5-nitrosalicylic acid

Endpoint summary

Additional information

Stability

Phototransformation in air :

The atmospheric oxidation half-life of 5-nitrosalicylic acid was estimated using the level III multimedia model. It was estimated that the substance is persistent in air medium as the half life period of 5-nitrosalicylic acid in air is 7.1 days. This indicates that 5-nitrosalicylic acid is not rapidly phototransformed in air.

Hydrolysis :

The Hydrolysis rate constant of 5-nitrosalicylic acid is estimated to be 0.0000000000197924 (19.7924 E-1 )cm3/molecule-sec. at half life of the 6.485 hrs.The estimated half life of the substance indicates that the substance is moderately hydrolysable.

Phototransformation in water

No experimental data available. As this study is not a standard information requirement in REACH and there is no indication from the CSA on the need to investigate further the fate and behaviour of the substance (Annex X requirement), no further testing is considered necessary.

Phototransformation in soil

No experimental data available. As this study is not a standard information requirement in REACH and there is no indication from the CSA on the need to investigate further the fate and behaviour of the substance (Annex X requirement), no further testing is considered necessary.

Biodegradation

Biodegradation in water :

No. of studies of target substance5-nitrosalicylic acidreviewed for Biodegradation in water: screening tests from reliable sources having Klimisch rating 2.

 

The summary of the results are presented below

 

 

Sr.No	Endpoint	Half life	Parameter	Sources
1	ready biodegradability	50% degradation in 15 days	Test mat. analysis	Predicted data from PBT profiler
2	ready biodegradability	51.66% degradation	O2 consumption	Predicted data from QSAR

 

 

By applying weight of evidence approach the target chemical found to be readily biodegradable with 50% to 51.66% percentage degradation.Thus it is concluded that 5-nitrosalicylic acid is biodegradable in water.

Biodegradation in water and sediment :

Based on the Level III Fugacity Model, the half life period of the 5-nitrosalicylic acid was estimated. The half period of 5-nitrosalicylic acid in water is 15 days (360 hrs) therefore it is considered that the substance will qualify as not persistent as the half life does not exceed the EPA criteria of 60 days. So, it can be confirmed that the substance is readily biodegradable in water medium where as in sediment the half life is 140 days (3360 hrs).

Based on this value, it can be inferred that the substance is persistent in sediment medium and is not readily biodegradable probably due to the anaerobic conditions existing in most sediments. However, it can be observed that 5-nitrosalicylic acid does not diffuse in the sediment medium since it's percentage in the sediment medium is reported to be 0% and hence persistence in the sediment compartment is not likely to be critical. 

Media	Half-Life (days)	Percent in Each Medium
Water	15	24%
Sediment	140	0%

Biodegradation in soil :

No. of studies of target substance5-nitrosalicylic acidreviewed for Biodegradation in soil from reliable sources having Klimisch rating 2.

 

The summary of the results are presented below

 

Sr.No	Endpoint	Half life	Parameter	result	Sources
1	ready biodegradability	30days	Test mat. analysis	biodegradable	Predicted data from PBT profiler and EPI suite
2	ready biodegradability	28.399 days	DT50(Dissipation time)	biodegradable	Predicted data from QSAR

 

 

By applying weight of evidence approach the target chemical found to be readily biodegradable with half life 28.399 to 30 days. does not exceeds the threshold (60 days) of being persistent in soil Thus it is concluded that 5-nitrosalicylic acid is biodegradable in soil.

Bioaccumulation

Bioaccumulation is the process by which the chemical concentration in an aquatic organism achieves a level that exceeds that in the water, as a result of chemical uptake through all possible routes of exposure. The relationship between bioaccumulation and bio-concentration is that, chemicals that have the potential to bioconcentrate also have the potential to bioaccumulate. Bioaccumulation is closely related to the Bioconcentration factor (BCF).

The estimated BCF of 5-nitrosalicylic acid in the key study was obtained to be 3.2. Supporting studies indicate the BCF to be between 1.0 to 30.1. This low value of BCF of 5-nitrosalicylic acid indicates its non bioaccumulative nature as the BCF factor is less than the bio-concentration threshold of 1000.

Transport and distribution

Adsorption / desorption :

Soil Adsorption Coefficient i.e Koc value of 5-nitrosalicylic acid was estimated as 549.3 L/kg by means of MCI method. This indicates that 5-nitrosalicylic acid will have a moderate tendency of sorption to soil and have slow migration potential to groundwater.The Koc value at 20 degC is equivalent to a value of 439.44.

Henry's Law constant :

Henry's Law states that at a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid. Henrys Law Constant of 5-nitrosalicylic acid at 25 deg C is 0.097 Pa m³/mol.