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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Adsorption / desorption:

The Soil Adsorption Coefficient i.e Koc value of 4-amino-3-methylbenzenesulfonic acid  was estimated using EPI suite  KOCWIN Program (v2.00) as Koc 10 L/kg (log Koc = 1)  by means of MCI method at 25 deg.C. This Koc value indicates that the substance 4-amino-3-methylbenzenesulfonic acid  has a Negligible sorption to soil and sediment and therefore have rapid migration potential to groundwater.

Additional information

Adsorption / desorption:

Three different studies from validated predicted databases and experimental study for adsorption endpoint of target chemical 4-amino-3-methylbenzenesulfonic acid (Cas no. 98-33-9) with relevant read across which is structurally similar to target chemical are summarized as followed:

 

First study from prediction report using EPI suite KOCWIN model (v2.00) indicate the Soil Adsorption Coefficient i.e Koc value of 4-amino-3-methylbenzenesulfonic acid was estimated as Koc 10 L/kg (log Koc = 1) by means of MCI method at 25 deg.C. This Koc value indicates that the substance 4-amino-3-methylbenzenesulfonic acid has negligible sorption to soil and sediment and therefore have rapid migration potential to groundwater.

 

Whereas Chemspider - ACD/PhysChem Suite prediction model and Scifinder database indicate the soil adsorption coefficient i.e Koc value of test substance 44-amino-3-methylbenzenesulfonic acid was estimated to be 1 (Log koc-0) at pH 1-10 (including pH range 5.5 and 7.4 from Chemspider data source)and temperature 25 deg.C. This Koc value at all range of pH condition indicates that the substance 4-amino-3-methylbenzenesulfonic acid has negligible sorption to soil and sediment and therefore have rapid migration potential to groundwater.

 Above both predicted values of target chemical are further supported by experimental study of read across chemical 4-aminobenzenesulfonic acid (also reported as Sulfanilic acid; CAS no. 121-57-3) which suggest the adsorption coefficient (Koc) of substance Sulfanilic acid was found to be 10 using a structure estimation method based on molecular connectivity indices.This Koc value suggests that sulfanilic acid is expected to have very high mobility in soil.(HSDB database;2017)

All values for adsorption is in the range of log Koc 1-0 (L/kg or dimensionless) which gives common conclusion as target chemical 4-amino-3-methylbenzenesulfonic acid (Cas no. 98-33-9) has high mobility in soil/sediment compartment.