Hexadecyl 3,5-bis-tert-butyl-4-hydroxybenzoate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 - 29 June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nohsan, Notification No 8147, April 2011, including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

CYASORB® UV-2908 Light Stabilizer

IUPAC Name:

CYASORB® UV-2908 Light Stabilizer

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): CYASORB® UV-2908 Light Stabilizer
- Substance type: White to off-white powder
- Physical state: Powder
- Purity: >98%
- Lot/batch No.: WP1022803
- Expiration date of the lot/batch: 18 April 2013
- Storage condition of test material: At room temperature protected from light
- Hygroscopic: No
- Volatile: No
- Reactivity: Reactive to oxygen, moisture and light
- Test substance handling: For oxygen and moisture: no specific handling required
- For light: use amber-coloured glassware or wrap container in aluminium foil
- pH (1% in water, indicative range): 7.2 – 6.7

Test animals

Species:

rat

Strain:

other: Wistar strain, Crl:WI (Han)

Sex:

female

Details on test animals or test system and environmental conditions:

- Source: Charles River Deutschland, Kisslegg, Germany
- Age at study initiation: Young adult animals (approx. 8-9 weeks old)
- Weight at study initiation: Body weight variation was within +/- 20% of the sex mean (first group: 160 - 173 grams; second group: 154 - 169 grams).
- Fasting period before study: Animals were deprived of food overnight prior to dosing and until 3-4 hours after administration of the test substance. Water was available ad libitum.
- Housing: Group housing of 3 animals per cage in labeled Macrolon cages
- Diet: Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany).
- Water: Free access to tap water.
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
Environmental controls for the animal room were set to maintain 18 to 24°C, a relative humidity of 40 to 70%, approximately 15 room air changes/hour, and a 12-hour light/12-hour dark cycle.

IN-LIFE DATES: From: 12 - 29 June 2012

Administration / exposure

Route of administration:

oral: gavage

Details on oral exposure:

GAVAGE METHOD: plastic feeding tubes.

Frequency: single dosage, on Day 1.

MAXIMUM DOSE VOLUME APPLIED: 2000 mg/kg (10 mL/kg) body weight.
Dose volume calculated as dose level (g/kg) / specific gravity.

DOSAGE PREPARATION: The formulations (w/w) were prepared within 2 hours prior to dosing. Homogeneity was accomplished to a visually acceptable level. Adjustment was made for specific gravity of the vehicle. No correction was made for purity of the test substance.

No. of animals per sex per dose:

6 (2 groups of three females in a stepwise manner)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:
Mortality/Viability: Twice daily.
Body weights: Days 1 (pre-administration), 8 and 15
Clinical signs: At periodic intervals on the day of dosing (Day 1) and once daily thereafter, until Day 15.
- Necropsy of survivors performed: At the end of the observation period, all animals were sacrificed by oxygen/carbon dioxide procedure and subjected to necropsy. Descriptions of all internal macroscopic abnormalities were recorded.
- Other examinations performed: none.

Statistics:

No statistical analysis was performed (The method used is not intended to allow the calculation of a precise LD50 value).

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred

Clinical signs:

other: Hunched posture was noted in all animals on Day 1.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In an acute oral toxicity study with female rats, performed according to OECD/EC test guidelines, an LD50 >2000 mg/kg bw was determined.

According to the OECD 423 test guideline, the LD50 cut-off value was considered to exceed 5000 mg/kg body weight.

Based on these results, CYASORB® UV-2908 Light Stabilizer does not have to be classified and has no obligatory labelling requirement for acute oral toxicity according to the:
- Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2011),
- Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures.