Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability:

Phototransformation in air:-

The atmospheric oxidation half-life of 5 -nitro-o-anisidine was estimated using the level III multimedia model. It was estimated that the substance is not persistent in air medium as the half life period of 5 -nitro-o-anisisdine in air is only 1.8 days. This indicates that 5 -nitro-o-anisidine is rapidly phototransformable in air.

Hydrolysis:-

The Hydrolysis rate constant of 5 -nitro-o-aniside is estimated to be 0.0000000000089658 ( 8.9658 E-12 ) cm3/molecule-sec at half life of the 14.316h.The estimated half life of the substance indicates that the substance is moderately hydrolysable.

Biodegradation:-

Biodegradation in water:-

Based on QSAR prediction the percentage degradation of the compound 5-nitro-o-anisidine in water was estimated to be 87.6% in a duration of 28 days.

Also from the other weight of evidnece study it is found that the substance is 50% degradable in 38 days which does not exceed the EPA criteria of 60 days

Based on these half life values it is concluded that 5-nitro-o-anisidine is readily biodegradable (not persistent) in water.

No. of studies reviewed for biodegradation in water endpoints from reliable sources having Klimish rating 2

The summary of the results are presented below

Sr. No

Endpoint name

Value

Units

Half life

 1  % degradation  50  %  28 d
 2  % degradation  50  %  38 d

Based on the above information it can be concluded that the substance is readily biodegaradable and hence not persistent in water according to CLP regulation.

Biodegradation in water and sediment:

The half life period of 5 -nitro-o-anisidine in water is observed to be 912 h (38 days) while in sediment it is 8160 h (340 days). Based on these half life values of 5 -nitro-o-anisidine, it is concluded that the chemical is readily biodegradable in water where as it is non biodegradable in sediment. However, since there is no diffusion of the substance in the sediment as evident from the reported data (0% in sediment) and hence persistence in the sediment compartment is not likely to be critical.

Biodegradation in soil:

Based on QSAR prediction half life period of 5-nitro-o-anisidine in Soil was estimated to be 139 days.

Also from the other weight of evidnece study it is found that the substance is 50% degradable in 75 days which exceeds the EPA criteria of 60 days

Based on these half life values it is concluded that 5-nitro-o-anisidine is not readily biodegradable (persistent) in Soil.

No. of studies reviewed for biodegradation in water endpoints from reliable sources having Klimish rating 2.

Sr. No

Endpoint name

Value

Units

Half life

 1  % degradation  50  %  139d
 2  %degradation  50  %  75d

Based on the above information it can be concluded that the substance is not readily biodegaradable and hence persistent in Soil according to CLPregulation.

Bioaccumulation:-

Bioaccumulation: aquatic/ sediment

The estimated bioconcentration factor (BCF) for 5-nitro-o-anisidine by QSAR ,PBT profiler & EPI suit,HSDB,SciFinder,DEPA is 6.42 , 4.334, 2.7,11.7,4.16 respectively, which does not exceed the EPA bioconcentration criteria of 1000.

From this it is concluded that 5-nitro-o-anisidine is not expected to bioaccumulate in the food chain

No of studies reviewed for Bioaccumulation from reliable sources having Klimish rating 2,4

The summary of the results are presented below

Sr. No

Endpoint name

Value

 1  BCF  6.42
 2  BCF  4.334
 3  BCF  2.7
 4  BCF  11.7
 5  BCF  4.16

Based on the above valuesit can be concluded that the substance does not exceed the EPA bioconcentration criteria of 1000 and therefore is non bioaccumulative in nature according CLP regulation.

Transport and distribution

Adsorption/Desorption

Soil Adsorption Coefficient i.e Koc value of 5 -nitro-o-anisidine was estimated as 150(SRC). This indicates that the substance will negligiblely adsorb to the organic carbon fraction of the soil and will have a tendency to move with the water content in the soil. The key value of Koc of 150 (25°C) when converted at 20°C is equivalent to 120.

The supporting studies show values different from the key study which could be due to the difference in the estimation conditions. However for the purpose of the dossier and chemical safety assessment, the key study values shall be used.

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 -nitro-o-anisidine which is a solid at 25 °C is 0.000045 Pa m³/mol