Anode, copper

Toxicological Summary

Workers - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

medium hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

low hazard (no threshold derived)

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

medium hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

low hazard (no threshold derived)

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:

no hazard identified

Additional information - workers

The hazard assessment of inorganic UVCBs for the purpose of classification and derivation of threshold values (i.e. DNELs) is a complex process. Due to the variability of the composition of an UVCB, it is not possible to select a sample that would be representative for the hazard profile of the UVCB and could subsequently be used for toxicity testing. Instead of testing, a precautionary approach is followed in which the UVCB nature of a complex metal containing substance having a number of constituents (metals and their compounds or other inorganic compounds) is acknowledged. The hazard profile of each individual constituent is used for deriving the classification of the UVCB (using the mixture rules) and for the derivation of the DNELs of the constituent. Using the unmodified DNEL values of all individual constituents addresses the varying composition of an UVCB on a pre-cautionary basis as it implicitly assumes that the UVCB entirely consists of the specific constituent, i.e. that each constituent would be present to 100% in the UVCB. Thus, this hazard assessment can be considered a conservative approach. The identification of constituents which are hazardous for human health also defines the scope of the exposure assessment and risk characterisation (Chapters 9 & 10).

 

The hazard profile of the inorganic UVCB and the individual constituents is dependent on their chemical speciation.Depending on the level of knowledge, the following situations can be distinguished:

 

·      If chemical speciation of the constituent in the UVCB is known, this is used for classification.

·      If chemical speciation of the constituent as present in the workplace is known, this is used for risk characterisation.

·      When information on chemical speciation is not complete, the worst-case speciation for the purpose of risk characterisation and classificationis assumed, i.e. the speciation that would lead to the most severe classification or to the lowest DNEL.It is noted that different chemical species could be relevant (see below).

 

Selection of toxicological information for classification

 

The UVCB classification is calculated by applying the CLP mixture rules based on the classification of the known or worst-case speciation of each constituent and worst-case constituent concentration in the UVCB (i.e. the maximum value of the typical concentration reported by the individual legal entities), using the MeClas tool.

 

Selection of toxicological information for risk assessment

 

For the purpose of the human health risk assessment for the UVCB, the hazards of each constituent will be assessed and DNEL values for constituents for which a hazard has been identified are compiled. As indicated above, workers may be exposed to different chemical species compared to those present in the UVCB. Hence, the information onthe intrinsic properties of the UVCB constituents relevant for classification can be refined if it is known which chemical species is present in the workplace. If speciation is unknown, the chemical species of an individual constituent is considered having the lowest DNEL which could be different when compared to the species used for classification.

 

For the sake of readability of the CSR and the IUCLID, the below sections therefore outlinetoxicity effects derived for the UVCB itself. Information on hazards linked to speciation occurring in case individual constituing species of the UVCB (see CSR 3.0 Introduction to Classification) are released during production/use of the UVCB are reported in a separate annex of this CSR, if deemed relevant for the risk assessment.

The UVCB is a complex inorganic metals containing substance. The physico-chemical characterization of the UVCB (see relevant section in IUCLID) demonstrates that metal and intermetallic species resulted in sparingly to low solubilisation potential in water for most of the metals present in the UVCB (eg Cu, Pb, Ni). Metals emitted/released when the UVCB was dissolved in gastric and sweat fluids confirm that most constituents are not readily available from the UVCB.

 

Hazard conclusions for the purpose of classification

 

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. The classification was derived using Meclas (MEtals CLASsification tool - see www.meclas.eu), a calculation tool that follows classification guidance and implementation in accordance to legal rules and technical guidance from ECHA and CLP see IUCLID section 13 attachment for MeClas Classification conclusions.

 

Table37:Summary of the information on toxicological information for the purpose of classification

UVCB constituent			Variabiliy of elemental composition	Classification according each relevant endpoint
Element	Speciation* in composition   Speciation taken forward for human health Tier 1 classification (inhalation and dermal route endpoints)	Speciation taken forward for Tier 2 human health classification (oral and dermal route endpoints)
Cu	98.39% Cu massive 1.61% Cu2O (Grade 2)0.8% Cu2O (Grade 1)	Copper sulphate	Maximum of typicals	Harmonised and worse self- classification of the speciation, see MECLAS report in CSR Annex I
Pb	Pb compounds	Pb compounds	Maximum of typicals	Harmonised and worse self- classification of the speciation, see MECLAS report in CSR Annex I
As	As compounds	As compounds	Maximum of typicals	Harmonised classification of the speciation, see MECLAS report in CSR Annex I
Ni	Ni massive	Same as speciation Tier 1 (no bio-availability correction)	Maximum of typicals	Harmonised classification of the speciation, see MECLAS report in CSR Annex I
Fe	Fe massive	Same as speciation Tier 1 (no bio-availability correction)	Maximum of typicals	Not classified, see MECLAS report in CSR Annex I
Si	Si	Same as speciation Tier 1 (no bio-availability co	Maximum of typicals	Not classified, see MECLAS report in CSR Annex I
Other Minors: Ag, Al, Au, Bi, Cd, Co, Sb, Sn, Se, Pd, Pt, Te	Sulphide/compounds or metal	Same as speciation Tier 1 (no bio-availability correction)	Maximum of typicals	Below 0.1% and/or the speciation not impacting classification, see MECLAS report in CSR Annex I

* see IUCLID/CSR section 1.2 composition and IUCLID 4.23 additional Physico-chemical Information

 

Selection of the DNEL(s) for the purpose of risk assessment

 

The UVCB is an intermediate, with a very limited life cycle (manufacturing and industrial uses only). Testing the UVCB is difficult because of the large uncertainty involved when selecting representative samples due to the variable elemental concentrations in the composition of the UVCB.Derivation of a DNEL for the UVCB as such is thereforedifficult to interpretand to extrapolate results of testing to the entirety of variations of the UVCBbecause of the uncertainty related to the representativeness of the testing.Exposure to the UVCB cannot be measured or modelled and expressed as portion of the UVCB emitted because of the multi-constituent character of the UVCB. For these reasons, the UVCB toxicological assessment is driven by the assessment of the individual UVCB constituents.

