Disodium 4-hydroxynaphthalene-2,7-disulphonate

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

Data is from computational model developed by USEPA

Qualifier:

according to guideline

Guideline:

other: Modeling database

Principles of method if other than guideline:

KOCWIN Program (v2.00)

GLP compliance:

not specified

Type of method:

other: estimation

Media:

soil

Specific details on test material used for the study:

- Name of test material: Disodium 4-hydroxynaphthalene-2,7-disulphonate
- Common name: 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2)
- Molecular formula: C10H6Na2O7S2
- Molecular weight: 348.2624 g/mol
- Smiles notation: c1cc2c(cc1S(=O)(=O)[O-])cc(cc2O)S(=O)(=O)[O-].[Na+].[Na+]
- InChl: 1S/C10H8O7S2.2Na/c11-10-5-8(19(15,16)17)4-6-3-7(18(12,13)14)1-2-9(6)10;;/h1-5,11H,(H,12,13,14)(H,15,16,17);;/q;2*+1/p-2
- Substance type: Organic

Radiolabelling:

not specified

Test temperature:

25 deg C

Analytical monitoring:

not specified

Key result

Type:

Koc

Value:

954.5 L/kg

Temp.:

25 °C

Remarks on result:

other: log Koc= 2.9797 Estimated via MCI method

Transformation products:

not specified

KOCWIN Program (v2.00) Results:

==============================

SMILES : c12c(O)cc(S(=O)(=O)O([Na]))cc1cc(S(=O)(=O)O([Na]))cc2

CHEM : 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, disodium salt

MOL FOR: C10 H6 O7 S2 Na2

Koc may be sensitive to pH!

--------------------------- KOCWIN v2.00 Results ---------------------------

NOTE: METAL (Na, Li or K) HAS BEEN REMOVED TO ALLOW ESTIMATION via MCI!

Koc Estimate from MCI:

---------------------

First Order Molecular Connectivity Index ........... : 8.587

Non-Corrected Log Koc (0.5213 MCI + 0.60) .......... : 5.0764

Fragment Correction(s):

1 Sulfonic acid (-S(=O)-OH) ............. : -2.0000

1 Aromatic Hydroxy (aromatic-OH) ....... : -0.0966

Corrected Log Koc .................................. : 2.9798

Estimated Koc: 954.5 L/kg <===========

Validity criteria fulfilled:

not specified

Conclusions:

The Soil Adsorption Coefficient i.e Koc value of 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS No:20349-39-7) was estimated using EPI suite KOCWIN Program (v2.00) as 954.5 L/kg(log Koc= 2.9797) by means of MCI method at 25 deg.C. This Koc value indicates that the substance 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) has a moderate sorption to soil and sediment and therefore have slow migration potential to groundwater.

Executive summary:

The Soil Adsorption Coefficient i.e Koc value of 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS No:20349-39-7) was estimated using EPI suite KOCWIN Program (v2.00) as 954.5 L/kg(log Koc= 2.9797)  by means of MCI method at 25 deg.C. This Koc value indicates that the substance 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) has a moderate sorption to soil and sediment and therefore have slow migration potential to groundwater.

Description of key information

The Soil Adsorption Coefficient i.e Koc value of 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS No:20349-39-7) was estimated using EPI suite KOCWIN Program (v2.00) as 954.5 L/kg(log Koc= 2.9797)  by means of MCI method at 25 deg.C. This Koc value indicates that the substance 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) has a moderate sorption to soil and sediment and therefore have slow migration potential to groundwater.

Key value for chemical safety assessment

Koc at 20 °C:

945.5

Additional information

Predicted data studies have been conducted for target chemical 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS No:20349-39-7) for adsorption endpoint and their results are summarized below.

 

In first predicted data weight of evidence study the Soil Adsorption Coefficient i.e Koc value of 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS No:20349-39-7) was estimated using EPI suite KOCWIN Program (v2.00) as 954.5 L/kg(log Koc= 2.9797)  by means of MCI method at 25 deg.C. This Koc value indicates that the substance 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) has a moderate sorption to soil and sediment and therefore have slow migration potential to groundwater.

 

Another predicted data study 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 substance 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS no. 20349 -39 -7) was estimated to be 131 L/kg (log Koc = 2.1172) .The predicted KOC result based on the 5 OECD principles. Thus based on the result it is concluded that the test substance 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

 

By compiling both above mentioned studies it is concluded that test chemical 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) (CAS No:20349-39-7) can have log Koc value in range 2.1172 -2.9797, this value indicates that target chemical 2,7-Naphthalenedisulfonic acid, 4-hydroxy-, sodium salt (1:2) can have low to moderate sorption to and sediment and therefore have slow to moderate migration potential to ground water.

[LogKoc: 2.9797]