[No public or meaningful name is available]

Endpoint summary

Description of key information

The results of three studies of skin irritation in vivo performed on tetradecanoic acid were considered to determine the skin irritation potential of the test item. Since the test item is a reaction mass of tetradecanoic anhydride and tetradecanoic acid, tetradecanoic acid was used for the read-across.

The classification of the test item regarding the skin irritation is based on the study with the strictest result, which classifies tetradecanoic acid as "highly irritating". Here the total irritation score for all subjects for all 21 applications of the formulation containing 5% of myristic acid was 609 of a maximal possible score of 756. The substance was therefore classified as Category 2 (irritant) based on GHS criteria.

The classification of the test item regarding the eye irritation is based on an in-vivo study performed on tetradecanoic acid, where lotion formulations containing 1.5% of myristic acid resulted minimally irritating to rinsed and unrinsed treated eyes of rabbits. The test item was classified as Category 2 (irritating to eyes) based on GHS criteria.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

June 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Guideline:

other: information not available

GLP compliance:

not specified

Remarks:

information not available

Specific details on test material used for the study:

Commercial grade myristic acid

Species:

other: human

Type of coverage:

occlusive

Number of animals:

20

Details on study design:

SIOPT (single insult occlusive patch test)

Irritation parameter:

other: primary irritation index

Score:

0.2

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

Commercial grade myristic acid produced no irritation in 17, mild erythema in 2, and moderate erythema in 1 of 20 panelists.

Interpretation of results:

GHS criteria not met

Conclusions:

The primary irritation index was 0.2, and myristic acid was considered "practically non irritating."

Reference 2

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

June 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Guideline:

other: information not available

GLP compliance:

not specified

Remarks:

information not available

Specific details on test material used for the study:

Several bar soap formulations with concentrations of Myristic Acid of 10, 22.1, and 91%

Species:

other: human

Type of coverage:

occlusive

Amount / concentration applied:

0.2 mL volume of an 8% aqueous preparation

Duration of treatment / exposure:

once daily for 5 days

Observation period:

5 days

Number of animals:

16

Details on study design:

Preparation was applied to the ventral skin of the forearm under occlusive patches using the Frosch-Kligman soap chamber test

Irritation parameter:

erythema score

Remarks:

formulation with 10% myristic acid

Score:

> 0 - < 5

Max. score:

1.41

Remarks on result:

positive indication of irritation

Remarks:

slightly irritating

Irritation parameter:

erythema score

Remarks:

formulation with 22.1 % myristic acid

Score:

> 0 - < 5

Max. score:

1.73

Remarks on result:

positive indication of irritation

Remarks:

moderately irritating

Irritation parameter:

erythema score

Remarks:

formulation with 91% myristic acid

Score:

> 0 - < 5

Max. score:

1.95

Remarks on result:

positive indication of irritation

Remarks:

moderately irritating

Interpretation of results:

study cannot be used for classification

Conclusions:

The formulations were considered "slightly" to "moderately irritating" and erythema scores were 1.41, 1.73, and 1.95 on a scale of 0 to 5 for the formulations containing 10, 22.1, and 91% myristic acid, respectively.

Reference 3

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Guideline:

other: information not available

GLP compliance:

not specified

Remarks:

information not available

Specific details on test material used for the study:

white cleanser lotion formulation containing 5% myristic acid

Species:

other: human

Type of coverage:

other: closed-patch

Amount / concentration applied:

formulation containing 5% myristic acid

Duration of treatment / exposure:

21 days

Number of animals:

12

Irritation parameter:

overall irritation score

Basis:

other: all subjects

Score:

609

Max. score:

756

Remarks on result:

positive indication of irritation

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

The total irritation score for all subjects for all 21 applications of the formulation was 609 of a maximal possible score of 756. The formulation was considered "highly irritating".

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

June 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Guideline:

other: information not available

GLP compliance:

not specified

Remarks:

information not available

Specific details on test material used for the study:

Commercial grade myristic acid and 50% myristic acid in petrolatum.

Species:

rabbit

Strain:

not specified

Details on test animals or tissues and environmental conditions:

Albino rabbits

Vehicle:

not specified

Amount / concentration applied:

commercial grade myristic acid and 50% myristic acid in petrolatum

Duration of treatment / exposure:

1 day

Observation period (in vivo):

1 day

Details on study design:

Lotion formulations containing 1.5% myristic acid were applied to rinsed (20 mL ionized water at room temperature, 30 seconds after instillation) and unrinsed treated eyes of rabbits.

Irritation parameter:

other: not specified

Basis:

other: not specified

Time point:

24 h

Remarks on result:

probability of mild irritation

Remarks:

Formulations were minimally irritating to rinsed and unrinsed treated eyes of rabbits

Interpretation of results:

Category 2 (irritating to eyes) based on GHS criteria

Conclusions:

Lotion formulations containing 1.5% myristic acid were minimally irritating to rinsed (20 mL ionized water at room temperature, 30 seconds after instillation) and unrinsed treated eyes of rabbits.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)