Calcium dodecylbenzenesulphonate

Endpoint summary

Additional information

Environmental fate and pathways

 

Environmental exposure

 

 

Calcium dodecylbenzenesulfonate is manufactured from linear alkylbenzene (LAB) in self-contained, enclosed systems. LAB is produced by reacting paraffins with benzene and a catalyst and isolating the LAB by distillation. The LAB is then sulfonated, which in turn is then neutralized to calcium salts of LAS.

In the Calcium dodecylbenzenesulfonate reaction process, the measured concentrations of SO2, NaOH were 0.0026 and 0.0356 mg/m3, which were below the occupational exposure limit of 0.2 mg/m3 and 2 mg/m3, respectively. And the dust are emitted to atmosphere but the concentration of the substances were below 10% level of environmental emission standard (10 mg/m3).

All occurred waste organic solvents are burned by waste consignment treatment. Wastewater is treated chemically and biologically, and then it is discharged to wastewater treatment plant. Most of the substance that is used in industrial and consumer products as surfactant and ingredient in detergents will be disposed of by the sewerage system. Exposure of the environment may occur mainly via effluents of STP’s and application of sewage sludge in agriculture.

 

Environmental fate

 

The environmental fate assessment for Calcium dodecylbenzenesulfonate (CaDDBS) is based on US EPA’s Estimation Programs Interface (EPI) Suite. EPI Suite provides estimations of physical/chemical properties and environmental fate properties.

Based on the output of the model, Calcium dodecylbenzenesulfonate (CaDDBS) is highly unlikely to bioaccumulate in the environment or aquatic organisms (i.e. fish).

 This also supports that the chemical is soluble in water such that it will exhibit mobility through the soil. In addition, the low log Koc (3.8864) further supports the expected soil mobility. The model-calculated linear and non-linear biodegradation probabilities suggest that the linear carbon chain will biodegrade rapidly, whereas the benzene ring is not expected to biodegrade as rapidly. The extremely low vapor pressure along with the short half life of approximately3.957hours indicates that if this chemical is present in the soil, it is not likely to be volatile and is expected to degrade rapidly.

The output parameters from the EPI Suite model support that any potential impacts of this chemical is expected to be very short-lived. This is because it is not likely to persist in water or microbial soils and sediments. As a result, the environmental fate of Calcium dodecylbenzenesulfonate (CaDDBS) is not likely to be of concern.

 

Hydrolysis will be not a significant factor in determining the environmental fate of Calcium dodecylbenzenesulfonate (CaDDBS).

Based on the results, dodecylbenzenesulfonic acid as a read across for Calcium dodecylbenzenesulfonate (CaDDBS) was hydrolytically stable (half life > 1 year) specified by the OECD Guidelines. Since the chemical is degradable less than 10% after 5 days in this test condition, it is presumably stable in water. (Hydrolytically stable).

 

 

Stability

 

Phototransformation in air

  

Using the AOPWIN QSAR model, the photochemical degradation rate of Calcium dodecylbenzenesulphonate in the atmosphere is 32.4364 E-12 cm3/molecule-sec, with a resultant predicted half live of 3.957 Hrs ( 0.330 Days (12-hr day; 1.5E6 OH/cm3))

  OVERALL OH Rate Constant = 32.4364 E-12 cm3/molecule-sec

  HALF-LIFE =    0.330 Days (12-hr day; 1.5E6 OH/cm3)

  HALF-LIFE =    3.957 Hrs

   

Calcium dodecylbenzenesulphonate has low vapor pressure (5.57E-019at 25C) indicating significant amounts of Calcium dodecylbenzenesulphonate are unlikely to be present in the atmosphere for photodegradation.

The estimated half-life is about 3.957 hours (32.4364 E-12 cm3/molecule-sec) with the AOPWIN (US EPA, 2011).

If released to air, a vapor pressure of 4.18E-021 mm Hg at 25 deg C (4.18E-021 mm Hg   is equivalent to vapour pressure of 5.57E-019 Pa) indicates significant amounts of Calcium dodecylbenzenesulphonate are unlikely to be present in the atmosphere for photodegradation and therefore Calcium dodecylbenzenesulphonate is not expected to be susceptible to direct photolysis by sunlight.

 

 

     

Phototransformation in water

 

After 30 minutes the Sodium dodecylbenzenesulfonate (DBS) have been decomposed and removal of the DBS absorption is complete after 2 hours of the light exposure.Rapid photodegradation (within 2 hours of light exposure) .

Dodecylbenzene sulfonate is rapidly photodegraded in aqueous aerated TiO2 suspensions. The reaction involves fast decomposition of the aromatic ring followed by slower oxidation of the aliphatic chain.

Data are available on the photodegradation of Na-C12 LAS in water.

Sodium dodecylbenzenesulfonate (CAS# 25155-30-0 , EC Number; 246-680-4 ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number; 247-557-8) ) and read-across is valid.

 

The results are as follows:

Table   Photodegradations of Na-C12 LAS

Light source	Light spectrum	Test material	Result	References
Xe lamp	>330 nm	Sodium dodecylbenzenesulfonate	Rapid (<1-2 hours) decomposition	Hidakaet al., 1985
Mercury vapor lamp	200-350 nm	Sodium dodecylbenzenesulfonate	>95% photolytic degradation after 20 minutes	Matsuura and Smith, 1970
Mercury lamp	400-580 nm	Sodium dodecylbenzenesulfonate	The presence of humic substances delayed the photodegradation	Hermannet al., 1997

 

 

Phototransformation in soil

If released to soil, Calcium dodecylbenzenesulfonate is expected to have very high mobility based upon an estimated Koc of 7699 Volatilization from moist soil surfaces is not expected to be an important fate process.

Therefore testing for Phototransformation in soils does not need to be performed.

 

Hydrolysis

 

Hydrolysis is a chemical reaction during which molecules of water (H2O) are split into hydrogen cations (H+, conventionally referred to as protons) and hydroxide anions (OH−) in the process of a chemical mechanism).

The study of MOE 2008 was performed following “OECD Guidelines for Testing of Chemicals No. 111: Hydrolysis as function of pH. The preliminary test was performed at 50 ±5°C and pH 4, 7 and pH 9. The hydrolysis of the substance was less than 10% over the 5 days, so a definitive test was not performed. Based on these results, dodecylbenzenesulfonic acid was hydrolytically stable (half life > 1 year) specified by the OECD Guidelines . Dodecylbenzene sulfonic acids (CAS# 27176-87-0 , EC Number; 248-289-4) ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number;247-557-8) ) and the dissociated acid it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.

 Since the chemical is degradable less than 10% after 5 days in this test condition, it is presumably stable in water. (Hydrolytically stable)

 

 Biodegradation

 

Data of following studies are demonstrating rapid biodegradation under aerobic and anaerobic conditions. Temmink and Klapwijk (2004) conducted OECD 301F test and the result is that more than 60% of mineralisation was achieved.

Biodegradation at 10 ppm was measured 75% after 11 days and test temperature was maintained at 20 deg C for 17 days. The substance could be concluded as readily biodegradable within 28 days.

For dodecylbenzene sulfonic acid (Dodecylbenzene sulfonic acids (CAS# 27176-87-0 , EC Number; 248-289-4) ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number;247-557-8) ) and the dissociated acid it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.), the available study indicates 69% of the material mineralized after 28 days ,OECD 301B test (USEPA 1992).

 

Ward and Larson (1989) conducted a laboratory study and observed the biodegradation rate constant and half-life for C₁₂-LAS in sludge-amended soil. The biodegradation rate constant for C₁₂-LAS is 0.030 day^-1and half-life for C₁₂-LAS is 23.1 days. Scheunertet al., (1987) measured the biomineralization rate of dodecylbenzenesulfonate in soil/water suspension under anaerobic and aerobic conditions for 42 days. The results (40.6%¹⁴CO₂: aerobic, 51.9%¹⁴CO₂: anaerobic) showed that the substance was readily biodegradable by the micro-organisms present in soil.

 

Summary of Biodegradation

 

Type/ Method	Test material	Degradation	Duration	References
Aerobic/ OECD 301F	C12-LAS	> 60 % of mineralisation	28 days	Temmink and Klapwijk, 2004
Aerobic/ Other	Sodium dodecylbenzenesulfonate	75 %	11 days	Cook and Glodman, 1974
Aerobic/ OECD 301B	Dodecylbenzenesulfonic acid	69 % of mineralisation	28 days	USEPA 1992
Aerobic/ Other	C12-LAS	50%	23.1 days	Ward and Larson, 1989
Aerobic and Anaerobic/ Other	Dodecylbenzenesulfonate	40.6%^14CO2of mineralization (aerobic), 51.9%^14CO2of mineralization (anaerobic)	42 days	Scheunertet al., 1987

 

Dodecylbenzene sulfonic acids (CAS# 27176-87-0 , EC Number; 248-289-4) ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number;247-557-8) ) and the dissociated acid it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.

 

Sodium dodecylbenzenesulfonate (CAS# 25155-30-0 , EC Number; 246-680-4 ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number; 247-557-8) ) and read-across is valid.

    

 

Biodegradation in water:screening tests

Data of following studies are demonstrating rapid biodegradation of C12-LAS under aerobic conditions. Temmink and Klapwijk (2004) conducted OECD 301F test and the result is that more than 60% of mineralisation was achieved within 28 days.

Cook and Glodman, 1974 conducted Biodegradation of sodium dodecylbenzene sulfonate (DBS), at 10 ppm was measured 75% after 11 days and test temperature was maintained at 20 deg C for 17 days. The sodium dodecylbenzene sulfonate (DBS) could be conclued as readily degradable.

For dodecylbenzene sulfonic acid, the available study indicates 69% of the material mineralized after 28 days ,OECD 301B test (USEPA 1992).

  

Table     Summary of Biodegradation in water:screening tests

 

Type/ Method	Test material	Degradation	Duration	References
Aerobic/ OECD 301F	C12-LAS	> 60 % of mineralisation	28 days	Temmink and Klapwijk, 2004
Aerobic/ Other	Sodium dodecylbenzenesulfonate	75 %	11 days	Cook and Glodman, 1974
Aerobic/ OECD 301B	Dodecylbenzenesulfonic acid	69 % of mineralisation	28 days	USEPA 1992

 

 

Dodecylbenzene sulfonic acids (CAS# 27176-87-0 , EC Number; 248-289-4) ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number;247-557-8) ) and the dissociated acid it readily dissociates in water and release the dodecylbenzene sulfonic anion in solution.

 

Sodium dodecylbenzenesulfonate (CAS# 25155-30-0 , EC Number; 246-680-4 ) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number; 247-557-8) ) and read-across is valid.

  

Biodegradation in water and sediment: simulation tests

 

In the study of Federle TW and Itrich NR 1997, Linear alkylbenzene sulfonate (14C-ring C12LAS) was tested as model compounds in two sludges.

-        Within 8 h, 41−44% was evolved as 14CO2,

-        1−2% remained as parent,

-        24−33% was incorporated into biomass,

-        and 10−15% was present as intermediates, primarily sulfophenylcarboxylates.

 Primary and complete biodegradation were best described by a first-order model. First-order rate constants for LAS were 0.96−1.10 h-1 for primary loss and 0.50−0.53 h-1 for complete degradation. This approach provides an accurate and comprehensive kinetic picture of biodegradation under realistic conditions as well as information on the mechanism of biodegradation.

Biodegradation of Linear alkylbenzene sulfonate (14C-ring C12LAS), at 1mg/lwas measured>96% after6hoursand test temperature was maintained at 20 deg C.

 

In the study of Kubodera T, Muto T and Yamamoto T 1978 Dodecylbenzenesulfonate 14C (DBS-14C) was tested as model compound.

Biodegradation of Dodecylbenzenesulfonate 14C(DBS-14C)at76ppmwas measured>90% after90hoursand test temperature was maintained at 24deg C.

DBS decreased from 76.0 ppm to less than 0.6 ppm at 90h (Readily degradation).The biodegradation of DBS-14C has three periods of rapid adsorption period, acclimation period, and degradation process. 1-Tetralone, 1-indanone, 4-methyl-1-tetralone, naphthalene were the decomposition products

 

Biodegradation in soil

 

Ward and Larson (1989) conducted a laboratory study and observed the biodegradation rate constant and half-life for C₁₂-LAS in sludge-amended soil. The biodegradation rate constant for C₁₂-LAS is 0.030 day^-1and half-life for C₁₂-LAS is 23.1 days. Scheunertet al., (1987) measured the biomineralization rate of dodecylbenzenesulfonate in soil/water suspension under anaerobic and aerobic conditions for 42 days. The results (40.6%¹⁴CO₂: aerobic, 51.9%¹⁴CO₂: anaerobic) showed that the substance was readily biodegradable by the micro-organisms present in soil.

 

Table     Summary of Biodegradationin soil

 

Type/ Method	Test material	Degradation	Duration	References
Aerobic/ Other	C12-LAS	50%	23.1 days	Ward and Larson, 1989
Aerobic and Anaerobic/ Other	Dodecylbenzenesulfonate	40.6%^14CO2of mineralization (aerobic), 51.9%^14CO2of mineralization (anaerobic)	42 days	Scheunertet al., 1987

 

Transport and distribution

Adsorption / desorption

 

The log of the adsorption coefficient(KOC) of Calcium dodecylbenzenesulphonate was estimated to be log KOC = 3.8864 which is equal to a KOC value of 7699 using the KOCWIN v2.00 QSARmethod.

 

 

KOCWIN Program (v2.00) Results:

SMILES : CCCCCCCCCCCCc1ccc(S(=O)(=O)O[Ca]OS(=O)(=O)c2ccc(CCCCCCCCCCCC)cc2)cc1

CHEM : Benzenesulfonic acid, dodecyl-, calcium salt

MOL FOR: C36 H58 O6 S2 Ca1

MOL WT : 691.06

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

Koc Estimate from MCI:

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

First Order Molecular Connectivity Index ........... : 21.781

Non-Corrected Log Koc (0.5213 MCI + 0.60) .......... : 11.9543

Fragment Correction(s):

2 Miscellaneous S(=O) group .......... : -2.5960

Corrected Log Koc .................................. : 9.3583

Estimated Koc: 2.282e+009 L/kg <===========

Koc Estimate from Log Kow:

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

Log Kow (User entered ) ......................... : 4.77

Non-Corrected Log Koc (0.55313 logKow + 0.9251) .... : 3.5635

Fragment Correction(s):

2 Miscellaneous S(=O) group .......... : 0.3229

Corrected Log Koc .................................. : 3.8864

Estimated Koc: 7699 L/kg <=========

 

      

 Henry's Law constant

 

 The estimated Henrys Law Constant (25 deg C) measured by calculation from EPI SuiteTM v4.1, HENRYWIN v3.20 Program was 1.093E-010 atm-m3/mole ( (1.108E-005 Pa-m3/mole) , which is almost zero.

This is Exposure Assessment Tools and Models made from EPA (Environmental Protection Agency).

 

 

Distribution modelling.

 

Calcium dodecylbenzenesulphonate has no affinity to be in air and sediment. The direct emissions to soil and surface water are significant, therefore Calcium dodecylbenzenesulphonate will be almost exclusively be found in soil and surface water.

