Slags, phosphorus-manufg.

Endpoint summary

Additional information

For this endpoint 3 in vitro tests, performed according to OECD test guidelines, under GLP conditions, and QA, were selected as key studies:

 

- One Bacterial Reverse Mutation Assays (Ames test), performed according to OECD 471. Phosphorous slag did not induce a significant dose-related increase in the number of revertant (His+) colonies in each of the 4 Salmonella typhimurium test strains (TA1535, TA1537, TA98, and TA100) and in the number of revertant (Trp+) colonies in Escherichia coli test strain WP2uvrA, both in the absence and presence of S9-metabolic activation at concentrations of 100, 333, 1000, 3330, and 5000 µg/plate. These results were confirmed in an independently repeated experiment. It is concluded that Phosphorous slag is not mutagenic in the Ames test.

- An vitro Mammalian Chromosome Aberration Test, performed according to OECD 473 using cultured peripheral human lymphocytes. Phosphorous slag did not induce a statistically significant or biologically relevant increase in the number of cells with chromosome aberrations in the absence and presence of S9-mix, in either of the two independently repeated experiments, after various exposure times, at concentrations of 3, 10, and 33 ug/ml culture medium (highest possible concentration, at which some precipitation was observed). No effects of Phosphorous slag on the number of polyploid cells and cells with endoreduplicated chromosomes were observed both in the absence and presence of S9-mix. It is concluded that Phosphorous slag does not disturb mitotic processes and cell cycle progression and does not induce numerical chromosome aberrations. It is concluded that Phosphorous slag is not clastogenic in human lymphocytes in vitro.

- The ability of phosporous slag to induce mutations in the mouse lymphoma thymidine kinase locus was investigated in L5178Y cells in accordance with OECD 476 (in vitro Mammalian Cell Gene Mutation test). No significant increase in mutant colony numbers/mutation frequency was observed in both main experiments up to the maximum concentration with and without metabolic activation. Negative and positive controls were valid. This result was confirmed in an independent experiment with modifications in the duration of treatment time (-S9) and S9 concentration (+S9). Therefore, phosphorous slag is considered to be non-mutagenic in this mouse lymphoma assay.

 

No supporting studies were available.

 

Short description of key information:
- Gene mutation in bacteria (Bacterial Reverse Mutation Assay/Ames): not mutagenic (OECD 471, GLP).
- In vitro Mammalian Chromosome Aberration Test: non-clastogenic (OECD Guideline 473, GLP).
- In vitro Mammalian Cell Gene Mutation test: not mutagenic (OECD 476, GLP)

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

All in vitro key studies indicate that Phosphorous slag does not show any genotoxic potential. Therefore, it can be concluded that the substance is not mutagenic and therefore does not need to be classified for mutagenicity according to the criteria outlined in Annex I of 1272/2008/EC (CLP/EU-GHS) and Annex VI of 67/548/EEC.