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Toxicological information

Repeated dose toxicity: dermal

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Administrative data

Endpoint:
short-term repeated dose toxicity: dermal
Data waiving:
other justification
Justification for data waiving:
other:
Cross-referenceopen allclose all
Reason / purpose for cross-reference:
data waiving: supporting information
Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
up to 2008
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Source is a published handbook, no data on GLP/guideline compliance/method. Acceptable with restriction as handbook is peer reviewed and considered a reliable source.
Principles of method if other than guideline:
The use of secondary sources of data is acceptable when they are based on a critical evaluation of peer-reviewed data and a consequent selection of a reliable and representative value for the property under investigation. The introduction to the CRC Handbook of Chemistry and Physics states that data for physical constants have been taken from many sources, including both compilations and the primary literature. Where conflicts were found, the value deemed most reliable was chosen. Therefore, although the method used is not known, the values presented here are acceptable as they are from a reliable secondary source of phys chem. data.
GLP compliance:
not specified
Remarks:
Not reported
Type of method:
other: No method was reported
Partition coefficient type:
octanol-water
Analytical method:
not specified
Type:
log Pow
Partition coefficient:
3.45
Temp.:
25 °C
pH:
7
Remarks on result:
other: pH not stated, therefore assumed standard
Details on results:
No further details reported
Conclusions:
The Log Kow of n-pentane is 3.45
Executive summary:

There is no available information on the methods used to determine the value for this endpoint. However, this information is taken from the CRC Handbook which is considered to be a reliable peer reviewed handbook and suitable for use as the key study for this endpoint. Therefore the Log Kow of n-pentane is 3.45.

Reason / purpose for cross-reference:
data waiving: supporting information
Reference
Endpoint:
water solubility
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Up to 1966
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Predates implementation of GLP and development of standard guidelines but otherwise acceptable for assessment
Principles of method if other than guideline:
n-Pentane at one atmosphere was added to a glass equilibraton bottle filled with distilled water by displacing water until the volume of the aqueous phase was 3/4 of the volume of the bottle. The gas was maintained over the water. A rubber balloon in the line from the gas cylinder to the bottle served as a resevoir and was remained in-line until the aqueous phase was sampled. The 3/4 full bottle was shaken for 5 to 10 minutes and then allowed to stand at least 30 minutes prior to analysis. Aqueous samples were taken using a Hamilton syringe and transferred to the gas chromatograph (GC).

Analysis was by gas chromatograph (GC) with a hydrogen-flame ionization detecter (Beckman). The chromatographic column was 12 ft. x 0.25 in., stainless steel tubing packed with 25% SE 30 gum rubber on 30-60 mesh firebrick. Helium flow through the column was 65cc/min.

Aqueous samples were taken from the equilibration bottle through a septum in tubing at the base of the bottle using a Hamilton syringe and transferred to the GC. Aqueous phase concentrations of propylene were determined against a standard curve prepared from the gas sample used in the aqueous equilibration procedure
GLP compliance:
no
Remarks:
No data reported
Type of method:
other: Non-standard method
Water solubility:
38.5 mg/L
Temp.:
20 °C
pH:
7
Remarks on result:
other: pH not stated, therefore assumed standard
Details on results:
No further details provided
Conclusions:
Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
This study is well documented and meets basic scientific principles. It is unclear what effect the impurities might have had on the result and how the authors accounted for them in determining the solubility value. For this reason the study has been classified as reliable with restrictions. Solubility of n-pentane was reported as 38.5 mg/l at 20°C
Executive summary:

This study measured the solubilities of 65 hydrocarbons in water, at room temperature, by the direct injection of hydrocarbon-saturated water into a gas chromatograph. The concentration of hydrocarbon was determined by measuring the area under the chromatogram peak. The solubility of n-pentane was determined to be 38.5 mg/l at 20°C.

Data source

Materials and methods

Results and discussion

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion