Phosphorus

Endpoint summary

Additional information

A bacterial reverse mutation (Ames) study (Huntingdon Life Sciences, 2011) was conducted to assess the potential for Fe₃P to cause gene mutation. The study was conducted according to OECD test guideline 471, EC guideline method B13/14, and US EPA and Japanese guidelines, and in compliance with GLP.

Four mutant strains of Salmonella Typhimurium (TA1535, TA1537, TA98, and TA100) and one strain of Escherichia coli (WP2 uvrA) were treated with Fe₃P at a series of concentrations (5 µg/plate – 5000 µg/plate); the tests were run with and without metabolic activation (S9 mix).

No increase in the number of revertant colonies was seen relative to the concurrent vehicle controls in any of the strains tested at any concentration, either with or without metabolic activation.

It was concluded that Fe₃P, had showed no evidence of mutagenic activity in this bacterial system under the conditions employed.

 

A chromosomal aberration study (Huntingdon Life Sciences, 2011) was conducted to assess the cytogenetic potential of Fe₃P in human lymphocytes. The study was conducted according to OECD test guideline 473, EU guideline B10, and US EPA, Japanese, and ICH guidelines, and in compliance with GLP.

Human lymphocytes, in whole blood culture, were stimulated to divide by addition of phytohaemagglutinin, and exposed to the test substance both in the absence and presence of S9 mix derived from rat livers. Solvent and positive control cultures were also included. Two hours before the end of the incubation period, cell division was arrested using Colcemid®, the cells harvested and slides prepared, so that metaphase cells could be examined for chromosomal damage.

No statistically significant increase in the proportion of metaphase cells containing chromosomal aberrations when compared to the concurrent negative controls. It was concluded that Fe₃P had not shown any evidence of causing an increase in the frequency of structural chromosome aberrations in the in vitro cytogenetic test system, under the experimental conditions.

 

A mouse lymphoma assay (Huntingdon Life Sciences, 2011) was conducted to assess the mutagenic potential of Fe₃P. The study was conducted according to OECD guideline 476, EU guideline B17, and US EPA, Japanese, and ICH guidelines, and in compliance with GLP.

Mouse lymphoma L5178Y cells were treated with a suspension of Fe₃P at concentrations up to the typical limit dose of 10 mM (1985 µg/mL), with and without metabolic activation (S9 mix).

No increase in mean mutant frequencies were seen in any of the tests conducted, nor was any reduction in relative total growth (RTG) observed. It was concluded that Fe₃P had not shown any mutagenic potential in this in vitro cell mutation assay, under the experimental conditions described.

Short description of key information:
Ames: Negative with and without metabolic activation (S9 mix)
Chromosome aberration: no evidence of an increase in the frequency of structural chromosome aberrations.
Mouse Lymphoma Assay: no evidence of mutagenic activity with or without metabolic activation.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Three in-vitro studies (as described above) examined aspects of the mutagenic potential of Fe₃P. None of these studies indicated any mutagenic potential whatsoever. In conclusion, Fe₃P should be considered void of any genotoxic potential. Accordingly, it does not require classification as hazardous on the basis of mutagenic activity according to either the CLP Regulation (Regulation (EC) 1272/2008), or the Dangerous Substances Directive (Directive 67/548/EEC).