Nonane

Endpoint summary

Description of key information

Oral LD50 (rat) > 5000 mg/kg bw

 

Inhalation LC50 (rat) = 17000 mg/m³

Dermal LD50 (rabbit) > 2000 mg/kg

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles, acceptable for assessment.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

Limit test with 5000 mg/kg versus 2000 mg/kg as per guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

Limit test with 5000 mg/kg versus 2000 mg/kg as per guideline

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

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 and weighing: observations daily; weighing on initiation and on days 7 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Mortality:

No mortality occurred in any test animal over the 14-day observation period.

Clinical signs:

other: Clinical observations noted one-hour post exposure in 8 of 10 animals included depression, salivation, wheezing, rough coat, and soft feces. Two female rats appeared normal throughout the study. All animals appeared normal from day 2 through termination

Gross pathology:

No abnormal gross pathology findings were noted in any of the animals upon necropsy.

Interpretation of results:

other: Not classified

Remarks:

Criteria used for interpretation of results: other: GHS, EU, 2007

Conclusions:

Based on the study design the test substance, Isooctane, needs not to be classified.

Executive summary:

Based on the study design the test substance, Isooctane, needs not to be classified.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

> 5 000 mg/kg bw

Quality of whole database:

1 key read across study available from a structural analogue

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Basic data given.

Reason / purpose for cross-reference:

reference to same study

Principles of method if other than guideline:

Ten male Sprague-Dawley rats per concentration were exposed to nonane via inhalation at 2414, 3560, 4438, or 5280 ppm for 8 hours.

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Mollegaard A/S, Ll. Skensved, Denmark
- Weight at exposure: 200 g ± 20 %
- Housing: The number of animals in each cage was 4 with a maximum of 4 cages in each inhalation chamber.
- Individual metabolism cages: no
- Diet (e.g. ad libitum): ad libitium except during exposure
- Water (e.g. ad libitum): ad libitium except during exposure
- Acclimation period: 4 to 6 days before the start of exposure


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±1
- Humidity (%): 40-70
- Photoperiod (hrs dark / hrs light): 10/14

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Animals were kept in conically shaped 0.7 cubic metre steel chambers with glass front and walls.
- Method of holding animals in test chamber: a maximum number of 18 animals in each chamber
- System of generating particulates/aerosols: Dynamic exposure was performed by passing high oil-and dust-filtered air under pressure through 4 reservoirs of each containing 0.5 L of the test substance. At an air flow rate of 30-40 L/min an outlet concentration equal to 95% of vapour saturation was achieved. The vapour generating system was located in a water bath. Saturation concentrations of nonane at 20°C were achieved by keeping a constant temperature in the water bath of 22.5°C.
Air from the vapour generating system was introduced at the top of the exposure chamber and drained from the chamber through a perforated bottom outlet.
- Temperature, humidity, pressure in air chamber: 22±1 °C, 40-70%
Air was withdrawn from the inhalation chamber by a ventilation fan creating a negative pressure of 2-5 mm H2O on the inside of the chamber. During exposure the flow of air through the chamber (exposure and control) was 30-40 L/min, corresponding approx. to 3 air changes/hour.


TEST ATMOSPHERE
- Brief description of analytical method used:
Concentration of nonane in the inhalation chamber was monitored automatically every 15 min by on-line gas chromatography. Nonane was detected by a FID detector and quantified by a programmable integrator (Shimadzu C-R3A) which also controlled the frequency and sequence of air sampling.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

8 h

Concentrations:

2414; 3560; 4438; 5280 ppm (corresponding to approx. 12.84; 18.94; 23.61; 28.09 mg/L)

No. of animals per sex per dose:

10

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: During inhalation all animals were observed at 15 and 30 min. intervals. For the first 8 hours after exposure all animals were observed at hourly, then at 2 hours intervals during daytime for 14 consecutive days.
- Necropsy of survivors performed: yes
- Other examinations performed: All animals were subjected to complete necropsy which included examination of the external surface of the body, all orifices, and the cranial, thoracic and abdominal cavities and their contents according to the OECD procedures (OECD 1987). In addition to general activity, acute effects as coordination difficulties, tremor, spasms and lethality were monitored.

Statistics:

Calculations were performed according to the method described by Finney (1964).

