Ethylbenzenesulphonic acid

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Data is from peer reviewed journal

Justification for type of information:

Data is from peer reviewed journal

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Biodegradation study was conducted for 55 days for evaluating the percentage biodegradability of test substance Ethylbenzenesulphonic acid. Ultraviolet spectroscopic analysis was carried out for studying the biodegradation.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (IUPAC Name): Ethylbenzenesulphonic acid
- Common name: Ethyl benzene sulfonate
- Molecular formula : C8H10O3S
- Molecular weight : 186.23 g/mol
- Smiles notation : c1(ccc(CC)cc1)S(O)(=O)=O
- InChl : 1S/C8H10O3S/c1-2-7-3-5-8(6-4-7)12(9,10)11/h3-6H,2H2,1H3,(H,9,10,11)
- Substance type: Organic
- Physical state: Solid

Oxygen conditions:

not specified

Inoculum or test system:

other: Sewage

Duration of test (contact time):

55 d

Initial conc.:

5 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

other: UV

Details on study design:

TEST CONDITIONS
- Composition of medium: Synthetic medium was used as a test medium for the study. The composition of the test medium includes NH4Cl, K3HPO4, MgSO4, KCl, Yeast extract and deionised water, respectively.

TEST SYSTEM
- Culturing apparatus: Jar was used as a test vessel for the study.

CONTROL AND BLANK SYSTEM
- Inoculum blank: A control jar containing all ingredients except the sample, was prepared and inoculated in the same manner to serve as a reference medium for the UV analysis.

Key result

Parameter:

other: UV spectrophotomer

Value:

100

Sampling time:

6 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 100% degradation by UV spectrophotomer parameter after 6 days.

Table:Composition of Medium.

 

Compond	Wt.g
NH4Cl K3HPO4 MgSO4 KCl Yeast extract Deionised water	0.1500 0.0750 0.0125 0.0125 0.0050 1.0 liter

Table:Biodegradation of Aromatic Sulfonates in Synthetic medium--UV Analysis.

Sulfonate compound	Medium	Days of Incubation (percent remaining)
		1	2	3	4	5	6	10	15	20	25	30	35	45	55
Ethylbenzene	Synthetic	100		100	97	57	0

Validity criteria fulfilled:

not specified

Interpretation of results:

readily biodegradable

Conclusions:

The percentage degradation of test substance Ethylbenzenesulphonic acid in the synthetic medium system was determined to be 100% by UV spectrophotomer parameter after 6 days. Thus, based on percentage degradation, Ethylbenzenesulphonic acid is considered to be readily biodegradable in water.

Executive summary:

Biodegradation study was conducted for 55 days for evaluating the percentage biodegradability of test substance Ethylbenzenesulphonic acid (CAS no. 57352-34-8). Ultraviolet spectroscopic analysis was carried out for studying the biodegradation. Sewage was used as a test inoculums for the study.The sample under study were added to half-gallon fruit jars and diluted to 1 liter to give a 5 ppm (5 mg/l) concentration with the aqueous synthetic medium.Synthetic medium was used as a test medium. The composition of the test medium includes NH4Cl, K3HPO4, MgSO4, KCl, Yeast extract and deionised water, respectively.In the synthetic system each jar was inoculated with 5 ml of raw sewage. After mixing the contents, the lids were loosened and the samples allowed to incubate on a bench top at room temperature.A control jar containing all ingredients except the sample, was prepared and inoculated in the same manner to serve as a reference medium for the UV analysis. Aliquots were removed at intervals for the UV analyses which were made in 1 cm cells using the solution from the control jar as the reference solution in the spectrophotometer. The wave length region from 300 to 200 mµ was scanned at each sampling period, since these compounds exhibited two usable absorption peaks, one near 220 mµ and another generally near 270 mµ.The percentage degradation of test substance Ethylbenzenesulphonic acid in the synthetic medium system was determined to be 100% by UV spectrophotomer parameter after 6 days. Thus, based on percentage degradation, Ethylbenzenesulphonic acid is considered to be readily biodegradable in nature.

