Reaction product of 9-Octadecenoic acid, (Z)-, sulfonated, potassium salts, hydrogen peroxide and sulfuric acid

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-06-18 to 2012-11-12

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

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 (UK) Limited, Margate, UK
- Age at study initiation: 5 - 6 weeks
- Weight at study initiation: 150 - 198 (males); 126 - 165 g (females)
- Fasting period before study:
- Housing: 2 to 3 per cage by sex in polycarbonate cages
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 23 °C
- Humidity (%): 48 - 78 %
- Air changes (per hr): 10 air changes per hour (minimum)
- Photoperiod (hrs dark / hrs light): 12 hours dark / 12 hours light

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Test material dosing formulations were prepared daily by dilution of PSOA in deionised water. Dosing formulations were stored at 4 °C until use.

The dose volume (10 mL/kg) was based on the most recent body weight measurement.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Duplicate top, middle and bottom samples for each sampling time point were collected for analysis by UV-spectrometry. Samples were stored at 4 °C until analysis.

Duration of treatment / exposure:

28 days

Frequency of treatment:

Daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 5, 15, 50 mg/kg/day (nominal)
Basis:
actual ingested

No. of animals per sex per dose:

5 males and 5 females (main study) and an additional 5 males and 5 females dosed at 0 and 50 mg/kg/day (recovery group)

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: dose levels were selected after examination of previous studies conducted with PSOA. In addition, the dose selection took into account experience with other corrosive peroxides for which repeated dose toxicity data are available.

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily
- Cage side observations included checks for mortality/moribundity

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: twice pretrial then daily throughout treatment period and twice weekly during recovery period

FOOD CONSUMPTION: Yes
- Time schedule: twice weekly

WATER CONSUMPTION: Yes
- Time schedule for examinations: visual inspection of water bottles performed regularly throughout the study

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: during week 4 (main study) and during week 6 (recovery group)
- How many animals: all animals

HAEMATOLOGY: Yes
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: No
- How many animals: all animals
- Time schedule for examinations: during week 4 (main study) and during week 6 (recovery group)

CLINICAL CHEMISTRY: Yes
- Animals fasted: No
- How many animals: all animals
- Time schedule for examinations: during week 4 (main study) and during week 6 (recovery group)

URINALYSIS: Yes
- Metabolism cages used for collection of urine: Yes (4 hours)
- Animals fasted: No
- How many animals: all animals
- Time schedule for examinations: during week 4 (main study) and during week 6 (recovery group)

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: during week 4 (main study) and during week 6 (recovery group)
- How many animals: all animals

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (all animals)
- Examination included evaluation of the carcass and musculoskeletal system, all external surfaces and orifices, cranial cavity and their associated organs and tissues.
- Selected organs were weighed together with terminal bodyweights.

HISTOPATHOLOGY: Yes
- Tissues were collected and preserved before being embedded in paraffin, sectioned, mounted on glass slides and stained with haematoxylin and eosin.
- Full tissues were examined for animals in the main study groups dosed at 0 and 50 mg/kg/day and gross lesions were examined for main study group animals dosed test material at 5 and 15 mg/kg/day

Statistics:

All statistical tests were two-sided and performed at the 5% significance level. Males and females were analysed separately. Data were analysed for homogeneity of variance using the F-Max test. If the group variances appeared homogeneous, a parametric ANOVA was used and pairwise comparisons were made using Fisher's F protected LSD method via Student's t-test. If the variances were heterogeneous, log or square root transformations were used. If the variances remained heterogeneous, then a Kruskal-Wallis nonparametric ANOVA was used and pairwise comparisons made using chi squared protection. In circumstances where it was not possible to perform the F Max test, the non-parametric ANOVA results were reported.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Description (incidence and severity):

there were no early deaths and no treatment-related clinical observations occurred during the study.

Mortality:

no mortality observed

Description (incidence):

there were no early deaths and no treatment-related clinical observations occurred during the study.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

No treatment-related changes in body weight occurred during the study.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

No changes in food consumption occurred during the study.

