched posture Piloerection Hypoactive Facial staining	0(1-3 h), 6-14 0(21 h)-4 0(21 h)-5 1-2 2
8767 (F)	Active and healthy Hypoactive Piloerection, hunched posture Reduced vecal volume	0(1-3 h), 6-14 0(21 h) 0(21 h)-4 2, 5
8768 (F)	Active and healthy Piloerection Hunched posture, reduced fecal volume Hypoactive Dead	0(1-21 h) 1-5 2-5 3-5 6
8769 (F)	Active and healthy Piloerection Hunched posture Hypoactive Reduced fecal volume	0(1-21 h), 6-14 1-3 1-4 2-3 2-5
8770 (F)	Active and healthy Piloerection, hunched posture Facial staining, hypoactive Reduced fecal volume Ano-genital staining	0(1-3 h), 4-5, 7-14 0(21 h)-3 1 1-3, 6 6
8771 (F)	Active and healthy Piloerection Hunched posture Reduced fecal volume	0(1-21 h), 6-14 1-3 2-3 2-5

M: Male

F: Female

Table 3: Individual necropsy observations

Animal no.	Tissue	Findings
Males
8762-8766	Lungs	Slightly red*
Females
8767, 8769-8771	Lungs	Slightly red*
8768	Lungs Intestines	Slightly red* Red

*: Customarily seen with CO₂ inhalation, due to euthanasia procedure.

Applicant's summary and conclusion

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 rats a LD50 value of > 5000 mg/kg bw was determined.