Description of key information

Biodegradation study was conducted for 55 days for evaluating the percentage biodegradability of test substance Ethylbenzenesulphonic acid (CAS no. 57352-34-8) (E. A. Setzkorn and R. L. Huddleston, 1965). Ultraviolet spectroscopic analysis was carried out for studying the biodegradation. Sewage was used as a test inoculums for the study.The sample under study were added to half-gallon fruit jars and diluted to 1 liter to give a 5 ppm (5 mg/l) concentration with the aqueous synthetic medium.Synthetic medium was used as a test medium. The composition of the test medium includes NH4Cl, K3HPO4, MgSO4, KCl, Yeast extract and deionised water, respectively.In the synthetic system each jar was inoculated with 5 ml of raw sewage. After mixing the contents, the lids were loosened and the samples allowed to incubate on a bench top at room temperature.A control jar containing all ingredients except the sample, was prepared and inoculated in the same manner to serve as a reference medium for the UV analysis. Aliquots were removed at intervals for the UV analyses which were made in 1 cm cells using the solution from the control jar as the reference solution in the spectrophotometer. The wave length region from 300 to 200 mµ was scanned at each sampling period, since these compounds exhibited two usable absorption peaks, one near 220 mµ and another generally near 270 mµ.The percentage degradation of test substance Ethylbenzenesulphonic acid in the synthetic medium system was determined to be 100% by UV spectrophotomer parameter after 6 days. Thus, based on percentage degradation, Ethylbenzenesulphonic acid is considered to be readily biodegradable in nature.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

Various experimental key and supporting studies for the target compound Ethylbenzenesulphonic acid (CAS No. 57352-34-8) were reviewed for the biodegradation end point which are summarized as below:

 

In an experimental key study from peer reviewed journal (E. A. Setzkorn and R. L. Huddleston, 1965), biodegradation experiment was conducted for 55 days for evaluating the percentage biodegradability of test substance Ethylbenzenesulphonic acid (CAS no. 57352-34-8). Ultraviolet spectroscopic analysis was carried out for studying the biodegradation. Sewage was used as a test inoculums for the study.The sample under study were added to half-gallon fruit jars and diluted to 1 liter to give a 5 ppm (5 mg/l) concentration with the aqueous synthetic medium.Synthetic medium was used as a test medium. The composition of the test medium includes NH4Cl, K3HPO4, MgSO4, KCl, Yeast extract and deionised water, respectively.In the synthetic system each jar was inoculated with 5 ml of raw sewage. After mixing the contents, the lids were loosened and the samples allowed to incubate on a bench top at room temperature.A control jar containing all ingredients except the sample, was prepared and inoculated in the same manner to serve as a reference medium for the UV analysis. Aliquots were removed at intervals for the UV analyses which were made in 1 cm cells using the solution from the control jar as the reference solution in the spectrophotometer. The wave length region from 300 to 200 mµ was scanned at each sampling period, since these compounds exhibited two usable absorption peaks, one near 220 mµ and another generally near 270 mµ.The percentage degradation of test substance Ethylbenzenesulphonic acid in the synthetic medium system was determined to be 100% by UV spectrophotomer parameter after 6 days. Thus, based on percentage degradation, Ethylbenzenesulphonic acid is considered to be readily biodegradable in nature.

 

