Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2010-09-15 to 2009-11-12
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study according to OECD 423 guideline and performed under GLP conditions. No deviations.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009
Report Date:
2009

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
acute toxic class method

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
-Beryllium Metal Powder
-Dark grey powder
-Batch number: 0-30 H grade/Blend #051106
-Purity: 99.4 %
-Stability: Stable under storage conditions
-Expiry date: 31 December 2050

Test animals

Species:
rat
Strain:
other: RccHan: WIST (SPF)
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Laboratories, Netherlands
- Age at study initiation: 10 weeks
- Weight at study initiation: 173.6-195.4g
- Fasting period before study: Overnight before dose and 3-4 hours post dose
- Housing: Makrolon type-4 cage with wire mesh tops and standard softwood bedding
- Diet (e.g. ad libitum): Provimi Kliba 3433
- Water (e.g. ad libitum):Tap water (bacteriological, chemical and contaminant analyses are archived with Harlan Laboratories)
- Acclimation period: Period not stated. Only animals without visible signs of illness were used


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+/-3 C
- Humidity (%): 30-70%
- Air changes (per hr): 10-15/hour
- Photoperiod (hrs dark / hrs light): 12 light/12 dark


IN-LIFE DATES: From: 23-09-2009 To: 15-10-2009

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
polyethylene glycol
Details on oral exposure:
A single dose was administered per oral gavage after fasting for 17-19 hours. Dosing volume was 10 ml/kg bodyweight.
Doses:
2000 mg/kg bodyweight
No. of animals per sex per dose:
6
Details on study design:
Study was done according to OECD guideline 423. Two groups of 3 female animals each were administerd Beryllium metal in PEG-300 at a dose of 2000 mg/kg bodyweight. Animals were examined for clinical signs within the first 30 minutes of administration and then at 1, 2, 3, and 5 hours on the the same day. The animals were then observed twice daily from day 2-15. Bodyweight was recorded on day 1 (before administration) and then on day 8 and 15. Animals were subject to necropsy following at the termination of the study.
Statistics:
No statistical analysis performed.

Results and discussion

Effect levels
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Mortality:
No mortality was observed
Clinical signs:
No clinical signs were observed
Body weight:
Bodyweight was within the range of what is observed for this strain (please see table below)
Gross pathology:
No macroscopic findings were recorded at necropsy
Other findings:
Feces was stained gray the day after application

Any other information on results incl. tables

Table 1 Mortality

 Dose level  Group Animal number   Mortality
 2000 mg/kg bodyweight  1 1 -3 
 2000 mg/kg bodyweight  2 4 -6 

Table 2 Bodyweight

 Group Animal  Day 1  Day 8  Day 15 
 Group 1                 1  183.9  206.8  228.3
 2  190.8  208.5  219.6
 3  195.4  211.2  220.6
 Mean  190.0  208.8  222.8
 S.D.  5.8  2.2  4.8
 N  3  3  3
Group 2                  4  188.4  213.9  225.9
 5  173.6  188.4  201.8
 6  182.3  205.6  215.4
 Mean  181.4  202.6  214.4
 S.D.  7.4  13.0  12.1
 N  3  3  3
         

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information LD50 > 2000 mg/kg bodyweight Criteria used for interpretation of results: EU
Conclusions:
The median lethal dose of beryllium metal powder after single oral administration to female rats is greater than 2000 mg/kg bodyweight.
Executive summary:

Two groups of female rats (2 x 3 animals) were administered a dose of 2000 mg/kg bodyweight of beryllium metal powder in polyethylene glycol 300. The animals were examined during the first 30 minutes after administration and then at 1, 2, 3, 5 hours. From day 2 -15 the animals were observed twice daily. Bodyweight was recorded at the day of the study (before administration) and then on day 8 and 15. The animals were then subject to necropsy at the end of the study.

No mortality was observed. There were no clinical signs reported and bodyweight was within the range of what is normal for this strain and age. Necropsy did not reveal any significant findings. The LD50 of beryllium metal powder is > 2000 mg/kg bodyweight.