Mackay fugacity modelling (level 3) indicates that, taking into account degradation and using inflow parameters which are consistent with the known production tonnage of this substance in, fugacity coefficient indicates that environmental concentrations in water are predicted to be 8.09e-023 (atm), in air (atm) 2.1e-023 and soil 8.08e-022 (atm) and sediment to be  1.35e-022 (atm).

These are negligible low levels. This can be considered a worse case prediction as it assumes all product is emitted with no emission control systems used.

 

 

    

Other distribution data

 

 

These results suggest for Calcium dodecylbenzenesulphonate that direct and indirect exposure from distribution in media is unlikely.

Based on low vapor pressure and low estimated log Pow, expected to partition to water and soil. Not expected to partition to air, sediments or biota.

 

Therefore testing for distribution in media does not need to be performed.

 

The estimated STP Fugacity Model and Volatilization From Water were measured by calculation from EPI SuiteTM v4.1 Program.

This is Exposure Assessment Tools and Models made from EPA (Environmental Protection Agency) .

 

                                 Volatilization From Water

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

 

Chemical Name: Benzenesulfonic acid, dodecyl-, calcium salt

 

Molecular Weight   : 691.06 g/mole

Water Solubility   : 3.477E-011 ppm

Vapor Pressure     : 4.18E-021 mm Hg

Henry's Law Constant: 1.09E-010 atm-m3/mole (calculated from VP/WS)

 

                                        RIVER         LAKE   

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

Water Depth    (meters):      1                1         

Wind Velocity   (m/sec):      5                0.5       

Current Velocity (m/sec):    1                0.05      

 

     HALF-LIFE (hours) :  1.408E+007       1.536E+008

     HALF-LIFE (days ) :  5.867E+005       6.4E+006  

     HALF-LIFE (years) :  1606                   1.752E+004

 

 

STP Fugacity Model: Predicted Fate in a Wastewater Treatment Facility

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

  (using 10000 hr Bio P,A,S)

PROPERTIES OF: Benzenesulfonic acid, dodecyl-, calcium salt

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

Molecular weight (g/mol)                              691.06

Aqueous solubility (mg/l)                             3.477E-011

Vapour pressure (Pa)                                  5.57288E-019

               (atm)                                           5.5E-024

               (mm Hg)                                     4.18E-021

Henry 's law constant (Atm-m3/mol)           1.09313E-010

Air-water partition coefficient                      4.47058E-009

Octanol-water partition coefficient (Kow)   1.34896E+014

Log Kow                                                       14.13

Biomass to water partition coefficient           2.69793E+013

Temperature [deg C]                                   25

Biodeg rate constants (h^-1),half life in biomass (h) and in 2000 mg/L MLSS (h):

         -Primary tank       0.00    10000.00      10000.00

         -Aeration tank      0.00    10000.00      10000.00

         -Settling tank      0.00    10000.00      10000.00

 

                              STP Overall Chemical Mass Balance:

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

                                         g/h              mol/h         percent

 

Influent                         1.00E+001        1.4E-002       100.00

 

Primary sludge              5.99E+000        8.7E-003       59.89

Waste sludge                 3.34E+000        4.8E-003       33.36

Primary volatilization    1.10E-017        1.6E-020        0.00

Settling volatilization    2.44E-017        3.5E-020        0.00

Aeration off gas            6.01E-017        8.7E-020        0.00

 

Primary biodegradation  1.75E-002        2.5E-005        0.18

Settling biodegradation   4.26E-003        6.2E-006        0.04

Aeration biodegradation 5.61E-002        8.1E-005        0.56

 

Final water effluent        5.96E-001        8.6E-004        5.96

 

Total removal                 9.40E+000        1.4E-002       94.04

Total biodegradation       7.79E-002        1.1E-004        0.78