Cobalt titanite green spinel

Toxicological Summary

Workers - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

other toxicological threshold

Value:

1 mg/m³

Route of original study:

By inhalation

DNEL related information

DNEL derivation method:

other: SCOEL recommended by EC scientific committee

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

DNEL (Derived No Effect Level)

Value:

33.3 mg/kg bw/day

Most sensitive endpoint:

developmental toxicity / teratogenicity

Route of original study:

Oral

DNEL related information

DNEL derivation method:

ECHA REACH Guidance

Overall assessment factor (AF):

300

Modified dose descriptor starting point:

NOAEL

Value:

10 000 mg/kg bw/day

Explanation for the modification of the dose descriptor starting point:

There are no relevant experimental data on repeated dermal exposure. Dermal absorption is anticipated to be 10 % of oral NOAEL as worst case assumption.

AF for dose response relationship:

1

Justification:

The dose response relationship is considered unremarkable, therefore no additional factor is used.

AF for differences in duration of exposure:

6

Justification:

The default extrapolation factor for exposure duration is used: subacute (starting point) to chronic (end point).

AF for interspecies differences (allometric scaling):

4

Justification:

The default allometric scaling factor for the differences between rats and humans is used.

AF for other interspecies differences:

2.5

Justification:

Recommended AF for other interspecies differences.

AF for intraspecies differences:

5

Justification:

The default value for the relatively homogenous group "worker" is used.

AF for the quality of the whole database:

1

Justification:

The quality of the whole data base is considered to be sufficient and uncritical.

AF for remaining uncertainties:

1

Justification:

The approach used for DNEL derivation is conservative. No further assessment factors are required.

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:

no hazard identified

Additional information - workers

Generally data for C.I. Pigment Green 50 are not available. Instead study data of C.I. Pigment Yellow 53 (nickel antimony titanium yellow) was chosen for read across. For further details please refer to read across statements in the respective endpoint summaries.

 

Acute, systemic DNEL

Short term DNELs are not required as the acute toxicity of the test substance is low. The test substance is not classified and labelled for acute systemic toxicity, according to Directive 67/548/EEC (DSD) and Regulation 1272/2008/EC (CLP), based on the test data for acute oral and dermal toxicity.

For acute inhalative toxicity no adequate test data is available to decide on classification and labelling. A low inhalation hazard can be assumed based on the inhalation risk test performed (No mortality when exposed to the volatile components at 20 °C for 8 hours).

 

Acute/longterm, local

The test substance is not classified and labelled as irritating to eyes and skin based on test results with the read across substance Pigment Yellow 53. Furthermore it is not considered as sensitising based on a Buehler assay and a GPMT assay in guinea pigs.

 

Long term, systemic DNEL

Occupational exposure to the test substance occurs mainly by dermal route, and may also occur by inhalation exposure. Therefore two long-term DNELs are calculated for workers. In view of the data used for evaluation, the "dose-response factor" is considered to amount to a value of 1, and is thus not shown in the calculations presented below.

 

Exposure by inhalation

Pigment Green 50 includes 5-7% NiTiO3 as an impurity and has to be classified for Carc. 1A (inhalation), STOT RE 1 and Skin sens 1. According to the Scientific Committee an OEL of 0.005 mg/m3 (respirable fraction) is proposed for poorly soluble nickel compounds (SCOEL/SUM/85 June 2011). The impurity is insoluble in water and present as self-contained compound (not part of the spinel). Adapted to the content of NiTiO3 in Pigment Green 50 an OEL of 0.07 mg NiTiO3/m3 can be established which corresponds to 1 mg pigment/m3.

 

Dermal exposure

 

Step 1: Selection of the relevant dose descriptor (starting point):

In order to derive a long-term dermal DNEL, a dermal NOAEL was derived from NOAEL oral value (determined in a combined screening test with rats), as no repeated dose dermal study was available. The oral NOAEL of 1000 mg/kg bw/day was used as starting point.

 

Step 2: Modification into a correct starting point:

Correction for dermal absorption rates of the test substance (based on Guidance on information requirements and chemical safety assessment, R. 7C, 2014, Chapter R 7.12):

Dermal absorption is supposed to be low regarding the physico chemical properties of pigments. Pigments are considered as inert powders with very low water solubilities (ws <0.05 mg/L for Pigment Yellow 53). Additionally, no leaching of metal ions was detected in a leaching study with Pigment Green 50 (see IUCLID chapter 7.9.3).

Therefore, oral NOAEL of 1000 mg/kg bw/day was converted to a dermal NOAEL, considering a conservative 10 % absorption through the skin as owrst case assumption.

 In conclusion, dermal NO(A)EL = 1000 x (100/10) = 10000 mg/kg bw/d.

 

Step 3: Use of assessment factors: 300

Interspecies AF, allometric scaling (rat to human): 4

Interspecies AF, remaining differences: 2.5

Intraspecies AF (worker): 5

Exposure duration AF: 6

 

In conclusion, long term systemic dermal DNEL, workers = 33.3 mg/kg bw/day.

References

(not included as endpoint study record)

 

- ECHA (2012). Guidance on information requirements and chemical safety assessment. Chapter R.8: Characterisation of dose [concentration]-response for human health.

 

- ECHA (2014). Guidance on information requirements and chemical safety assessment. Chapter R.7.12: Endpoint specific guidance: Guidance on Toxicokinetics.

General Population - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

General Population - Hazard via oral route

Systemic effects

Long term exposure

Hazard assessment conclusion:

no hazard identified

Acute/short term exposure

Hazard assessment conclusion:

no hazard identified

DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:

no hazard identified