Sulfite liquors and Cooking liquors, green

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Migrated from Short description of key information:

Skin sensitisation studies are not available for green liquor. Therefore assessment of this endpoint shall comprise an assessment of the available other information, human, animal and alternative data of the known constituents of GL.  All constituents of green liquor have been used extensively for many decades by the industry and by consumers. However, apart from skin irritation or burns skin sensitization has normally not been described as secondary effects. Most GL constituents are ions, which are naturally present in the body and for this reason it is unlikely that they were strong skin sensitizers. Some information exists that Na2S has skin sensitizing properties (Deralenko and Hollinger, 2002), even if it has a harmonized classification for corrosivity only. Based on the data available, it is concluded that GL is not currently classifiable as a skin sensitiser, but potential for skin sensitisation effect cannot be completely ruled out.

Respiratory sensitisation

Endpoint conclusion

Additional information:

Migrated from Short description of key information:

All constituents of green liquor have been used extensively for many decades by the industry and by consumers. Long-lasting respiratory exposure for sulfides and sulfites may enhance symptoms of asthma in sensitive individuals. However, these human case reports are inplausible and NOAEL or LOAEL values cannot be evaluated. Based on the data available, it can be concluded that respiratory sensitisation of green liquor cannot be excluded.

Justification for classification or non-classification

According to CLP regulation, substances shall be classified as respiratory sensitisers (Category 1) in accordance with the following criteria: (a) if there is evidence in humans that the substance can lead to specific respiratory hypersensitivity and/or (b) if there are positive results from an appropriate animal test.

 

Test results from animal studies for green liquor are not available. Instead, data is available on the known inorganic constituents (hydroxides, sulfides, sulfites, sulfates, carbonates). Irritating and corrosive effects have been reported for skin and pulmonary track for these inorganic ions. However, no allergic response in skin or hypersensitivity of the airways has been reported in such extent that would lead to classification.

 

When considering the human evidence, the evidence could be referred to a chemical structure related to substances known to cause respiratory hypersensitivity. Mixtures should be classified as a respiratory or skin sensitiser when at least one ingredient has been classified as a respiratory or skin sensitiser and is present at or above the appropriate generic concentration limit (as shown in Table 3.4.3 of the CLP). Evidence from analogous substances, can contribute to the procedure for classification.

 

Regarding GL none of the known > 0.1% constituent is classified as respiratory sensitiser in the CLP List of harmonised classification and labelling of hazardous substances. Trace < 0.1% constituents Cr(VI) and Ni(SO₄) are classified as sensitisers. The analysed concentrations of these metals in GL remain at 0.1 mg/l level (as Ni) which is 0,00001 %. Chromium was not detected in reference sample (see 1.2 Composition) (VTT 2010) and therefore highly sensitizing Cr(VI) is not an issue in GL. In addition if Cr were present in GL, the reducing conditions of GL would favor the Cr(III) oxidation state.    

 

Based on information available, it can be concluded that GL cannot be classified as skin or respiratory sensitising substance.