4-methoxy-N-phenyl-o-toluidine

Endpoint summary

Description of key information

Adsorption/desorption:

The Soil Adsorption Coefficient i.e. Koc value of test chemical 4-methoxy-2-methyl-N-phenylaniline (CAS No. 41317-15-1) was estimated using EPI suite KOCWIN Program (v2.00) as 866.3 L/kg (log Koc= 2.9377) by means of MCI method at 25 deg. C.  This log Koc value indicates that test chemical 4-methoxy-2-methyl-N-phenylaniline has moderate sorption to soil and therefore test chemical has slow migration potential to ground water.

Additional information

Adsorption/desorption:

Various predicted data for the target compound of 4-methoxy-2-methyl-N-phenylaniline (CAS No. 41317-15-1)and supporting weight of evidence study for its read across chemical were reviewed for the Adsorption end point and their results are summarized as below.

In first predicted data study the Soil Adsorption Coefficient i.e. Koc value of test chemical 4-methoxy-2-methyl-N-phenylaniline (CAS No. 41317-15-1) was estimated using Estimation Program Interface (EPI suite , 2017) KOCWIN Program (v2.00) as 866.3 L/kg (log Koc= 2.9377) by means of MCI method at 25 deg. C.  This log Koc value indicates that test chemical 4-methoxy-2-methyl-N-phenylaniline has moderate sorption to soil and therefore test chemical has slow migration potential to ground water.

 

In next predicted data study the Soil Adsorption Coefficient i.e Koc value of test substance 4-methoxy-2-methyl-N-phenylaniline (CAS no.41317 -15 -1) was estimated using Adsorption Coefficient module (v12.1.0.50374) program of (ACD (Advanced Chemistry Development)/I-Lab predictive module, 2017)as Koc 1641 dimensionless (log Koc= 3.2151) at pH range 6 -14. This log Koc value indicates that the test substance 4-methoxy-2-methyl-N-phenylanilinehas a moderate sorption to soil and therefore has slow migration potential to groundwater.

Another predicted data study was done by using Sci Finder database of American Chemical Society (ACS, 2017) in this study the soil adsorption co-efficient i.e., Koc value of test chemical 4-methoxy-2-methyl-N-phenylaniline was estimated to be 2620 dimensionless (log Koc = 3.4183) at pH range 5-10 at temperature 25 deg.c. this value suggests that this test chemical has strong sorption to soil.

 

Similarly another prediction was done by using Chemspider-ACD/Phy chem suite of Royal Society of Chemistry (RCS, 2017) in this study the soil adsorption co-efficient i.e., Koc value of test substance 4-methoxy-2-methyl-N-phenylaniline (CAS no. 41317 -15 -1) was estimated to be 2214.23 dimensionless (log Koc= 3.3452) at pH 5.5 and 2214.39 dimensionless (Log Koc= 3.3452) at pH 7.4 and temperature 25 deg.C These Koc values at different pH indicates that the chemical 4-methoxy-2-methyl-N-phenylaniline has moderate sorption to soil and sediments and therefore test chemical has slow migration potential to ground water.

 

Last predicted data study was done from CompTox Chemistry Dashboard using OPERA (OPEn (quantitative) structure-activity Relationship Application)  V1.02 model in which calculation based on PaDEL descriptors (calculate molecular descriptors and fingerprints of chemical)  the adsorption coefficient i.e KOC for test substance4-methoxy-2-methyl-N-phenylaniline(CAS no. 41317 -15 -1) was estimated to be 1510 L/kg (log Koc = 3.1789) .The predicted KOC result based on the 5 OECD principles. Thus based on the result it is concluded that the test substance4-methoxy-2-methyl-N-phenylanilinehas a moderate sorption to soil and sediment and therefore has slow migration potential to ground water.

 

Further to support the results of predicted data of target chemical experimental study have been conducted for structurally similar read across chemicals from UERL lab 2017 in this study the adsorption coefficient Koc in soil and in sewage sludge of read across chemical Ethyl 2-naphthyl ether (CAS No.93 -18 -5) was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The solutions of the read across substance and reference substances were prepared in appropriate solvents. The read across chemical solution was prepared by accurately weighing 4 mg of test item and diluted with ACN up to10ml. Thus, the read across solution concentration was 400 mg/l. The pH of read across substance was 6.23. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after read across sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k (Annex - 2). The linear regression parameter of the relationship log Koc vs. log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the read across substance was determined from its measured capacity factor. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared or chosen according to functionally similarity with the read across substance and calibration graph prepared. The reference substances were Xylene, Ethylbenzene, Toluene, Naphthalene, phenanthrene having Koc value ranging from 2.369 to 4.09 The Log Koc value was determined to be 3.490 ± 0.003at 25°C. This log Koc value indicates that the substance Ethyl 2-naphthyl ether has a strong sorption to soil and sediment and therefore has negligible to slow migration potential to ground water.

 

On the basis of above results for target chemical 4-methoxy-2-methyl-N-phenylaniline (CAS No. 41317-15-1)(from EPI suite, ACD labs, Sci Finder database, Comptox chemistry dashboard and Chemspider 2017) and for its read across chemical (From UERL lab) it can be concluded that the log Koc value of test chemical 4-methoxy-2-methyl-N-phenylaniline ranges from 2.9377 to 3.4183 indicating that the chemical 4-methoxy-2-methyl-N-phenylaniline (CAS No. 41317-15-1) has moderate to strong sorption to soil and sediment and therefore it has slow migration potential to ground water.