fermentation residues of molasses, yeast extract, sucrose and ammonia with bacillus subtilis

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 December 2009 to 15 February 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study has been performed according to OECD 422 guidelines and GLP principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Biomass residue (liquid) obtained after B2 production

IUPAC Name:

Biomass residue (liquid) obtained after B2 production

Test animals

Species:

rat

Strain:

other: Crl:WI(Han)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories France, L'Arbresle Cedex, France
- Age at study initiation: Approximately 11 weeks.
- Fasting period before study: no
- Housing:
Pre-mating: Animals were housed in groups of 5 animals/sex/cage in Macrolon plastic cages (MIV type, height 18 cm).
Mating: Females were caged together with males on a one-to-one-basis in Macrolon plastic cages (MIII type, height 18 cm).
Post-mating: Males were housed in their home cage (Macrolon plastic cages, MIV type, height 18 cm) with a maximum of 5 animals/cage. Females were individually housed in Macrolon plastic cages (MIII type, height 18 cm).
Lactation: Pups were kept with the dam until termination in Macrolon plastic cages (MIII type, height 18 cm).
General: Sterilised sawdust as bedding material (Litalabo, S.P.P.S., Argenteuil, France) and paper as cage-enrichment (Enviro-dri, Wm. Lillico & Son (Wonham Mill Ltd), Surrey, United Kingdom) were supplied. Certificates of analysis were examined and then retained in the NOTOX archives. During activity monitoring, animals were housed individually in Macrolon plastic cages (MIII type; height 15 cm) with sterilised sawdust as bedding material. No cage-enrichment was provided during activity monitoring.

- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: At least 5 days prior to start of treatment under laboratory conditions.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 3°C (actual range: 20.0 ¿ 22.1°C)
- Humidity (%): 40 - 70% (actual range: 28 - 71%)
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: 28 December 2009 to 15 February 2010

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

Elix

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Formulations (w/w) were prepared daily within 6 hours prior to dosing and were homogenised to a visually acceptable level. Adjustment was made for density of the test substance (1.14 g/mL).

VEHICLE
- Concentration in vehicle: 20, 60 and 200 mg/mL
- Amount of vehicle (if gavage): 5 mL/kg body weight. Actual dose volumes were calculated according to the latest body weight.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analyses were conducted on a single occasion during the treatment phase. Samples of formulations were analyzed for homogeneity (highest and lowest concentration) and accuracy of preparation (all concentrations). Stability in vehicle over 6 hours at room temperature was also determined (highest and lowest concentration).
The accuracy of preparation was considered acceptable if the mean measured concentrations were 85-115% of the target concentration. Homogeneity was demonstrated if the coefficient of variation was = 10%. Formulations were considered stable if the relative difference before and after storage was maximally 10%.

Duration of treatment / exposure:

Males were exposed for 28 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 42-49 days, i.e. during 2 weeks prior to mating, during mating, during post-coitum, and during at least 4 days of lactation.

Frequency of treatment:

Once daily for 7 days per week, approximately the same time each day with a maximum of 6 hours difference between the earliest and latest dose. Animals were dosed up to the day prior to scheduled necropsy.

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 100, 300, 1000 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Dose levels were based on results of the dose range finding study (NOTOX Project 492228)

Positive control:

no

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: at least twice daily (early morning/late afternoon)

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at least once daily; at least immediately after dosing. Once prior to start of treatment and at weekly intervals this was also performed outside the home cage in a standard arena. Arena observations were not performed when the animals were mating, or housed individually.

BODY WEIGHT: Yes
- Time schedule for examinations: Males and females were weighed on the first day of exposure and weekly thereafter. Mated females were weighed on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum, and during lactation on Days 1 and 4.

FOOD CONSUMPTION : Yes
Weekly, except for males and females which were housed together for mating and for females without evidence of mating. Food consumption of mated females was measured on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum and on Days 1 and 4 of lactation.

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: Yes

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: immediately prior to scheduled post mortem examination, between 7.00 and 10.30 a.m.
- Anaesthetic used for blood collection: Yes iso-flurane
- Animals fasted: yes, but water was available
- How many animals: 5 males/group (random) and selected females with live pups (7 in Group 1, 6 in Group 2 and 3, and 5 in Group 4).
- Parameters examined were: white blood cells, differential leucocyte count (neutrophils, lymphocytes, monocytes, eosinophils, basophils), red blood cells, reticulocytes, red blood cell distribution width, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, platelets, prothrombin time, activated partial thromboplastin time.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: immediately prior to scheduled post mortem examination, between 7.00 and 10.30 a.m.
- Animals fasted: yes, but water available
- How many animals: 5 males/group (random) and selected females with live pups (8 in Group 1, 6 in Group 2 and 3, and 5 in Group 4)
- Parameters examined were: Alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total protein, albumin, total bilirubin, urea, creatinine, glucose, cholesterol, sodium, potassium, chloride, calcium, inorganic phosphate, bile acids.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: The selected males were tested during Week 4 of treatment and the selected females were tested during lactation (all before blood sampling).
- Dose groups that were examined: all
- Battery of functions tested: hearing ability, pupillary reflex, static righting reflex, grip strength and motor activity

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
All animals were subjected to macroscopic examination of the cranial, thoracic and abdominal tissues and organs, with special attention being paid to the reproductive organs. The number of former implantation sites and corpora lutea was recorded for all paired females.

