D-cellobiose

Endpoint summary

Description of key information

A 90-day repeated dose drinking water study in rats is available, in which no adverse effects were observed up to 6852 mg Cellobiose per kg body weight. From this study, it can be concluded that an acute oral toxicity study with a single dose of max. 5000 mg Cellobiose per kg body weight will also not induce any adverse effects.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Remarks:

A 90-day repeated dose drinking water study in rats is available, in which no adverse effects were observed up to 6852 mg Cellobiose per kg body weight. The results of the study are used to assess the acute oral toxicity study.

Adequacy of study:

key study

Study period:

October 25, 2016, to October 13, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Remarks:

A 90-day repeated dose drinking water study in rats is available, in which no adverse effects were observed up to 6852 mg Cellobiose per kg body weight. The results of the study are used to assess the acute oral toxicity.

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Version / remarks:

version of September 21, 1998

Deviations:

no

GLP compliance:

yes

Test type:

other: 90-day drinking water study

Limit test:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source (i.e. manufacturer or supplier) and lot/batch number of test material: Pfeifer & Langen GmbH
& Co. KG, Batch no. CB 20.05.2016
- Purity, including information on contaminants, isomers, etc.: purity > 99%
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL - Storage condition of test material: room temperature

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories Germany GmbH, Sandhofer Weg 7, 97633 Sulzfeld, Germany
- Age at study initiation: males: 51 days; females: 61 days
- Weight at study initiation: Males: 241.0 g - 285.5 g; Females: 206.8 g - 246.4 g
- Fasting period before study: no reported
- Housing: The animals were kept singly in MAKROLON cages (type III plus) with a basal surface of a pprox. 39 cm x 23 cm and a height of approx. 18 cm.
- Diet (e.g. ad libitum): ssniff-R/M-H V1534 (ssniff Spezialdiäten GmbH, 59494 Soest, Germany) ad
libitum
- Water (e.g. ad libitum): ad libitum - Acclimation period: no reported
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C ± 3°C
- Humidity (%): 55% ± 15%
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: drinking water

Vehicle:

water

Details on oral exposure:

The oral route is the default route. In addition, the study was conducted for an application for aut horisation of a novel food in accordance with Article 10 of Regulation (EU) 2015/2283

Doses:

25, 50 and 100 mg/L drinking water

No. of animals per sex per dose:

10 animals/sex/dose

Control animals:

yes

Details on study design:

Observations and examinations performed and frequency

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: at least once daily
- Cage side observations: Any signs of illness or reaction to treatment were recorded for each
individual animal. Cage-side observations included skin/fur, eyes, mucous membranes, respiratory and circulatory systems, somatomotor activity, and behaviour patterns. The onset, intensity and duration of any signs observed were recorded.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: before first exposure and then once per week
- Observations: changes in skin, fur, eyes, mucous membranes, occurrence of secretions and
excretions and autonomic activity (e.g. lacrimation, pilo-erection, pupil size, unusual respiratory pattern). Changes in gait, posture and response to handling as well as the presence of clonic or tonic movements, stereotypies (e.g. excessive grooming, repetitive circling) or bizarre behaviour (e.g. self-
mutilation, walking backwards) were also recorded.

BODY WEIGHT: Yes
- Time schedule for examinations: The weight of each rat was recorded at the time of group all ocation, daily from the day of commencement of treatment up to and including test week 6 for dose ad justment, and thereafter weekly throughout the experimental period.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted
averages from the consumption and body weight gain data: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes - Time schedule for examinations: daily

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: Examinations were performed on all animals before first dosing, at
the end of the main study (test week 13) and at the end of the recovery period (test week 17) - Dose groups that were examined:all

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the end of the treatment period and at the end of the reco very period
- Anaesthetic used for blood collection: light ether anaesthesia
- Animals fasted: Yes (overnight)
- How many animals: all
- Parameters checked in table 1 were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at the end of the treatment period and at the end of the recov ery period
- Animals fasted: Yes (overnight)
- How many animals:all
- Parameters checked in table 2 were examined.

PLASMA/SERUM HORMONES/LIPIDS: No

URINALYSIS: Yes
- Time schedule for collection of urine: at the end of the treatment period and at the end of the recove ry period
- Metabolism cages used for collection of urine: Not specified
- Animals fasted: Yes
- Parameters examined: volime, pH, specific gravity, Protein, Glucose, Bilirubin, Urobilinogen,
Ketones, Haemoglobin (HGB) (approx. values), Nitrite, microscopic examinations (Epithelial cells, Leucocytes, Erythrocytes, Organisms, further constituents (i.e. sperm, casts), Crystalluria)

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: test weeks 13 and 17 (before any blood sampling for laboratory
examinations)
- Dose groups that were examined:all
- Battery of functions tested: sensory activity / grip strength / motor activity (for details see Table 3
below)

IMMUNOLOGY: No

Statistics:

Data for toxicology and pathology were captured, as far as possible; using the departmental computer ized systems (Provantis® Integrated preclinical software, version 9.4.0, Instem LSS Ltd., Stone, Sta ffordshire ST15 0SD, United Kingdom). Raw data not fully compatible with the computerized systems
were maintained on paper according to appropriate SOPs.
The test item groups 2 to 4 were compared to the control group 1. The following statistical methods
were used:
- Multiple t-test based on DUNNETT, C. W.
- Exact test of R. A. FISHER (if applicable)
The following settings were used for the statistical evaluation of the parametricvalues captured by
Provantis:
Homogeneity of variances and normality of distribution were tested using the BARTLETT’s and
SHAPIRO-WILKS test. In case of heterogeneity and/or non- normality of distribution, stepwise tr ansformation of the values into logarithmic or rank values was performed prior to ANOVA. If the
ANOVA yielded a significant effect (p ≤ 0.05), intergroup comparisons with the control group was made by the DUNNETT’s test (p ≤ 0.01 and p ≤ 0.05).
The following statistical methods were used for the data not captured with the Provantis system, i.e. Numerical functional tests: Body temperature / Hind leg splay / Grip strength / Spontaneous motility): STUDENT's t-test

Key result

Sex:

male/female

Dose descriptor:

LD0

Effect level:

> 6 852 mg/kg bw

Based on:

test mat.

Remarks on result:

not determinable due to absence of adverse toxic effects

Remarks:

The effect level is the no observed effect level from a 90-day repeated dose drinking water study in rats.

Interpretation of results:

GHS criteria not met

Conclusions:

In a GLP-compliant 90-day repeated dose drinking water study in rats according to OECD TG 408, no adverse effects were observed up to 6852 mg Cellobiose per kg body weight. Based on this result, the acute oral toxicity will be higher than 6852 mg/kg bw.

Executive summary:

In a GLP-compliant study according to OECD TG 408 in rats, cellobiose administered via drinking water did not induce any adverse effects. The experimental no-observed-adverse-effect level (NOAEL) was equal to or greater than 10% Cellobiose in drinking water (equivalent to ~ 6852 and ~ 8043 mg Cellobiose per kg body weight for males and females, respectively). All observed effects, i.e., marginally reduced body weight and food consumption, are considered to be secondary to a reduced drinking water intake at the highest dose level.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD0

Value:

> 6 852 mg/kg bw

Justification for classification or non-classification

A 90-day repeated dose drinking water study in rats is available, in which no adverse effects were observed up to 6852 mg Cellobiose per kg body weight. The results of the study are used to assess the acute oral toxicity.

As the NOEL is > 6852 mg/kg bw no GHS classification is warranted.