Preliminary study:

not applicable

Key result

Sex:

male

Dose descriptor:

LC50

Effect level:

ca. 23.76 mg/L air

Exp. duration:

8 h

Remarks on result:

other: LC50= 4467±189 ppm

Mortality:

0/10 (2414 ppm)
1/10 (3560 ppm)
4/10 (4438 ppm)
9/10 (5280 ppm)
Death occured after 4 hours in the group exposed to 5280 ppm. The length of time before the appearance of death increased in proportion with the decrease of n-nonane concentration in the inhaled air.

Clinical signs:

other: Specific symptoms as tremor, spasms and limb paralysis were observed in animals exposed to nonane in the range from 5280 to 3560 ppm. Specific symptoms occured after 2 hours in the group exposed to 5280 ppm. The length of time before the appearance of spe

Body weight:

All rats exposed to n-nonane showed body weight slightly lower (about 10%) than the control groups. Weight curves indicated the difference to be due to an initial lag in the gain of weight during the 3 first days of observation. From day 3 to 14 the increase in weight was equal for exposed and control animals. However, the difference in total weight persisted throughout the observation.

Gross pathology:

No morphological alterations were observed in heart or kidneys or brain.

Other findings:

- Organ weights:
No significant differences in the weight of the heart, kidneys, liver or brain were found in the 4438 ppm test group (see table 2).
- Histopathology:
Liver:
Microscopically, dilatation of the sinusoids were found in all four animals dying during exposure to 4438 ppm nonane, and 3 of these animals also showed definite though slight fatty changes of the liver cells. In animals surviving exposure or among the controls no such changes were found. Occasionally, single necrotic hepatocytes were encountered in animals both form the experimental groups and among the controls.
Lungs:
The total weight of the lungs in 2 of the animals dying during exposure was approx. twice the weight of the control animals 2.86 g and 2.88 g, compared to 1.26 g. Microscopically, 3 animals showed marked pulmonary oedema. These animals died during exposure and in 2 of them the pulmonary weight was also increased. All exposed animals showed a blue discolouration of the skin during exposure, giving the impression of peripheral cyanosis, and thus cardiopulmonary insufficiency.
Brain:
No macroscopical abnormalities were recorded. In exposed animals which died during exposure, no pathological changes were found. Among the 6 surviving animals, 1 animal showed a few severely damaged neurons of the hippocampus. After 14 days after exposure, extensive changes were observed including rarification of Purkinje cells (cerebellar cortex) and in some instances also a high number of severely damaged neurons were observed in the surviving animals. These changes apparently were not entirely random but seemed to some extent to be segmental. In areas showing massive loss of Purkinje cells there was no obvious glial reaction.
Morphometry of the cerebellum:
The results demonstrated a loss of Purkinje cells in the animals which survived exposure. This is reflected by a reduced density of Purkinje cell profiles along the line which defines the Purkinje cell layer. The reduced density of the visible transections is only in part explained by a reduction of the cellsize, as there is also a significantly reduced number of Purkinje cells per unit area of Purkinje cell layer. The results also indicate a reduction of tissue volume in the other layers of the cerebellum as there was decrease in cerebellar volume relative to the extent of the Purkinje cell layer. There was no clear-cut change of the volume distribution between the different layers. There was no detectable difference between the animals which died during exposure and the controls.
- Other observations:
All animals surviving the 8 hours exposure seemed to recover from their specific symptoms during the entire observation period. The time needed for an apparent full recovery was in proportion with the concentration of n-nonane to which the animal had been exposed. The apparent full recovery time was 7 days for the 5280 ppm group (1 animal), 5 days for the 4438 ppm group (6 animals), 1 day for the 3560 ppm group (9 animals) and 0 -4 hours for the 2414 ppm group (10 animals).

In general, no toxic effects were observed in animals exposed to 2414 ppm of nonane.

Table 1: Concentration of nonane in inhaled air.

A period of 1 hour was needed to achieve steady state air concentration.

chamber concentration [ppm ± SD] (measured at 15 min intervals; generated at 22.5°C)

5280 ± 77*

4438 ± 319*

3560 ± 17

2414 ± 7

* saturation level

Table 2: mean total body weights and organs weights [g ± SD] of rats exposed to 4438 ppm nonane

	No.	Total bw	Brain	Lungs	Heart	Liver	Kidney
Dead animals	4	178.8±11.2	1.81±0.03	2.05±0.95	1.00±0.09	9.93±0.82	2.06±0.18
Surviving animals	6	274.8±25.2	1.87±0.04	1.41±0.11	1.19±0.22	11.88±1.52	2.22±0.18
Control animals	3	201.7±12.6	1.85±0.09	1.26±0.17	1.03±0.15	9.85±0.74	1.87±0.10

Interpretation of results:

other: Not classified

Remarks:

Criteria used for interpretation of results: other: CLP

Conclusions:

Under the conditions of this study, the test substance is not classified.

