Icosan-1-ol

Repeated dose toxicity: dermal

Administrative data

Endpoint:

chronic toxicity: dermal

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

15 March to 15 June 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 411 (Subchronic Dermal Toxicity: 90-Day Study)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Fatty Alcohol Blend

IUPAC Name:

Fatty Alcohol Blend

Test material form:

other: liquid

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 Inc., USA
- Age at study initiation: males approximately 43 days and females approximately 64 days
- Weight at study initiation: 225 - 299g males; 214 - 246g females
- Fasting period before study: no
- Housing: individually in wire mesh cages
- Diet (ad libitum): Purina Certified Rodent Chow #5002
- Water (ad libitum): municpal water supplied to Test Facility
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°F): 71.3 - 75.2
- Humidity (%): 41.6 - 77.7
- Air changes (per hr): not stated
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 15 March 1994 To: 15 June 1994

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

other: 0.9% Sodium chloride (this was dosed to the control group at a dose volume of 1.2 ml/kg.

Details on exposure:

TEST SITE
- Area of exposure: dorsal skin

- Type of wrap: gauze binder, secured with tape

REMOVAL OF TEST SUBSTANCE
- Washing: test article was removed from the application site with a wet paper towel

- Time after start of exposure: six hours

TEST MATERIAL - Control group
- Amount(s) applied: 1.2 ml/kg (Control and high dose), 0.12 ml/kg (low dose), 0.36 ml/kg (intermediate dose)

- Concentration (if solution): 0.9% saline

- Constant volume or concentration used: yes

TEST MATERIAL - Test groups(2-4)
- Amount applied: 100, 300 and 1000 mg/kg/day respectively

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

The application sites were wrapped for six hours with a gauze binder, secured with tape.

The range of areas exposed averaged approximately 8, 2, 4 or 9% of total body surface area for the Control, 100, 300 or 1000 mg/kg/day groups respectively.

Frequency of treatment:

Application for five days a week over thirteen consecutive weeks to the shaved intact dorsal skin of each rat for a minimum of 65 applications.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

100 mg/kg bw/day

Doses / concentrations 2

Dose / conc.:

300 mg/kg bw/day

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day

No. of animals per sex per dose:

Control group: 20 rats (10 male and 10 female) which received 0.9% saline on a comparable regimen at a dose volume of 1.2 ml/kg.

Three test groups: 20 rats (10 males and 10 females) administered dosage levels of 100, 300 and 1000 mg/kg/day respectively.

Control animals:

yes

Details on study design:

- Dose selection rationale: not stated

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once weekly

DERMAL IRRITATION: Yes
- Time schedule for examinations: once weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/animal/day: Yes
- Time schedule for examinations: weekly

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: prior to start of dosing and Week 12
- Dose groups that were examined: all

HAEMATOLOGY: Yes
- Time schedule for collection of blood: Week 13 at scheduled necropsy
- Anaesthetic used for blood collection: not stated
- Animals fasted: Yes
- How many animals: all
- Parameters checked in table No.1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Week 13 at scheduled necropsy
- Animals fasted: Yes
- How many animals: all
- Parameters checked in table No.2 were examined.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

ORGAN WEIGHTS: Yes (see table 3)
GROSS PATHOLOGY: Yes (see table 4)
HISTOPATHOLOGY: Yes (see table 4)

Other examinations:

Selected organs were weighed and a microscopic examination was conducted on selected tissues from all animals at the scheduled necropsy.

Statistics:

All analyses were conducted using two-tailed tests for significance levels of 5% and 1% comapring the treated groups to the vehicle control group by sex. Body weight, body weight change, food consumption, clinical laboratory and absolute and relative organ weight data were subjected to a one-way analysis of variance follwoed by Dunnett's Test. Clinical laboratory values for cell types that occur at low incidence (i.e. monocytes, eosinophils, basophils and unsegmented neutrophils) were not subjected to statistical analysis.

Results and discussion

Results of examinations

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

Vocalisation, struggling during exposure and hypersensitivity to touch.

Dermal irritation:

effects observed, treatment-related

Description (incidence and severity):

Marked dermal irritation was noted in all dose groups and consisted of very slight to severe erythema, very slight to moderate edema, persistant desquamation, eschar, exfoliation, clear exudate and fissuring.

Mortality:

mortality observed, treatment-related

Description (incidence):

Vocalisation, struggling during exposure and hypersensitivity to touch.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

The mean body weights were lower in the middle and high dose groups compared to the control group.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Mean food consumption (evaluated as g/animal/day) was slightly but consistently decreased in the high dose group (males) during the first two thirds of the study period but was comparable with Controls thereafter.

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

no effects observed

Description (incidence and severity):

No test related ophthalmic lesions were present at the week 12 opthalmologic examinations.

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

Mean white blood cell counts were increased in a non dose related manner in all the test groups (not the control). This was attributed to the acute dermal inflammation that was observed.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

In the serum chemistry parameters albumin means were decreased and globulin means were increased (resulting in decreased A/G ratios). Again this was attributed to the acute dermal inflammation that was observed.

