Registration Dossier

Administrative data

Description of key information

- Acute Oral Toxity (LD50, Rat) for SCP liquor is estimated to be > 5000 mg/kg body weight (OECD 423 and EC 440/2008, B.1 tris). 
- According to the CLP regulation 1272/2008 and Comission Directive 2001/59/EC the results of SCP liquor do not indicate need for classification for acute oral toxicity.

Key value for chemical safety assessment

Additional information

SCP liquor did not show acute oral toxicity (LD50 > 5000 mg/kg body weight) in a test performed according to the test guideline B.1 tris (EC 440/2008).

The expected maximum concentration ranges of the identified main components in SCP liquor did not suggest acute oral toxicity of SCP liquor either.

There is no available data on acute dermal or acute inhalation toxicity of SCP liquor. Also here the identified main components in SCP liquor did not suggest acute dermal or acute inhalation toxicity of SCP liquor. However, given as supplemental hazard information it should be noted that the combustion gases of SCP liquor may contain toxic Na2O vapours.

Justification for classification or non-classification

Spent liquor from semi-chemical pulping (SCP liquor) is a process liquor from CTMP and NSSC pulping obtained after treatment of wood raw material with process chemicals. The source materials are softwood, hardwood and process chemicals. Dry substance content of SCP liquor varies from 5 to 77% depending on the degree of evaporation.SCP liquor is a UVCB substance with a fluctuating composition. Therefore the toxicological properties are somewhat variable as well.

No data was found for toxicological endpoints other than that tested in the key study, through extensive literature searches. SCP liquor is registered as a transported isolated intermediate and no testing data outside Annex VII in the REACH regulation is required.

According to the experimental results the acute toxicity properties of SCP liquor were:

- Non-toxic (acute oral)

Additionally, the need for classification according to the CLP and DSD/DPD rules was evaluated based on the maximum expected concentrations of the identified main ingredients reported in the SCP liquor typical composition (1.2). None of the specified components carry a harmonized classification for acute toxicity, and therefore no classification is suggested.

None of the identified main ingredients hold a harmonized classification for any other toxicological impacts either, and there is no experimental evidence or reason to suspect that SCP liquor would cause such impacts. Therefore no classification is suggested.

The proposed classification for acute toxicity, derived from the experimental results and the properties of the main ingredients of SCP liquor is:

CLP:              No class

DSD/DPD:      No class

Supplemental hazard information:

The combustion gases of SCP liquor may contain toxic Na2O vapours.