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Administrative data

Description of key information

Oral (OECD 401), rat: LD50 > 5000 mg/kg bw 

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
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions. Necropsy was not performed in all surviving animals; 2 instead of 3 dose groups were used. Not performed according to GLP. No analytical purity was given in the study report.
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Version / remarks:
adopted in 1987
Deviations:
yes
Remarks:
necropsy was not performed in all surviving animals; 2 instead of 3 dose groups were used
GLP compliance:
no
Test type:
standard acute method
Limit test:
no
Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Age at study initiation: 9 - 14 weeks
- Weight at study initiation: 179 g (males), 165 g (females)
- Fasting period before study: Animals were fasted in the time between 16 h before and 4 h after the application of the test substance.
- Housing: Animals were housed in groups of 5 in Makrolon III cages with dust-free wood bedding.
- Diet: Altromin R1324, ad libitum
- Water: tap water, ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 1.5
- Humidity (%): 60 ± 5
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES:
From: 23 Nov 1981
To: 9 Dec 1981
Route of administration:
oral: gavage
Vehicle:
water
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 20 mL/kg bw
Doses:
3100 and 5000 mg/kg bw
No. of animals per sex per dose:
5
Control animals:
other: not required
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: On the treatment day, the animals were observed several times for clinical signs. During the residual time of the study period, observations were made twice daily and on weekends and holidays once daily. Animal body weights were determined weekly.
- Necropsy of survivors performed: yes, on a random basis
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 5 000 mg/kg bw
Based on:
test mat.
Mortality:
3100 mg/kg bw: 0/5 males and 0/5 females died.
5000 mg/kg bw: 2/5 males (at 8 and 24 h post-dose) and 0/5 females died
Clinical signs:
3100 mg/kg bw: No clinical signs were observed up to the end of the 14 day observation period.
5000 mg/kg bw: During the first 24 h after application, 5/5 males and 5/5 females layed down in side or prone position and showed signs of sedation. These symptoms were fully reversible within 24 h in all animals. During the residual observation period no symptoms were noted.
Gross pathology:
Necropsy of surviving animals on a radom basis revealed no substance-related findings. No necropsy or histopahological examination was done in the males, died 8 and 24 h post-dose.
Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
CLP: not classified
DSD: not classified
Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
5 000 mg/kg bw
Quality of whole database:
The study has Klimisch score 2.

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

In an acute oral toxicity study performed according to OECD 401, 2 groups of 5 male and 5 female Wistar rats were treated with sodium methylparaben (Loeser, 1982). The test substance was applied in doses of 3100 mg/kg bw and 5000 mg/kg bw as an aqueous solution by oral gavage. No mortality occurred in the group dosed with 3100 mg/kg bw. In the group treated with 5000 mg/kg bw, 2/5 males died during the first 24 h post-dose. All females of the high dose group survived.

No clinical signs were observed in any animal of the low dose group during the 14 d observation period. All males and females of the high dose group showed signs of sedation and layed down in side or prone position during the first 24 h after treatment. Until the end of the 14 d observation period, no other clinical signs were observed in any animal of the high dose group. Necropsy of the surviving animals on a random basis did not reveal any abnormalities.

Therefore, the LD50 is > 5000 mg/kg bw for male and female rats.


Justification for selection of acute toxicity – oral endpoint
There is only one study on sodium methylparaben available. This study is reliable.

Justification for classification or non-classification

The available data on the acute oral toxicity of the test substance does not meet the criteria for classification according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and is therefore conclusive but not sufficient for classification.