Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

Repeated dose toxicity (oral, subacute): NOEL (male/female) = 250 mg/kg bw/day; NOAEL (male/female) = 1000 mg/kg bw/day (Annex V; Method B7)

Key value for chemical safety assessment

Toxic effect type:
dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records
Reference
Endpoint:
short-term repeated dose toxicity: oral
Type of information:
other: SNIF
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
All information in this endpoint has been provided by the ECHA using the 12-year rule, this is data not owned by the registrant. The reliability is assumed to be at level 2. Therefore the following reliability statement can be used: Study conducted in accordance with generally accepted scientific principles, possibly with incorect reporting or methodological deficiencies, which do not affect the quality of the relevant results.
Qualifier:
according to guideline
Guideline:
EU Method B.7 (Repeated Dose (28 Days) Toxicity (Oral))
Principles of method if other than guideline:
Information from migrated NONS file, as per inquiry number 06-0000021057-76-0000, permission to refer granted by ECHA.
GLP compliance:
not specified
Limit test:
no
Species:
rat
Strain:
other: Charles River Crl : CD(SD)BR strain
Sex:
male/female
Route of administration:
oral: gavage
Vehicle:
other: 1 % aqueous methyl cellulose
Duration of treatment / exposure:
Test duration: 28 days
Frequency of treatment:
7 days per week
Dose / conc.:
62.5 mg/kg bw/day (nominal)
Dose / conc.:
250 mg/kg bw/day (nominal)
Dose / conc.:
1 000 mg/kg bw/day (nominal)
No. of animals per sex per dose:
5 males
5 females
Control animals:
yes
Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
not specified
Food consumption and compound intake (if feeding study):
not examined
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not specified
Haematological findings:
effects observed, treatment-related
Description (incidence and severity):
Mean haemoglobin concentration decreased (p <0.05) in top dose females relative to controls, and was marginally lower than the lower end of the historical value range.
Clinical biochemistry findings:
not specified
Urinalysis findings:
not specified
Behaviour (functional findings):
not specified
Immunological findings:
not specified
Organ weight findings including organ / body weight ratios:
not specified
Gross pathological findings:
no effects observed
Neuropathological findings:
not specified
Histopathological findings: non-neoplastic:
no effects observed
Details on results:
One animal died during blood sampling (anaesthetic trauma).
Dose descriptor:
NOEL
Effect level:
250 mg/kg bw/day (nominal)
Sex:
male/female
Basis for effect level:
other: No effects noted
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day (nominal)
Sex:
male/female
Basis for effect level:
haematology
Critical effects observed:
no
Conclusions:
In a sub-acute toxicity study in Charles River Crl:CD(SD)BR rats, the NOEL (male/female) was 250 mg/kg bw/day and the NOAEL (male/female) was 1000 mg/kg bw/day.
Executive summary:

In a sub-acute toxicity study (Annex V; Method B7), DL-N33 was administered by oral gavage to Charles River Crl:CD(SD)BR rats (5/sex/group) in 1% aqueous methylcellulose at 0, 62.5, 250 or 1000 mg/kg bw/day for 28 days, 7 days per week.

No treatment-related deaths or clinical signs of toxicity. Mean haemoglobin concentration decreased (p <0.05) in top dose females relative to controls, and was marginally lower

than the lower end of the historical value range. No other treatment-related effects were observed. No gross or microscopic treatment-related effects were observed.

The NOEL (male/female) was 250 mg/kg bw/day and the NOAEL (male/female) was 1000 mg/kg bw/day.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
1 000 mg/kg bw/day
Study duration:
subacute
Species:
rat
Quality of whole database:
There is one study available and it has a Klimisch score of 2.

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Repeated dose toxicity (oral)

There is one 28 day repeated dose toxicity study in rats available.

In a sub-acute toxicity study (Annex V; Method B7), DL-N33 was administered by oral gavage to Charles River Crl:CD(SD)BR rats (5/sex/group) in 1% aqueous methylcellulose at 0, 62.5, 250 or 1000 mg/kg bw/day for 28 days, 7 days per week. No treatment-related deaths or clinical signs of toxicity. Mean haemoglobin concentration decreased (p <0.05) in top dose females relative to controls, and was marginally lower than the lower end of the historical value range. No other treatment-related effects were observed. No gross or microscopic treatment-related effects were observed. The NOEL (male/female) was 250 mg/kg bw/day and the NOAEL (male/female) was 1000 mg/kg bw/day.

This study is acceptable to use in the human health risk assessment.

Justification for classification or non-classification

Based on the available information in the dossier, the substance DL-N33 (CAS No. 104815-18-1) does not need to be classified as specific target organ toxicity (repeated) when considering the criteria outlined in Annex I of 1272/2008/EC.