Registration Dossier

Administrative data

Description of key information

- complex metal containing substance
- water solubility of the substance is poor (for metal constituents)
- classification based on mixture toxicity rules

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Additional information

Results from calculated classification (using mixture toxicity rules) are supported (WoE) by additional consideration from phys chem properties of the UVCB substance.

The UVCB is a complex metal containing substance, which major constituents are sulphuric acid and water. Sulphuric acid is a strong mineral acid that has high affinity to water. It dissociates in water to form sulphate and hydrogen (carbonium) ions. These are the relevant forms to determine hazard properties of the substance. Arsenic was the only constituent with concentration >0.1%, this constituent triggers the acute toxicity of the substance. The maximum across industry were taken to derive the classification of the UVCB.

Justification for classification or non-classification

Acute toxicity (oral): Category 4 H302 (major driving ion: arsenic acid & salts)

Acute toxicity (dermal): not classified

Acute toxicity (inhalation): Category 4 H332 (major driving ion: arsenic acid & salts)

The classification derived is applicable to all Sulphuric acid, waste gas cooling and cleaning, copper smelting.   The tested sample is representative for a worst case , defined within the concentration ranges outlined under IUCLID section 1.2 Self-classification of the UVCB substance (IUCLID Section 2.1 & 2.2) was performed based on below outline:

1. Characterization

The material is accurately described from its chemical composition (concentration ranges across production sites –IUCLID Section 1.2), and the specific speciation data (forms present in solution) obtained for a representative sample (IUCLID Section 4, in particular 4.23). This information is enough to initiate the classification process.

2. Classification by the Mixture Approach

The UVCB is treated as a complex metal containing substance with a number of discrete constituting compounds (metals, metal compounds, non-metal inorganic compounds). The hazard classifications of each compound are then factored into a combined classification of the UVCB as a whole. For health endpoints, UVCB classifications are based on the combined hazards of the compounds whereby additivity or key cut off levels, specified in look-up tables are used, depending on the endpoint and amount of information available for the constituting compounds. For environmental endpoints, additivity and/or summation algorithms are applied to quantitatively estimate the mixture’s toxicity to aquatic organisms. These concepts and rules are incorporated in easy to use IT tools, which can be used to classify the UVCB.

3. Bridging or Read-Across

(Eco)-toxicological data are not available for the specific UVCBs being evaluated. Considering the knowledge and variability in composition, read-across and bridging is done by using  a "representative" mineralogical/speciation analysis"  combined with the  "worst case" metal concentration (across companies)  as a basis for the classification of the UVCB substance (chemical and mineralogical surrogates with similar origin/production process and physical/chemical properties –see IUCLID 1.4 for information on Sampling procedure).

4. Eventual correction

No correction for (bio)availability was made   See furthermore attached documents: Arche CLP tool version June 2010