Icos-1-ene

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

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

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study is classified as reliable without restriction because it was conducted according to OECD Guideline 402 and GLPs.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes (incl. QA statement)

Remarks:

UK

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Alkenes, C20-24

IUPAC Name:

Alkenes, C20-24

Details on test material:

This substance is very similar in structure to the substance being registered.

- Name of test material (as cited in study report): C20-24 alkenes, branched and linear
- Substance type: Alkenes, C20-24
- Physical state: Liquid
- Analytical purity: Not reported
- Lot/batch No.: C1829-50A
- Storage condition of test material: Room temperature

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Ltd., Kent, UK
- Age at study initiation: 8 to 12 weeks old
- Weight at study initiation: 206 grams to 225 grams
- Fasting period before study: Not reported
- Housing: Individual
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 to 22°C
- Humidity (%): 44 to 62%
- Air changes (per hr): 15 per hr
- Photoperiod (hrs dark / hrs light): 12 hrs dark / 12 hrs light

IN-LIFE DATES: From: 11 November 1997 To: 25 November 1997

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: 35 cm2
- % coverage: Not reported
- Type of wrap if used: Elastic wrap

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Liquid paraffin BP
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount applied (weight with unit): 2000 mg/kg (2.52 mL/kg)
- Concentration (if solution): Undiluted (100%)
- Constant volume or concentration used: Yes

Duration of exposure:

24 hours

Doses:

2000 mg/kg

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: Daily
- Necropsy of survivors performed: Yes
- Other examinations performed: Clinical signs, body weight, gross pathology, irritation

Statistics:

None performed

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Based on lack of mortality or any other systemic signs of toxicity

Mortality:

There were no deaths.

Clinical signs:

other: There were no signs of systemic toxicity noted.

Gross pathology:

There were no abnormalities noted during gross pathology.

Other findings:

None reported

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Not classified because LD50 is greater than the requirements for a Category 4 toxicant (2000 mg/kg) Criteria used for interpretation of results: EU

Conclusions:

The LD50 for alkenes C20-24, branched and linear was found to be > 2000 mg/kg bw. Alkenes C20-24, branched and linear, are not classified according to EU classification.

Executive summary:

Justification for Read Across

Several criteria justify the use of the read across approach to fill data gaps for linear alpha olefins using isomerised olefins; alpha, internal, linear and branched – multiple carbon number analogues. Studies indicate that changing the carbon number, the location of the double bond, or adding branching does not measurably alter the effects on mammalian health endpoints. There is a consistent toxicity potency pattern for isomerised olefins with a range of carbon numbers and they are considered to have minimal acute toxicity potential. Genotoxicity studies indicate that these materials are not mutagenic. No adverse systemic toxicity was observed in a 90-day repeated oral dose study in which rats were exposed to alkenes, C20-24. The toxicological profile of multiple carbon number isomerised olefins described above indicates a low hazard potential for human health. There do not appear to be any significant toxicological differences between multiple carbon number isomerised olefins and linear alpha olefins. Therefore, read across between these two categories can be justified.

In an acute dermal toxicity study, groups of young adult Sprague-Dawley rats (5/sex) were dermally exposed to alkenes C20-24, branched and linear, undiluted for 24 hours to 35 cm²body surface at a limit dose of 2000 mg/kg bw. Animals were then observed for 14 days.

 

There were no treatment related clinical signs, necropsy findings or changes in body weight. The dermal LD50 was determined to be > 2000 mg/kg in males and females.

 

This study received a Klimisch score of 1 and is classified as reliable without restriction because it was conducted according to OECD Guideline 402 and GLPs.