(R)-p-mentha-1,8-diene

Direct observations: clinical cases, poisoning incidents and other

Administrative data

Endpoint:

direct observations: clinical cases, poisoning incidents and other

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

1998

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1998

Materials and methods

Study type:

study with volunteers

Endpoint addressed:

acute toxicity: inhalation

Principles of method if other than guideline:

Odor and nasal pungency thresholds were determined in normosmics (2 females and 1 male) and anosmics (2 females and 2 males), respectively exposed to R-(+)-limonene at concentrations of 3.7, 11, 33 and 100%.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

(R)-p-mentha-1,8-diene

EC Number:

227-813-5

EC Name:

(R)-p-mentha-1,8-diene

Cas Number:

5989-27-5

Molecular formula:

C10H16

IUPAC Name:

4-isopropenyl-1-methylcyclohexene

Test material form:

liquid

Method

Subjects:

- Number of subjects exposed: Seven
- Sex: 4 females, 3 males
- Age: Anosmic group: females: 39-42 years, male: 59 years; Normosmic group: females: 25-37 years, males: 31-58 years
- Known diseases: 3/7 subjects were congenital anosmics i.e. lacking olfaction

Route of exposure:

inhalation

Reason of exposure:

intentional

Exposure assessment:

measured

Results and discussion

Clinical signs:

- Odor threshold for R-(+)-limonene in normosmics was determined to be approximately 10 ppm.
- Nasal pungency was not evoked in the anosmics.

Any other information on results incl. tables

None

Applicant's summary and conclusion

Conclusions:

Odor threshold for R-(+)-limonene in normosmics was determined to be approximately 10 ppm. Nasal pungency was not evoked in the anosmics.

Executive summary:

In an inhalation study, groups of normosmics (2 females and 1 male) and anosmics (2 females and 2 males) were exposed to R-(+)-limonene at concentrations of 3.7, 11, 33 and 100%. Stimuli were presented via 270-mL polypropylene squeeze-bottles containing 30 mL of solution. Odor and nasal pungency thresholds were measured in normosmics and anosmics, respectively via a two-alternative forced-choice procedure with presentation of progressively higher concentrations. Starting from the lowest concentration, each trial entailed the presentation of a blank (mineral oil) and a stimulus. The subject’s task was to choose the stronger stimulus. If the participant was correct, the same concentration was presented next, paired with a blank. If the participant was incorrect, the next higher concentration was presented next, also paired with a blank. The first concentration chosen correctly five times in a row was taken as the threshold. Each type of threshold was measured eight times per subject–stimulus combination. Odor threshold for R-(+)-limonene in normosmics was determined to be approximately 10 ppm. Nasal pungency was not evoked in the anosmics.