FINAL REPORT 

Study Title

DETERMINATION OF 'READY' BIODEGRADABILITY: CARBON 

DIOXIDE (CO2) EVOLUTION TEST (MODIFIED STURM TEST) OF 

1-PROPANESULFONIC ACID, 2-HYDROXY-3- 

(2-PROPEN-1-YLOXY)-, SODIUM SALT (1:1)

Author

M.J.E. Desmares-Koopmans, Bachelor, ERT

Test Facility

WIL Research Europe B.V.

Hambakenwetering 7

5231 DD ‘s-Hertogenbosch

The Netherlands

 

Laboratory Project Identification

Project 500675

Substance 204240/A

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1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) Project 500675

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1. CONTENTS

1. CONTENTS ...................................................................................................................................... 2

2. STATEMENT OF GLP COMPLIANCE............................................................................................. 3

3. QUALITY ASSURANCE STATEMENT ............................................................................................ 4

4. SUMMARY........................................................................................................................................ 5

5. INTRODUCTION .............................................................................................................................. 6

5.1. Preface...................................................................................................................................... 6

5.2. Aim of the study ........................................................................................................................ 6

5.3. Guidelines ................................................................................................................................. 6

5.4. Storage and retention of records and materials........................................................................ 6

5.5. Definitions.................................................................................................................................. 7

6. MATERIALS AND METHODS .......................................................................................................... 7

6.1. Test Substance ......................................................................................................................... 7

6.1.1. Test substance information............................................................................................. 7

6.1.2. Study specific test substance information ...................................................................... 7

6.1.3. Test concentration and preparation of test solutions...................................................... 8

6.2. Reference substance ................................................................................................................ 8

6.2.1. Reference substance...................................................................................................... 8

6.2.2. Reference substance concentration and preparation of test solutions........................... 8

6.3. Test system............................................................................................................................... 9

6.4. Test procedure and conditions.................................................................................................. 9

6.4.1. Preparation of bottles....................................................................................................10

6.4.2. Determination of CO2....................................................................................................10

6.4.3. Measurements and recording .......................................................................................11

6.5. Electronic data capture ...........................................................................................................11

6.6. Interpretation ...........................................................................................................................11

6.6.1. Data evaluation.............................................................................................................11

6.6.2. Acceptability of the test.................................................................................................12

6.7. List of deviations .....................................................................................................................12

6.7.1. List of protocol deviations .............................................................................................12

6.7.2. List of standard operating procedures deviations.........................................................12

7. RESULTS .......................................................................................................................................13

7.1. Theoretical CO2 production.....................................................................................................13

7.2. Biodegradation ........................................................................................................................13

7.3. Monitoring of temperature and pH ..........................................................................................14

8. CONCLUSION................................................................................................................................14

TABLES

Table 1 Calculation of the Carbon content. ................................................................................. 8

Table 2 pH values of different test media. .................................................................................14

Table 3 HCl titrated in duplicate blank bottles ...........................................................................15

Table 4 HCl titrated in Ba(OH)2 solution (background bottles)..................................................15

Table 5 CO2 production in the blank..........................................................................................16

Table 6 CO2 production and percentage biodegradation of the positive control substance......16

Table 7 CO2 production and percentage biodegradation of the test substance (bottle A). .......16

Table 8 CO2 production and percentage biodegradation of the test substance (bottle B). .......17

Table 9 CO2 production and percentage biodegradation of the toxicity control. .......................17

Table 10 Comparison of biodegradation of the test substance in bottles A and B......................17

FIGURES

Figure 1 Biodegradation of 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, 

sodium salt (1:1) and sodium acetate in the modified Sturm test.................................13

APPENDICES 

APPENDIX 1 TABLES ........................................................................................................................15

APPENDIX 2 CERTIFICATE OF ANALYSIS......................................................................................18

Final Report


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4. SUMMARY

Determination of ‘ready’ biodegradability: carbon dioxide (CO2) evolution test (modified Sturm test) 

with 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1).

The study procedures described in this report were based on the OECD guideline No. 301 B, 1992. In 

addition, the procedures were designed to meet the test methods of the Commission Regulation (EC) 

No. 440/2008 of 30 May 2008, Publication No. L142, Part C.4-C and ISO 9439, 1999.

1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was a clear colourless 

liquid and consisted of 3 components. The purity and composition were used for the calculation of the 

carbon content (14%). In the test a concentration of 86 mg/l was tested (172 mg in 2 Litres final 

medium), corresponding with 12 mg TOC/l. The Theoretical CO2 production (ThCO2) of 1-

Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was calculated to be 0.51 mg 

CO2/mg.

The study consisted of six bottles: 

- 2 inoculum blanks (no test substance), 

- 2 test bottles (1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1)), 

- 1 positive control (sodium acetate) and 

- 1 toxicity control (1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) plus 

sodium acetate).

