Tris(methylphenyl) phosphate

Endpoint summary

Additional information

Toxicity to soil macroorganisms except arthropods

 

Testing on soil macro-organisms except arthropods is waived as being scientifically unnecessary. There exists three K1 GLP Terrestrial studies on the structural analogue Phenol, isopropylated, phosphate (3:1) CAS No 68937-41-7 (EC No 273-066-3). All of these studies demonstrate no effects at the maximum concentration tested within the study. As such, no further testing for terrestrial organisms in proposed.

 

Toxicity to terrestrial arthropods

 

Testing onterrestrial arthropodsis waived as being scientifically unnecessary. There exists three K1 GLP Terrestrial studies on the structural analogue Phenol, isopropylated, phosphate (3:1) CAS No 68937-41-7 (EC No 273-066-3). All of these studies demonstrate no effects at the maximum concentration tested within the study. As such, no further testing for terrestrial organisms in proposed.

 

Toxicity to terrestrial plants

 

Acute

This study is read across to Phenol, isopropylated, phosphate (3:1); CAS No 68937-41-7; EC No 273-066-3.

The effects of Durad 310M, incorporated into soil at concentrations of 100, 10, 1 and 0 mg/kg, upon the germination (emergence) and growth of seedlings of wheat (Triticum aestivum), radish (Raphanus sativus)and mung bean (Phaseolus aureus) were determined over periods of 19, 18 and 19 days respectively, representing 14 days after at least 50% emergence of control seedlings.

 

The LC50 for emergence and EC50 for growth rate were both greater than the highest concentration tested, 100 mg/kg, in all species.

 

No phytotoxic effects were observed for any of the species tested.

 

Chronic

 

In accordance with column 2 of REACH Annex X, Long-term toxicity testing shall be proposed by the registrant if the results of the chemical safety assessment according to Annex I indicates the need to investigate further the effects of the substance and/or degradation products on terrestrial organisms. The choice of the appropriate test(s) depends on the outcome of the chemical safety assessment. Lack of toxicity within the short term plant study on an analogous material was demonstrated. Furthermore, in Section 5.6 - Additional information on environmental fate and behaviour, a 90-day study on the uptake of the substance in plants is presented. Here it is demonstrated that the substance is not taken up significantly by plants, and does not appear to cause adverse toxicity in this prolonged study, although exploration of this endpoint is not detailed. The above and the fact that risk recommendations are implemented to avoid exposure to the environment, it is proposed that a long term toxicity test in plants is not required.

 

Toxicity to soil microorganisms

 

This study is read across to Phenol, isopropylated, phosphate (3:1); CAS No 68937-41-7; EC No 273-066-3.

The long-term effects on nitrogen transformation activity of soil microorganisms were minimal at concentrations 10, 32, 100, and 318 mg/kg dry soil. There was an observed effect of the substance on nitrogen transformation activity of soil microorganisms at concentration level 1010 mg/kg dry soil. After 28 days of exposure, the mean nitrate concentration in soil treated at 10, 32, 100, 318, and 1010 mg/kg dry soil exhibited a -1%, 1%, 0%, 2%, and 23% reduction in nitrate formation, respectively, compared to the controls. The EC10 was calculated to be 582.7 mg/L using linear interpolation between concentrations 318 and 1010 mg/L. The EC25 and EC50 were estimated to be >1010 mg/L, the highest concentration tested.

 

Toxicity to birds

 

There is sufficient mammalian toxicology available on the substance to preclude the requirements to test for toxicity to birds. As such, this endpoint is waived on the grounds of animal welfare and sufficient information on toxicological properties being available to adequately assess the substance.

 

Conclusion:

 

On the basis of read across, the alkylated phosphates are not proposed to present a hazard to terrestrial organisms. As such, the substance is not proposed to offer significant hazards to the terrestrial environment. The environmental fate of the substance indicates fairly rapid removal. In addition, it is the intention that the substance is not intentionally released, given its high hazard nature to the aquatic environment.