Registration Dossier

Administrative data

basic toxicokinetics, other
Information that are available from 28 d study
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study

Data source

Reference Type:
study report
Report Date:

Materials and methods

Test guideline
according to
other: OECD 407
As none of the deviations were rated as critical, deviation notes were not issued. The study report reflects the deviations in an appropriate way.
GLP compliance:
yes (incl. certificate)

Test material

Test material form:
solid: particulate/powder
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): N,N'-hexane-1 ,6-diylbis(hexahydro-2-oxo-1 H-azepine-1-carboxamide)
- Substance type: organic substance
- Physical state: solid
- Analytical purity: 100%
- Lot/batch No.: 07112601
- Storage condition of test material: Room temperature (20°C ± 5°C), dry
- Other:
The test item arrived at NewLab BioQuality GmbH on 07 January 2008 at ambient
temperature and was stored at room temperature on a cJosed shelf upon arrival. Additional
test item of the same batch arrived at NewLab BioQuality GmbH on 11 March 2008 at
ambient temperature and was stored at room temperature on a closed shelf upon arrival.

Test animals

Details on test animals and environmental conditions:
- Source: Harlan Winkel mann GmbH, Gartenstraße 27, 33178 Borehen, Germany
- Age at study initiation: 5 - 8 weeks
- Weight at study initiation: males: 167 to 175 grams (mean), females: 151 to 159 grams (mean)
- Fasting period before study: no
- Housing: Clean conventional housing: aeration with approx. 10 air changes per hour, room climate 22 ± 3°C at 30-70% relative humidity, artificial lighting , 12 h Iight / 12 h dark
Eight groups of five animals each in open makroion cages type 2000P (TechniPlast)
Lignocel hygienic animal bedding (J. Rettenmaier & Söhne GmbH + Co. KG, 73494 Rosenberg)
- Diet (e.g. ad libitum): Maintenance diet rat/mouse, pellets, No. 1324 (Altromin GmbH & Co. KG, 32791 Lage), ad /ib.
- Water (e.g. ad libitum): Autoclaved community tap water, ad lib.
- Acclimation period: 8 days (male) / 9 days (female)

- Temperature (°C): 22 ± 3°C
- Humidity (%): 30-70% relative humidity
- Air changes (per hr): 10 air changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
corn oil
Details on exposure:

- Rate of preparation of diet (frequency): daily
- Mixing appropriate amounts with (Type of food): corn oil

- Justification for use and choice of vehicle (if other than water): test item has low solubility in water
- Amount of vehicle (if gavage): The test solutions were intended for an application volume of 8 ml per kg body weight.
Duration and frequency of treatment / exposure:
28 days
Doses / concentrations
Doses / Concentrations:
0 / 63 /250 / 1000 mg/kw bw
No. of animals per sex per dose:
Control animals:
yes, concurrent vehicle
Positive control:
Details on study design:
- Dose selection rationale:
Prior to this study, an acute oral toxicity study according to OECD 401 was performed in rats, which resulted in an LD50 of more than 2000 mg/kg body weight.
In a previously performed dose range finding study with dose escalation, the test item was administered in doses up to 2000 mg/kg body weight over a time period of 19 days and produced no observable toxic effects in the test animals. For this study, a high dose of 1000 mg/kg body weight was determined on request of the sponsor.
- Rationale for animal assignment (if not random):
On the day of arrival, the animals were caged in groups of five according to the following
stratification protocol: rats were weighed individually and grouped into weight categories, the
main group consisting of animals weighing between 100 g and 120 g. These were placed
consecutively into prepared cages. Rats weighing more than 120 g, but not more than 140 g,
were caged similarly after the main weight group was placed. At the time point of
stratification, no rat weighed less than 100 g or more than 120 g.

Results and discussion

Toxicokinetic / pharmacokinetic studies

Details on absorption:
no data available
Details on distribution in tissues:
Biochemical parameters (cholesterol and albumin/globulin ratio) suggest the liver to be the main target organ for the substance.
Details on excretion:
no data available

Metabolite characterisation studies

Metabolites identified:
not measured
Details on metabolites:
no data available


Bioaccessibility testing results:
no data available

Applicant's summary and conclusion

Interpretation of results (migrated information): bioaccumulation potential cannot be judged based on study results
The repeated daily oral administration of N,N'-hexane-1 ,5-diylbis(hexahydro-2-oxo-1 H-azepine-
1-carboxamide) to Wistar-Unilever rats at dose levels of 1000, 250, and 63 mg/kg
bodyweight for a treatment period of 28 days produced mild treatment-related alterations in
the liver of the high dose groups.
Executive summary:

Analysis of hematology and serum biochemistry showed normal results in most instances.

The blood parameters of male animals treated with the test item showed erratic and few significant alterations when compared to the vehicle control group. Chloride and the blood clotting time were slightly raised in the high dose group. In the medium dose group, MCHC was slightly raised and reticulocytes and Albumin was slightly lowered in comparison to their control group. The low dose group showed slightly elevated numbers of segmented neutrophiles and a slightly decreased number of Iymphocytes. All parameters measured in the blood of the male animals were without pathological findings. The most prominent effects of the females of the high dose group and the medium dose group were a significantly raised level of cholesterol and of globulin, indicating liver stress.

The raised levels of total protein and of the albumin/globulin ratio of the high dose group and, milder, in the medium dose group when compared to the vehicle control group also point to the liver as main target of the test item. A slight increase of monocytes and leucocytes was restricted to the female high dose group and possibly indicates a mild effect of liver stress.

Although some significant changes were observed, none of the observed average data points were overall extremely out of range for rats of this strain and age. Other biochemical parameters and the blood cell counts showed no significant differences among the groups.