Executive summary:

Under the conditions of this study, the test substance is not classified.

Reference 2

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions. Only males tested, no control group.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

No control group, only males tested

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

other: Harlan-Wistar

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 57 - 142 g

Route of administration:

inhalation: vapour

Type of inhalation exposure:

not specified

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

TEST ATMOSPHERE
- Brief description of analytical method used: gas chromatography

Analytical verification of test atmosphere concentrations:

not specified

Duration of exposure:

4 h

Concentrations:

4, 8, 16, 32 mg/L (nominal)
1.33, 4.6, 11, 23 mg/L (mean measured)

No. of animals per sex per dose:

16

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, gross pathology, histopathology

Statistics:

Based on mortality during a 14 day observation period, the most probable LC50 with fiducial range was calculated by the Thompson (1947) method of moving averages using the tables by Weil and other unpublished tables.

Key result

Sex:

male

Dose descriptor:

LC50

Effect level:

17 mg/L air (analytical)

95% CL:

14 - 21

Exp. duration:

4 h

Mortality:

23 mg/L: 8/10
11 mg/L: 1/10
4.6 mg/L: 0/10
1.33 mg/L: 0/10

Clinical signs:

other: The response pattern during inhalation of the highest level progressed from early lacrimation, salivation, and coordination loss to clonic and tonic convulsions, tremors and death.

Other findings:

- Histopathology: Micropathological evaluation of tissues taken at necropsy, 14 days following the single 4-hr inhalation periods, revealed no lesion attributable to vapour inhalation.

Interpretation of results:

other: Not classified

Remarks:

Criteria used for interpretation of results: other: CLP

Conclusions:

Taking into account the upper confidence limit of 21000 mg/m³ and the LC50 value of 23760 mg/m³ of the inhalation study of Nilsen et al. (1988), n-nonane has not to be classified. In comparison to OECD 403, advising an exposure of 4 hours, the duration of exposure in the study of Nilsen et al. (1988) was considerably increased. The animals were exposed to n-nonane for 8 hours and therefore the test conditions represented a worst case scenario compared to the study of Carpenter et al. (1978).

According to the criteria of EU and CLP, there is no need for classification, but harmful effects will be expected from the exposure to n-nonane.

Executive summary:

Taking into account the upper confidence limit of 21000 mg/m³ and the LC₅₀ value of 23760 mg/m³ of the inhalation study of Nilsen et al. (1988), n-nonane has not to be classified. In comparison to OECD 403, advising an exposure of 4 hours, the duration of exposure in the study of Nilsen et al. (1988) was considerably increased. The animals were exposed to n-nonane for 8 hours and therefore the test conditions represented a worst case scenario compared to the study of Carpenter et al. (1978).

According to the criteria of EU and CLP, there is no need for classification, but harmful effects will be expected from the exposure to n-nonane.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

17 000 mg/m³ air

Quality of whole database:

2 substance specific weight of evidence studies available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles, acceptable for assessment.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

Only 3 animals per sex versus 5 as per guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

Only 3 animals per sex versus 5 as per guideline

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Type of coverage:

not specified

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bw

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observation continuous, weighing on initiation and days 7 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, dermal score

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No mortality occurred during the 14-day observation period.

Clinical signs:

other: All rabbits appeared normal throughout the study. Very slight dermal erythema was noted in all animals on day 1 after dosing, which persisted in one male and one female on day 3. All erythema had cleared by day 7. Very slight edema was noted in two males

Gross pathology:

No abnormal gross pathology was noted in any rabbits upon necropsy.

Interpretation of results:

other: Not classified

Remarks:

Criteria used for interpretation of results: other: GHS, EU, 2007

Conclusions:

Based on the study design the test substance, Isooctane, needs not to be classified.

