Registration Dossier

Diss Factsheets

Toxicological information

Toxicity to reproduction

Currently viewing:

Administrative data

toxicity to reproduction
other: subchronic feeding study
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was performed similar to OECD guideline 409 and under GLP-like quality controlled conditions with QAU statement provided.
Reason / purpose for cross-reference:
reference to same study

Data source

Reference Type:
study report
Report date:

Materials and methods

Principles of method if other than guideline:
90 day feeding study similar to OECD 409
GLP compliance:
but with QAU statement.

Test material

Constituent 1
Chemical structure
Reference substance name:
Calcium diethyl bis[[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate]
EC Number:
EC Name:
Calcium diethyl bis[[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate]
Cas Number:
Molecular formula:
C17 H29 O4 P. 1/2Ca
calcium diethyl bis[[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate]
Details on test material:
Physical appearance: white, solid powder

Test animals

other: dog
other: Beagle
Details on test animals or test system and environmental conditions:
- Source: Balbeggie Kennels, Fife, Scotland
- Age at arrival: 20-22 weeks
- Weight at study initiation: 5.2-9.1 kg
- Identification: tattoo on the right hind limb
- Housing: individually housed in indoor kennels measuring 0.7 x 1.6 m and equipped with under-floor heating. Brief periods of supervised exercise were permitted daily and more extended periods of up to six hours were allowed approximately weekly, in covered outside runs.
- Diet: A moistened powdered dog diet (Laboratory Diet A from BP Nutrition Products Ltd., Witham, Essex, England) was offered as two 300 g meals given three hours apart at approximately the same times daily and any food uneaten was withdrawn the following morning.
- Acclimation period: 19 weeks without treatment before assignment to this study, an additional 15 weeks after assignment before the commencement of treatment. The replacement animal was 82 weeks old and had been held without treatment for a total of 55 weeks.

- Temperature (°C): mean daily maximum = 19°± 2°C, mean daily minimum = 13° ± 4°C
- Humidity (%): 78±8
- Photoperiod: 12 hrs dark / 12 hrs light
- Air changes: 15 per hour

Administration / exposure

Route of administration:
oral: feed
unchanged (no vehicle)
Details on exposure:
On the first four occasions of formulation, the initial dispersal of the test substance into dry powdered diet was made by mixing the required quantity of the test substance with 100 g of diet in a Kenwood planetary mixer. Thereafter this was achieved by shaking the constituents of the admixture in a closed container and homogenising this product by passage through a grinder. This modification was adopted to minimise the generation of dust and hence possible loss of compound. The resulting pre-mix was further diluted with dry powdered diet in a Kenwood Chef planetary mixer for ten minutes followed by further dilution with diet in a Hobart A200 planetary mixer (15 minutes) to give a final pre-mix of 8800 ppm. The final admixtures for Group 3 (600 ppm) and Group 4 (2000 ppm) were achieved by diluting the required amount of pre-mix with diet in a Gardner 50L trough mixer with interrupted spiral agitator (15 minutes). The final admixture for Group 2 (200 ppm) was achieved by prediluting the required amount of pre-mix with diet in a Hobart A200 planetary mixer (ten minutes) with a final dilution with diet in the Gardner trough mixer (15 minutes). Each product, and untreated control diet, was wetted with tap water (200 mL/kg): and mixed in the Gardner trough mixer (15 minutes). At the request of the Sponsor, the mixing times were extended from 17 January 1980 (Week 12) by five minutes for each mixing procedure (excluding the wetting stage) involving the Kenwood planetary, Hobart A200 planetary and Gardner trough mixers. The final products were stored at 4°C for no more than four days and issued daily to the animal house.

- Rate of preparation of diet (frequency): at least every 4 days
- Storage temperature of food: 4°C
Details on mating procedure:
no mating performed
Analytical verification of doses or concentrations:
Details on analytical verification of doses or concentrations:
Samples of the unwetted diet (200 g of the single common pre-mix and of each test group final mix and 500 g of control diets) prepared before the commencement of treatment and for use in weeks 1, 5, 8/9, 13 and the last week of treatment were supplied to the sponsor for analysis. In addition, a further 50 g sample of each test diet was retained for at least three months in sealed polythene sachets and stored at room temperature in these laboratories pending possible future analysis as required by Section 58.113 of the Good Laboratory Practice regulations. These samples were not analysed and were eventually discarded.
Duration of treatment / exposure:
7 days/week; 13 weeks
Frequency of treatment:
Continuous dosing with feed.
Doses / concentrationsopen allclose all
Doses / Concentrations:
200, 600, 2000 ppm
nominal in diet
Doses / Concentrations:
8.5, 24.7, 84.1 mg/kg bw/day (males)
actual ingested
Doses / Concentrations:
9.2, 28.3, 90.2 mg/kg bw/day (females)
actual ingested
No. of animals per sex per dose:
6 animals per sex and dose
Control animals:
yes, plain diet


Postmortem examinations (parental animals):
All animals were subjected to a detailed necropsy involving the opening of the cranial, thoracic and abdominal cavities.

The following organs were dissected free of fat and other adjacent tissue before being weighed: Testes, Ovaries, Adrenals, Brain, Heart, Kidneys, Liver, Spleen, Thyroids. The ratio of organ weight to bodyweight was calculated in each case.

The following tissues were examined microsopically: Testes, Epididymides, Ovaries, Uterus, Uterine cervix, Adrenals, Aorta (thoracic), Brain, Colon, Duodenum, Eyes and optic nerves, Gall bladder, Heart (auricle, ventricle, ventricular septum, Ileum, Jejunum, Kidneys, Liver, Lungs (including mainstem bronchi), Lymph nodes (axillary, cervical, mesenteric), Mammary gland (caudal, cranial), Oesophagus, Pancreas, Parathyroids, Pituitary, Prostate, Salivary glands (left), Sciatic nerve (left), Skeletal muscle (thigh), Skin (dorsum), Spinal cord (cervical region, lumbar region), Spleen, Sternum, Stomach (cardia, fundus, pyloru), Thymus, Thyroids, Tongue, Trachea, Urinary bladder.

Results and discussion

Results: P0 (first parental generation)

Details on results (P0)

Comparison of organ weights, expressed either in absolute or bodyweight-relative terms gave no indication of any differences attributable to the administration of the test substance. Specifically, reproductive organs did not show any deviations from control animals.

No changes to reproductive organs were detected that could be related to treatment with the test substance. Two male dogs in the highest dosage group had a unilateral juvenile epididymis and testis due to cryptorchidism.

Effect levels (P0)

open allclose all
Dose descriptor:
Effect level:
84.1 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
other: high dose
Dose descriptor:
Effect level:
90.2 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
other: high dose

Overall reproductive toxicity

Reproductive effects observed:
not specified

Applicant's summary and conclusion

Categories Display