 

The human health assessment is based on all hazardous constituents for human health of all relevant UVCBs in the workplace. The scope of the exposure assessment and type of risk characterization required for workers for each constituent is described in section 9 of this CSR.

 

Table38:Summary of the information on toxicological information for the purpose of risk assessment

UVCB constituent		Variability in chemical composition	DNELs for systemic and local effects, inhalation and dermal route, short term and long term.
Element	Speciation used for occupational exposure assessment
Cu	Cu ion is toxic driver	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in IUCLID and table below
Fe	Fe ion is toxic driver	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in IUCLID and table below
Ni	Ni ion is toxic driver except NiSO4for systemic acute inhalation and NiS for local acute inhalation	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in IUCLID and table below
Pb	Pb ion is toxic driver	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in IUCLID and table below
As	As ion is toxic driver	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in IUCLID and table below
Si	Non-crystalline silica speciation	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in table below
Other Minors: Ag, Al, Au, Bi, Cd, Co, Sb, Sn, Se, Pd, Pt, Te	Speciation with worst-case DNEL	Hazard assumed as if UVCB consists of 100% worst-case speciation	See respective DNEL summary in table below

  

Different speciation is relevant to consider. In some cases, human health toxicity is driven by free metal ion. In other cases, human health toxicity is different per species and since the speciation of the exposure is not always known, the species with the worst-case DNEL was further considered for the assessment. Toxicological information on the individual UVCB constituents is reported in each constituent summary for which a quantitative exposure and risk assessment was conducted (the information is taken from the respective constituent IUCLID dossiers).

 

The relevant copper speciations for occupational exposure are Cu²⁺ion, CuSO₄, Cu₂O and CuO. There is no difference between the DNEL values of these speciations (apart from the molecular weight conversion). The DNEL values are therefore based on the soluble form. There is no separate DNEL derived for powder form. The common DNEL values are taken forward to risk characterisation.

 

The relevant lead speciations for occupational exposure are lead metal, lead oxide and lead sulfate. All DNELs are based upon systemic biomarkers of exposure and not on external exposure. The DNEL values used for occupational exposure assessment are therefore based on internal concentration of soluble lead concentrations.

 

Workers can be exposed to arsenic under different speciations i.e. arsenic metal, arsenic sulfide, arsenic sulphate and diarsenic trioxide. Only DNEL values are available for diarsenic trioxide. It is assumed that the arsenic ion is the driver for toxicity. The DNEL for arsenic can therefore be calculated based on the DNEL of arsenic oxide using the molecular weight conversion. These recalculated DNEL values are used for the risk assessment of arsenic. The same rationale holds for antimony.

 

The relevant nickel speciations are Ni metal, Ni sulphates, Ni sulfide and Ni oxide. There are differences in DNEL values between these speciations for a few type of effects. The DNEL values of the worst-case speciation form are therefore taken forward to risk characterisation. Ni sulphate has the lowest systemic acute inhalation DNEL of 16 mg Ni/m³(16-680 mg Ni/m³). Ni sulfide has a DNEL of 0.47 mg/m³for the local acute inhalation effects (range 0.47-4 mg Ni/m³). The local long-term dermal DNEL of 0.00044 mg Ni/cm²/day (range 0.00044 -0.07 mg Ni/cm²/day) is taken forward to risk characterisation.

 

Zn substances are divided in 2 solubility groups: “soluble” substances or “slightly soluble”/“insoluble” substances. The “soluble” DNEL values are selected since these have the lowest (worst-case) DNEL values.

 

During pyrometallurgical processs, Metal sulphides are oxidised and transformed into SO₂. The SO₂DNEL values are therefore taken forward for the occupational effect assessment and risk characterisation.

 

SnSO₄has the lowest DNEL values compared to SnS and Sn metal and are taken forward to risk characterisation. For the other elements such as Co and Ba, the same approach has been taken for the relevant metallic, sulfide, sulfate, and oxide speciations.

 

Carbon is speciated as charcoal. There are no other relevant speciations to consider. For silicate and aluminates, non-crystaline metal and oxide speciations are considered. Toxicological effects can be attributed to Al ion. Chromium is in the trivalent form.

 

For Ca, Mg, K and Na, these elements are considered to be non-hazardous at the levels of potential exposure. Any potential toxicological effects from these elements are due to the oxide or sulphate speciation. These effects are already covered by the existing metal elements.

General Population - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

low hazard (no threshold derived)

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

low hazard (no threshold derived)

DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

low hazard (no threshold derived)

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

General Population - Hazard via oral route

Systemic effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

low hazard (no threshold derived)

DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:

no hazard identified

Additional information - General Population

DNELs for the general population are currently not included because an assessment of exposure of man via the environment is not reported but instead considered to be already included in the dossiers of the constituents. However, DNELs for the general population and the assessment of exposure of man via the environment might be amended by further analysis (please refer to Chapter 9.0.2.3. for further details).