Food efficiency:

not examined

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

not specified

Ophthalmological findings:

no effects observed

Description (incidence and severity):

No treatment-related ophthalmic changes occurred during the study.

Haematological findings:

no effects observed

Description (incidence and severity):

No treatment-related haematology changes occurred during the study.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

No treatment-related clinical chemistry changes occurred during the study.

Urinalysis findings:

effects observed, treatment-related

Description (incidence and severity):

See "Details on results"

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

No treatment-related changes in neurobehaviour occurred during the study.

Organ weight findings including organ / body weight ratios:

no effects observed

Description (incidence and severity):

No treatment-related organ weight changes occurred during the study.

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

See "Details on results"

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

not specified

Details on results:

URINALYSIS
Urine volume in males and females dosed at 15 and 50 mg/kg/day was lower than in controls and this change was statistically significant for females. There was no corresponding change in the specific gravity and this change was no longer evident at the end of the recovery period. No other treatment-related urinalysis changes occurred during the study.

GROSS PATHOLOGY - Main Study Animals
Dark foci in the lung were seen at a higher incidence in males rats receiving test material at a dose of 50 mg/kg/day than in their contemporary controls. Other gross findings observed were considered incidental, of the nature commonly observed in this strain and age of rat, and/or were of similar incidences in control and treated animals and, therefore, were considered unrelated to administration of test material.

GROSS PATHOLOGY - Recovery Group Animals
No significant difference in the incidence of dark foci in the lung was seen between treated and control animals. There was a higher incidence of discolouration or "speckling" of the thymus in treated animals compared with their controls. Other gross findings were considered incidental, of the nature commonly observed in this strain and age of rat, and/or were of similar incidences in control and treated animals and, therefore, were considered unrelated to administration of test material.

HISTOPATHOLOGY: Main Study Animals
There were no microscopic findings which were associated with the administration of test material. No target tissues were identified. Alveolar hemmorrhage, which provided the microscopic correlate for the dark foci seen grossly in the lung, was seen at a similar incidence in both control and treated rats. Other microscopic findings were considered incidental, of the nature commonly observed in this strain and age of rat, and/or were of similar incidences in control and treated animals and, therefore, were considered unrelated to administration of test material.

HISTOPATHOLOGY: Recovery Group Animals
Multifocal hemorrhage provided the microscopic correlate for the gross finding of discolouration or "speckling" observed in the thymus; the extent of hemorrhage was minimal and this is generally considered to be a common background finding. Other microscopic findings were considered incidental, of the nature commonly observed in this strain and age of rat, and/or were of similar incidences in control and treated animals and, therefore, were considered unrelated to administration of test material.

Effect levels

Dose descriptor:

NOEL

Effect level:

50 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects noted at this dose level.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Under the conditions of the study, the NOEL of the test material was determined to be 50 mg/kg/day.

Executive summary:

The repeat dose toxicity of the test material was determined in accordance with the standardised guideline OECD 407. During the study groups of rats were dosed test material orally, by gavage, for 28 consecutive days. Groups of recovery animals were included to evaluate the potential reversibility of any findings over a 14 day recovery period. Test material was dosed at 0, 5, 15 and 50 mg/kg/day. Clinical signs, body weight changes, food consumption, opthalmology, detailed functional observations, clinical pathology parameters, gross necropsy findings, organ weights and histopathologic examinations were performed.

Under the conditions of the study, no treatment-related findings were noted in any of the parameters assessed. The mucous membranes of the oesophagus and stomach tolerated the test material up to a concentration of 5 mg/mL without any adverse effects. With regard to the local mucous membrane compatibility, a no observed adverse effect level of 5 mg/mL (50 mg/kg/day) can be derived.

In conclusion, administration of the test material by once daily oral gavage for 28 days was well tolerated in rats at levels of 5, 15 and 50 mg/kg/day. Based on these results, the no-observed effect level was considered to be 50 mg/kg/day.