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

The adrenals, brain, kidneys, liver, ovaries and testes were weighed at necropsy. No remarkable statistically significant changes in organ weight were note for any of the organs, except increaed absolute and relative adrenal weights.

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

Scabbing and thickening of the skin was noted in all dose groups.

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Squamous cell hyperplasia, hyperkeratosis and suppurative inflammation were noted at teh application site in all treated groups.

Histopathological findings: neoplastic:

no effects observed

Description (incidence and severity):

No effect of treatment.

Details on results:

CLINICAL SIGNS AND MORTALITY
Vocalisation (due to pain) was the predominant sign observed in the high dose group (females) generally on one to three days most often during the second week of test article administration. Excessive struggling was also reported during exposure on single occasions for one male in the low dose group and two female in the high dose group. Hypersensitivity to touch was also reported on two separate occasions for a single high dose male.
                                                                                                          
Marked dermal irritation was noted in all dose groups and consisted of very slight to severe erythema, very slight to moderate edema, persistant desquamation, eschar, exfoliation, clear exudate and fissuring.

BODY WEIGHT AND WEIGHT GAIN
Group mean body weights were lower than Control during the study for males at 300 mg/kg/day and both sexes at 1000 mg/kg/day by up to 19% at the end of the treatment period. A simialr, but less marked effect on body weight was recorded for both sexes at 100 mg/kg/day and 300 mg/kg/day females with group mean body weight up to 6% lower than Control at the end of the treatment period.

FOOD CONSUMPTION
Group mean food consumption was slightly lower than Control for males at 1000 mg/kg/day up to Week 9 of the treatment period. Slightly lower group mean food consumption was also noted for females at the same dose during the first week of treatment. For both males and females food consumption was comparable to Controls thereafter.

OPHTHALMOSCOPIC EXAMINATION
No effect of treatment.

HAEMATOLOGY
Group mean white blood cell count and neutrophil counts were increased in treated groups compared to Control. The magnitude of the increases was not dose-related. The effect on white cell counts was considered to be attributable to the acute dermal inflammatory response.

CLINICAL CHEMISTRY
Group mean albumin was increased and group mean globulin and A/G ratio were decreased in a non dose-related manner in all treatment groups. These changes were considered to be indicative of the acute dermal inflammatory response.

A dose-related decrease in group mean glucose levels was noted in all treated groups. Group mean calcium was decreased in 1000 mg/kg/day males and females. Increases in group mean urea nitrogen, alkaline phosphatase, aspartate aminotransferse and/or alanine aminotransferase were also noted at 1000 mg/kg/day.

ORGAN WEIGHTS
Group mean absolute and relative adrenal weights were increased in all treated groups.

GROSS PATHOLOGY
The only test article related gross lesions observed included scabbing and thickening of the skin at the test site. (Irritant related effects). There were no other test article related gross findings at the scheduled necropsy.

HISTOPATHOLOGY: NON-NEOPLASTIC
Squamous cell hyperplasia, hyperkeratosis and suppurative inflammation in the skin of the application site was noted in males and females of all treated groups.

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: NOAEL for systemic effects

2

Dose descriptor:

LOAEL

Effect level:

100 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: NOAEL for local effects, based on severe dermal irritation recorded at all doses.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Based on the data that was reported the No-Observed-Effect-Level (NOEL) following dermal administration of fatty alcohol blend for a minimum of 90 days was stated to be less than 100 mg/kg/day. This is based primarily on the local irritation (and related) effects.

The local irritation effects are considered adverse and therefore the local, dermal Lowest-Observed-Adverse-Effect-Level (LOAEL) is 100 mg/kg/day (2.8 mg/cm3 based on test substance applied to 2% body surface area at this dose). It should be noted that the test substance was repeatedly applied to already damaged skin, which may have exacerbated the effects noted. Furthermore the dermal effects noted were variable in terms of the relationship of severity with duration of administration. The clinical signs and effects on body weight and food consumption are considered to be a consequence of the local irritant effect and the effects on white blood cell counts and albumin and globulin levels attributable to the acute dermal inflammatory response. The increased adrenal weights (with no associated pathological changes) were attributed to a stress response, also as a result of the dermal irritation. Therefore these effects are secondary to the local irritant effect of fatty alcohol blend.

There were also changes to some clinical chemistry parameters noted (decreased glucose and calcium, increased urea nitrogen, alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase). The magnitude of change was generally not marked and/or was without pathological correlate in all cases and so they were considered not be adverse. Therefore, as there were no systemic effects noted that could not be attributed to the local irritant response, or were considered to be adverse, the systemic No-Observed-Adverse-Effect-Level following dermal administration of fatty alcohol blend for a minimum of 90 days was considered to be 1000 mg/kg/day (the highest dose tested).

Executive summary:

Intermediate (>C8 to C12) and higher (>C12) linear LCAAs are non-irritant at the site of first contact and are without a neurotoxic potential.