Alkanes, C10-20, straight and linear

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

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

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Published data, information included to support waiver

Data source

Reference

Reference Type:

publication

Title:

Toxicity of n-C9 to n-C13 alkanes in the rat on short term inhalation

Author:

Nilsen, OG, Haugen, OA, Zaglsen, K et al.

Year:

1988

Bibliographic source:

Pharmacology and Toxicology 62, 259-266

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Principles of method if other than guideline:

Animals were exposed to vapour for 8-hr followed by a 14-d post-observation period.

GLP compliance:

not specified

Test type:

other: adaptation of standard method (8-hr exposure)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

n-nonane (n-C9)

IUPAC Name:

n-nonane (n-C9)

Constituent 2

Reference substance name:

n-decane (n-C10)

IUPAC Name:

n-decane (n-C10)

Constituent 3

Reference substance name:

n-undecane (n-C11)

IUPAC Name:

n-undecane (n-C11)

Constituent 4

Reference substance name:

n-dodcane (n-C12)

IUPAC Name:

n-dodcane (n-C12)

Constituent 5

Reference substance name:

n-tridecane (n-C13)

IUPAC Name:

n-tridecane (n-C13)

Details on test material:

All test samples had an analysed purity (GC) of 99.6-99.9%

Test animals

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 study initiation: 180-220 g
- Acclimation period: 4-6 d


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-23
- Humidity (%): 40-70
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

clean air

Details on inhalation exposure:

Exposure system: conical 0.7 m3 steel chambers with glass front door and walls; flow rate 30-40 l/min.
Vapour generation: test substance warmed (approx. 22 degrees C) under negative pressure and mixed with clean air to achieve required concentration
Analytical verification of achieved concentration: concentration in chamber air monitored automatically every 15 min using on-line GC-FID (Shimadzu GC-9A; 2 m x 1/8” column containing 10% SP-2100 on Supelcoport 100/120 mesh; helium carrier gas)
Standards: authentic standards processed in parallel
Aerosol: presence in chamber air quantified using a Royco 241 aerosol particle counter
Vapour:aerosol ratio: 3.04 x 10 e-6 for tridecane

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

8 h

Concentrations:

n-C9: 5280*, 4438, 3560 and 2414 ppm
n-C10: 1369* ppm
n-C11: 442* ppm
n-C12: 142* ppm
n-C13: 41* ppm

Values marked * were the maximum achievable vapour concentration in air

No. of animals per sex per dose:

10 males

Control animals:

no

Details on study design:

Animals were exposed to at least the saturated vapour concentration (20 degrees C) for each test substance for 8 hr followed by a full gross necropsy on day 14. The LC50 for n-nonane was calculated by probit analysis.

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LC50

Effect level:

4 467 ppm

Based on:

test mat.

Remarks:

n-nonane

Exp. duration:

8 h

Remarks on result:

other: No mortality for n-decane, n-undecane, n-dodecane or n-tridecane at maximum saturated vapour concentration in air

Effect levels 2

Sex:

male

Dose descriptor:

LC0

Effect level:

1 369 ppm

Based on:

test mat.

Remarks:

n-decane

Exp. duration:

8 h

Remarks on result:

other: no mortality at saturated vapour concentration

Effect levels 3

Sex:

male

Dose descriptor:

LC0

Effect level:

442 ppm

Based on:

test mat.

Remarks:

n-undecane

Exp. duration:

8 h

Remarks on result:

other: no mortality at saturated vapour concentration

Effect levels 4

Sex:

male

Dose descriptor:

LC0

Effect level:

142

Based on:

test mat.

Remarks:

n-dodecane

Exp. duration:

8 h

Remarks on result:

other: no mortality at saturated vapour concentration

Effect levels 5

Sex:

male

Dose descriptor:

LC0

Effect level:

41

Based on:

test mat.

Remarks:

n-tridecane

Exp. duration:

8 h

Remarks on result:

other: no mortality at saturated vapour concentration

Mortality:

n-nonane: 0/10, 1/10, 4/10, 9/10 at 2414, 3560, 4438 and 5280 ppm, respectively
n-decane, n-undecane, n-dodecane, n-tridecane: no mortality at maximum saturated vapour concentration

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute inhalation LC50 for n-nonane was 4467 ppm (23.4 mg/l) following 8-hr exposure.

Executive summary:

The acute inhalation toxicity of a series on C9-C13 n-alkanes was investigated in male SD rats following a single 8-hr exposure to vapour. A calculated LC50 of 4467 ppm (23.4 mg/l) was determined for n-nonane; the 4 -hr LC50 value is likely to exceed this value. No mortality was recorded for the other test substances after exposure to the maximum achievable vapour concentration in air. Maximum saturated vapour concentration decreased in a predictable manner with increasing C-number.