From all animals, samples of the following tissues and organs were collected and fixed in 10% buffered formalin (neutral phosphate buffered 4% formaldehyde solution, Klinipath, Duiven, The Netherlands):
Identification marks (not processed), Cervix, Clitoral gland, Epididymides*, Ovaries, Preputial gland, Prostate gland, Seminal vesicles including coagulating gland, Testes*, Uterus, Vagina, All gross lesions.

From selected males and females with live pups, samples of the following tissues and organs were collected and fixed in addition to the abovementioned list:
Adrenal glands, Aorta, Brain (cerebellum, mid-brain, cortex), Caecum, Colon, Duodenum, Eyes (including optic nerve and Harderian gland)*, Female mammary gland area, Femur including joint, Heart, Ileum, Jejunum, Kidneys, Lacrimal gland (exorbital), Larynx, Liver, Lung (infused with formalin), Lymph nodes (mandibular, mesenteric), Nasopharynx, Oesophagus, Pancreas, Peyer's patches (jejunum, ileum) if detectable, Pituitary gland, Rectum, Salivary glands (mandibular, sublingual), Sciatic nerve, Skeletal muscle, Skin, Spinal cord (cervical, midthoracic, lumbar), Spleen, Sternum with bone marrow, Stomach, Thymus, Thyroid including parathyroid (if detectable), Tongue, Trachea, Urinary bladder.
*Fixed in modified Davidson's solution and transferred to formalin after fixation for at least 24 hours.

ORGAN WEIGHTS: Yes
The following organ weights and terminal body weight were recorded from selected males and females with live pups on the scheduled day of necropsy:
Adrenal glands, Brain, Epididymides (all males), Heart, Kidneys, Liver, Ovaries Spleen, Testes (all males), Thymus, Uterus (including cervix), Prostate*, Seminal vesicles including coagulating glands*, Thyroid including parathyroid*
* weighed when fixed for at least 24 hours.

HISTOPATHOLOGY: Yes
The following slides were examined by a pathologist:
- The preserved organs and tissues of 5 selected animals/sex of Groups 1 and 4.
- The additional slides of the testes of the selected 5 males of Groups 1 and 4 to examine staging of spermatogenesis.
- All gross lesions of all animals (all dose groups).
- The reproductive organs (cervix, clitoral gland, coagulation gland, epididymides, ovaries, preputial gland, prostate gland, seminal vesicles, testis, uterus, and vagina) of all animals that failed to mate, conceive, sire or deliver healthy pups.

Statistics:

The following statistical methods were used to analyse the data:
- If the variables could be assumed to follow a normal distribution, the Dunnett-test (many-to-one t-test) based on a pooled variance estimate was applied for the comparison of the treated groups and the control groups for each sex. (Dunnett C.W., 1955)
- The Steel-test (many-to-one rank test) was applied if the data could not be assumed to follow a normal distribution. (Miller R.G., 1981)
- The Fisher Exact-test was applied to frequency data. (Fisher R.A., 1950)

The following additional methods of statistical analysis were used:
The numbers of corpora lutea and implantation sites were transformed by using log x and x2, respectively, to obtain a normal distribution. This was followed by an ANOVA. The Dunnett-test (many-to-one t-test) based on a pooled variance estimate was applied for the comparison of the treated groups and the control group.

All tests were two-sided and in all cases p < 0.05 was accepted as the lowest level of significance.

Group means were calculated for continuous data and medians were calculated for discrete data (scores) in the summary tables. Test statistics were calculated on the basis of exact values for means and pooled variances. Individual values, means and standard deviations may have been rounded off before printing. Therefore, two groups may display the same printed means for a given parameter, yet display different test statistics values.
No statistical analysis was performed on histopathology findings.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Effect levels

Dose descriptor:

NOAEL

Effect level:

>= 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects: No parental toxicity was observed at any dose level.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Treatment with Biomass residue obtained after B2 production by oral gavage in male and female Wistar (Han) rats at dose levels of 100, 300 and 1000 mg/kg bw/day revealed no parental toxicity up to 1000 mg/kg bw/day. No reproduction and developmental toxicity was observed for treatment up to 1000 mg/kg bw/day. Based on these results, a parental, reproductive and developmental No Observed Adverse Effect Level (NOAEL) of at least 1000 mg/kg bw/day was derived.