Another supporting biodegradation study was conducted for evaluating the percentage biodegradability of test substanceEthylbenzenesulphonic acidby using cell suspensions of Pseudomonas testosterone H-8 (CAS no. 57352-34-8) (Marilyn J. Ripin, et. al; 1975).Pseudomonas testosteroniH-8 was used as a test inoculums obtained from American Type Culture Collection, Rockville, Md., as ATCC 27911. For larger quantities of cells, 10-liter cultures in mineral salts medium with benzene sulphonic acid (BS) (1 g/liter) as carbon source were grown in a 14-liter Microferm fermenter. The temperature was 30⁰C, with an impeller speed of 250 rpm and aeration at 4 liters/min. Cell free extract was prepared by using the following method. Washed cells grown on BS were suspended at about 0.1 g (wet weight)/ml in distilled water containing 2-mercaptoethanol (10-4 M, final concentration) and disrupted by 5 min of sonic oscillation. Cell debris was removed by centrifugation at 10,000 x g for 10 min in a Sorvall RC-2B refrigerated centrifuge, and the supernatant fluid was used as the crude extract (protein content, 3 mg/ml).. Warburg vessels received substrate (10 Mmol), extract (1.5 mg of protein), and pH 7.0 phosphate buffer (50 Amol) in a total volume of 2.8 ml (plus 0.2 ml of 40% KOH in center well). For the isolation of meta cleavage intermediate from the test chemicalEthylbenzenesulphonic acid, washed cells (3.3 mg, dry weight) were incubated with substrate (10 µmol) in 10 ml of pH 8.0 tris(hydroxymethyl) aminomethane hydrochloride buffer (0.003 M) at 30⁰ C until maximum development of yellow color. Cells were removed by centrifugation at 10,000 x g for 10 min (Sorvall RC-2B), and the supernatant fluid was extracted three times with 25-ml portions of diethyl ether. The ether extract was discarded and the aqueous layer was adjusted to pH 2.0 with HCl before extracting again with three portions (25 ml each) of diethyl ether. This ether extract was recovered and immediately shaken with 10 ml of pH. Formation of the yellow color products could be monitored spectrophotometrically during incubation of EBS with cell suspensions 7.6 tris(hydroxymethyl)aminomethane. The meta cleavage products from EBS was recovered by ether extraction of acidified reaction mixtures and the absorption spectra were compared and it was observed that the product accumulated in test inoculums was same as that for 4-methylcatechol.The percentage degradation of test substance Ethylbenzenesulphonic acid was determined to be 72% degradation by Spectrophotomer parameter. Thus, based on percentage degradation, Ethylbenzenesulphonic acid is considered to be readily biodegradable in water.

 

In an supporting study from peer reviewed journal (Marilyn J. Ripin, et. al; 1971), biodegradation experiment was conducted for evaluating the percentage biodegradability of test substanceEthylbenzenesulphonic acidby using cell suspensions of Pseudomonas testosterone H-8 (CAS no. 57352-34-8). A bacterium capable of extensive growth on BS was isolated from pond water and identified tentatively as P. testosteroneH-8. This culture was maintained on slants of mineral salts medium containing 1 g of BS per liter. The mineral salt medium was used as a test medium for the study. It consisted of the composition(per liter of distilled water): (NH4)2SO4, 1.0 g; MgSO4.7H20, 0.2 g; KH2PO4, 3.0 g; K2HPO4, 7.0 g; CaCl2, 10 mg; FeSO4-7H20, 5 mg; MnSO4, 2 mg; CuSO4, 50 µg; H3BO4, 10 µg; ZnSO4, 70 µg; and MoO3, 10 µg, respectively. Conical flasks with metal closures received 50 ml of medium per 250-ml flask or 200 ml per 1,000-ml flask and were incubated with rotary shaking (250 rev/min) at 30 C in a water bath (Metabolyte shaker). Growth was assessed by turbidity measurements at 600 nm with a Spectronic 20 spectrophotometer and correlated with dry weight by means of a previously constructed calibration curve. Conventional manometric techniques were used to measure respiration of twice-washed cell suspensions. Vessels received 6 to 10 mg (dry weight) of washed cells, 50 µmoles of phosphate buffer (pH 7.0), and various amounts of substrate in a volume of 2.8 ml. The center well received 0.2 ml of 20% KOH; oxygen consumption was measured at 30⁰C. Compounds were applied to Whatman no. 1 filter paper and developed by ascending or descending chromatography by using one of the following solvent systems: 1) I -butanol-acetic acid-water (8:2:2); 2) methylethylketoneethanol-ammonia (30:6:2); 3) 1-butanol saturated with ammonia and 4) 1-butanol-ethanol-water (4:1:5), respectively. Pinacryptol yellow (0.05% in water) spray was employed to locate arylsulfonates by fluorescence in ultraviolet light. Paper chromatography of test substance by using four solvent systems revealed single spots which gave a pink fluorescence with pinacryptol yellow. No growth occurred in control flasks of the mineral salts base alone without an added carbon source. Washed cells prepared from cultures of P. testosteroni H-8 grown in mineral salts medium with Benzene sulphonic acid (BS) as the carbon source were capable of rapid oxidation of test substance Ethylbenzenesulphonic acid. Thus, based on this, chemical Ethylbenzenesulphonic acid can be considered to be biodegradable in water.

 

On the basis of above results for target chemical Ethylbenzenesulphonic acid (from peer reviewed journals), it can be concluded that the test substance Ethylbenzenesulphonic acid can be expected to be readily biodegradable in nature.