Executive summary:

Based on the study design the substance, Isooctane, needs not to be classified.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Quality of whole database:

1 key read across study available from a structural analogue

Additional information

Acute inhalation toxicity data is available for Nonane. Acute oral and dermal toxicity data is available for structural analogue 2,2,4-trimethylpentane. This data is read across to based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

Oral:

2,2,4-trimethylpentane

In a key study (Chevron Phillips Chemicals, 1982), five male and five female Sprague-Dawley rats were exposed, orally by gavage, to a single 5000 mg/kg bw dose of 2,2,4-trimethylpentane. The animals were observed for mortality and clinical signs for the next 14 days. No animals died during the study. Clinical signs of depression, salivation, wheezing, rough coat and soft faeces were observed from one-hour post exposure until day 2. No clinical signs were noted from day 2 to termination of the study. No abnormalities were noted at necropsy. The LD50 was determined to be >5000 mg/kg bw. Under the conditions of this study, 2,2,4-trimethylpentane does not need to be classified.

 

Inhalation:

Nonane

In the non-guideline study (Nilsen et al., 1988), ten male rats per concentration were exposed to nonane via inhalation to 2414, 3560, 4438, or 5280 ppm for 8 hours. Mortality rates by dose were: 0/10 at 2414 ppm, 1/10 at 3560 ppm, 4/10 at 4438 ppm and 9/10 at 5280 ppm. Clinical effects included tremor, spasms and limb paralysis at the highest dose. All surviving animals made an apparent full recovery within 7 days post-exposure. No additional deaths or symptoms were observed during a 14-day observation period. Necropsy showed dilation of the sinusoids and marked pulmonary oedema in the animals that died during treatment. The LC₅₀ was calculated to be 23760 mg/m³ (corresponding to 4467 ± 189 ppm) for an exposure of 8 hours. Based on the LC₅₀ value of 23760 mg/m³, there is no need for classification according to the criteria of EU and CLP. In comparison to OECD 403, advising an exposure of 4 hours, the duration of exposure in the present study was considerably increased since the animals were exposed for 8 hours. Thus, the test conditions represented a worst-case scenario compared to guideline-conforming studies.

 

The study of Carpenter et al. (1978) was conducted similar to OECD 403. Ten male rats per concentration were exposed to nonane via inhalation at 1330, 4600, 11000, or 23000 mg/m³ for 4 hours. Mortality occurred at 11000 mg/m³ (1/10) and 23000 mg/m³ (8/10). No deaths occurred in the lower dose groups. The response pattern during inhalation of the highest level progressed from early lacrimation, salivation, and coordination loss to clonic and tonic convulsions, tremors and death. Micropathological evaluation of tissues taken at necropsy, 14 days following each of the single 4-hr inhalation periods, revealed no lesion attributable to vapor inhalation. The LC₅₀ was determined to be 17000 mg/m³ for an exposure of 4 hours. The 95% confidence limits were 14000 – 21000 mg/m³. Taking into account the upper confidence limit of 21000 mg/m³ and the LC₅₀ of 23760 mg/ m³ of the study from Nilsen et al. (1988), in which the exposure time exceeded the test conditions of OECD 403, nonane does not need to be classified.

 

Dermal:

2,2,4-trimethylypentane 

In a key study (Chevron Phillips Chemicals, 1982), three male and three female New Zealand White rabbits were administered a single, topical 2000 mg/kg bw dose of 2,2,4-trimethylpentane. The test material remained in contact with the skin for 24 hours. Animals were observed for mortality and clinical signs for the next 14 days. No animals died during the study. No clinical signs of toxicity were observed. Very slight dermal erythema was noted in all animals on day 1, and persisted to day 3 in one male and one female. All erythema had cleared by day 7. Very slight oedema was noted in two males and one female on day 1 and cleared by day 3. Epidermal scaling was noted in one female on day 10. No abnormalities were noted at necropsy. The LD₅₀ was determined to be >2000 mg/kg bw. Under the conditions of this study, 2,2,4-trimethylpentane does not need to be classified.

Justification for classification or non-classification

Based on available substance specific and read across data, Nonane is minimally toxic via ingestion where the LD₅₀ is >5000 mg/kg bw, via dermal exposure where the LD₅₀ is >2000 mg/kg bw, and by inhalation where the LC₅₀ is = 17000 mg/m³.  These findings do not warrant classification under the new Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP).

Nonane is classified under EU CLP guidelines as STOT Single Exposure Category 3 (narcosis) based on non-lethal narcotic effects observed in acute inhalation exposure.

 

Nonane is classified under EU CLP guidelines as a Category 1 aspiration hazard based on its physical and chemical properties (hydrocarbon fluid, viscosity ≤ 20.5 mm²/s).