Registration Dossier

Classification & Labelling & PBT assessment

DSD-DPD

General information

Name:
Potassium silicate lumps, powders or aqueous solutions of molar ratio <= 1.6
Status:
67/548/EEC self classification
Remarks:
Potassium silicate is manufactured in various molar ratios as lumps, powders or aqueous solutions (see technological process). Molar ratios (MR) define the ratio of SiO2 versus K20 in the substance: tetrahedra of the silicon-oxide anion SiO42- as the basic structural units are linked with each other via Si-O-Si bonds resulting in an infinite three-dimensional network. The negative charge of unshared oxygen atoms is balanced by the presence of potassium cations which are randomly spaced in the interstices. The extent to which balancing potassium ions are present in a given silicate is defined by the molar ratio SiO2/K2O. The higher the molar ratio, the less potassium ions are present in the silica network and consequently the less alkaline the silicates are. Therefore, classification & labeling depends on the molar ratio. From the molar ratio the concentrations of SiO2 and K2O can be calculated. The concentration of K2O can be taken as a measure for the skin and eye irritation potency. The relationship between molar ratios, specific concentration limits and classification & labeling is as follows: Molar ratio (MR) <=1.6 SiO2 <=50% K2O >=50% -->C, R34 (solutions); C, R34, 37 (powders) MR >1.6 - 2.6 SiO2 >50 - 62% K2O <50 - 38% --> Xi, R38, 41 (solutions); Xi, R37/38, 41 (powders) MR >2.6 SiO2 >62% K2O <38% --> Xi, R36/38 (solutions); Xi, R36/37/38 (powders) MR >3.2 SiO2 >67% K2O <33% --> no C&L (only lumps and aqueous solutions with solids concentration <40%)

Related composition

Related composition:
Composition 19

Classification

Explosiveness

Reason for no classification:
data conclusive but not sufficient for classification

Oxidising properties

Reason for no classification:
data conclusive but not sufficient for classification

Flammability

Reason for no classification:
data conclusive but not sufficient for classification

Thermal stability

Reason for no classification:
data conclusive but not sufficient for classification

Acute toxicity

Reason for no classification:
data conclusive but not sufficient for classification

Acute toxicity - irreversible damage after single exposure

Reason for no classification:
data conclusive but not sufficient for classification

Repeated dose toxicity

Reason for no classification:
data conclusive but not sufficient for classification

Irritation / corrosion

Classification:
C; R34 Causes burns.
Xi; R37 Irritating to respiratory system

Sensitisation

Reason for no classification:
data conclusive but not sufficient for classification

Carcinogenicity

Reason for no classification:
data conclusive but not sufficient for classification

Mutagenicity - genetic toxicity

Reason for no classification:
data conclusive but not sufficient for classification

Toxicity to reproduction - fertility

Reason for no classification:
data conclusive but not sufficient for classification

Toxicity to reproduction - development

Reason for no classification:
data conclusive but not sufficient for classification

Toxicity to reproduction - breastfed babies

Reason for no classification:
data conclusive but not sufficient for classification

Environment

Reason for no classification:
data conclusive but not sufficient for classification

Labelling

Indication of danger

C - corrosive

Risk phrases

R34 - Causes burns
R37 - Irritating to respiratory system

Safety phrases

S22 - do not breathe dust
Only applies to the powders. Consequently, the risk phrase R37 also only applies to the powders.
S26 - in case of contact with eyes, rinse immediately with plenty of water and seek medical advice
S36/37/39 - wear suitable protective clothing, gloves and eye/face protection
S45 - in case of accident or if you feel unwell, seek medical advice immediately (show the label where possible)

Specific concentration limits

1. Concentration range (%):
38 - < 50
Classification:
Xi; R38 Irritating to skin.
Xi; R41 Risk of serious damage to eyes.
Xi; R37/38 Irritating to respiratory system and skin
2. Concentration range (%):
< 38
Classification:
Xi; R36/38 Irritating to eyes and skin.
Xi; R36/37/38 Irritating to eyes, respiratory system and skin.
3. Concentration range (%):
< 33

Notes