2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs.

Endpoint summary

Additional information

Phototransformation in air :

The atmospheric oxidation half-life of 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. 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 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. in air is only 0.79 days. This indicates that 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. is easily phototransformed in air.

Hydrolysis :

The Hydrolysis rate constant of 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs is estimated to be 0.0000000000200865 cm3/molecule-sec. at half life of 6.39Hrs.The estimated half life of the substance indicates that the substance is moderately hydrolysable.

Biodegradation in water :

According to PBT Profiler, the half life period of 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. in water is 180 days and based on this value it can be concluded that the chemical is persistent in water medium and it will not bio-degrade easily.

Media	Half life (days)	Percent in medium
Water	180	2%

 

Biodegradation in water and sediment:

According to PBT Profiler , Half life period of 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs, in water is observed to be 4320hrs (180 days) while in sediment it is 38400hrs (1600 days). Based on these half life values it is concluded that the chemical 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs., is non biodegradable in both water as well sediment. Thesubstance will qualify as persistent as the half life exceeds the criteria of 40 and 120 days respectively for water and sediment respectively.

Media	Half life (days)	Percent in medium
Water	180	2%
Sediment	1600	28%

 

Biodegradation in soil:

 

The EPI Suite has estimated that 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. is expected to be found predominantly in soil and its persistence estimate is based on its availability in this medium. Half-life of 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. in soil was estimated to be 8640 hrs. (360 days) which exceeds the criteria of 120 days. Therefore, 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. is estimated to be persistent in the soil environment.

 

	Mass Amount (percent)	Half-Life (hr)	Emissions (kg/hr)
Soil	70.1	8.64e+003	1000

 

	Fugacity (atm)	Reaction (kg/hr)	Advection (kg/hr)	Reaction (percent)	Advection (percent)
Soil	1.69e-020	1.88e+003	0	62.7	0

 

 

Bioaccumulation : aquatic/ sediment :

Both the key study PBT Profiler and the supporting study EPI suite suggest that the estimated bioconcentration factor (BCF) for 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. is 10 , This value does not exceed the bioconcentration threshold of 2000. Thus, it is concluded that 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. is not expected to bioaccumulate in the food chain.

Adsorption / desorption :

The soil adsorption coefficient (Koc) of 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs is estimated to be 3680000 by MCI method.This Koc value is equivalent to 2944000 at 20°C. This value indicates that the substance will have very strong sorption to soil and sediment and negligible migration potential to groundwater.

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 2-Naphthalenol, 1-[[4-(phenylazo)phenyl]azo]-, ar',ar''-Me derivs. is estimated as is 0.00000005 Pa m³/mol at 25 deg C by bond contribution method.