Since 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was easily soluble in 

water the test media were prepared using a stock solution of 1 g/l in Milli-RO water. Aliquots of 172 ml 

of the clear and colourless stock solution were added to the test substance bottles A and B and to the 

toxicity control. These test bottles contained medium with microbial organisms (final volume: 2 litres). 

The test solutions were continuously stirred during the test, to ensure optimal contact between the test 

substance and the test organisms. Test duration was 28 days (last CO2-measurement on the 29th

day).

The relative biodegradation values calculated from the measurements performed during the test 

period revealed 8% and 21% biodegradation of 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-

yloxy)-, sodium salt (1:1), for the duplicate bottles tested. Thus, the criterion for ready biodegradability 

(at least 60% biodegradation within a 10-day window) was not met. 

In the toxicity control, 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was 

found not to inhibit microbial activity.

Since all criteria for acceptability of the test were met, this study was considered to be valid.

In conclusion, 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was 

designated as not readily biodegradable.

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5. INTRODUCTION

5.1. Preface

Sponsor Society of Chemical Manufacturers and Affiliates

1850 M Street, NW Suite 700

WASHINGTON, DC 20036

USA

Study Monitor Dr. C. T. Helmes

Test Facility WIL Research Europe B.V.

Hambakenwetering 7

5231 DD ‘s-Hertogenbosch

The Netherlands

Study Director M.J.E. Desmares-Koopmans, Bachelor, ERT

Study Plan Start : 23 January 2013

Completion : 02 May 2013

5.2. Aim of the study

The purpose of the study was to evaluate a non-volatile test substance for its ready biodegradability in 

an aerobic aqueous medium with microbial activity introduced by inoculation with the supernatant of 

activated sludge.

5.3. Guidelines

The study procedures described in this report were based on the Organization for Economic Cooperation and Development (OECD), OECD guidelines for Testing of Chemicals, Section 3, 

Degradation and Accumulation, guideline No. 301 B: "Ready Biodegradability: CO2 Evolution Test" 

adopted July 17, 1992.

In addition, the procedures were designed to meet the test methods prescribed by the following 

guidelines:

• Commission Regulation (EC) No. 440/2008 of 30 May 2008, Part C: Methods for the 

determination of ecotoxicity, Publication No. L142, C.4. "Biodegradation: determination of the 

'ready' biodegradability, C.4-C: Carbon dioxide (CO2) evolution test (Modified Sturm Test).

• ISO International Standard 9439 “Water Quality - Evaluation of ultimate aerobic 

biodegradability of organic compounds in aqueous medium - carbon dioxide evolution test 

(1999).

5.4. Storage and retention of records and materials

Records and materials pertaining to the study including protocol, raw data, specimens (except 

specimens requiring refrigeration or freezing) and the final report are retained in the WIL Research 

Europe archives for a period of at least 2 years after finalization of the report. After this period, the 

sponsor will be contacted to determine how the records and materials should be handled. WIL 

Research Europe will retain information concerning decisions made.

Those specimens requiring refrigeration or freezing will be retained by WIL Research Europe for as 

long as the quality of the specimens permits evaluation but no longer than three months after 

finalization of the report.

WIL Research Europe will retain a test substance sample until the expiry date, but no longer than 

10 years after finalization of the report. After this period the sample will be destroyed. 

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5.5. Definitions

Readily biodegradable are those test substances giving a result of at least 60% biodegradation 

within 28 days. This pass level must be reached within the 10 days immediately following the 

attainment of 10% biodegradation (10-day window).

Theoretical carbon dioxide (ThCO2) is the quantity of carbon dioxide calculated (mg) to be produced 

from the known or measured carbon content of the test substance when fully mineralized; also 

expressed as mg carbon dioxide evolved per mg test substance.

Total Organic Carbon (TOC) of a sample is the sum of the organic carbon in solution and in 

suspension.

6. MATERIALS AND METHODS

6.1. Test Substance

6.1.1. Test substance information

Identification 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-

yloxy)-, sodium salt (1:1)

Synonyms COPS_1 or CS-AHPS

Structure

O SO3

-

OH

Na+

Molecular formula C6H11NaO5S 

Molecular weight 218.22

Description Clear colourless liquid 

Batch 12E1101

Purity/Composition

 Sodium-1-allyloxy-2- 

 hydroxypropane sulphonate

 3-allyl-1,2-propanediol

 Water

CAS Number Percent

52556-42-0 38.64

123-34-2 2.26

7732-18-5 59.1

Test substance storage At room temperature in the dark

Stability under storage conditions Stable

Expiry date 13 August 2013

For the Certificate of Analysis see APPENDIX 2.

6.1.2. Study specific test substance information

Hygroscopic No

Volatile No

Stability in water 1 year

Solubility in water 1-45%

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6.1.3. Test concentration and preparation of test solutions

1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was a clear colourless 

liquid and consisted of 3 components. The purity and composition were used for the calculation of the 

carbon content (14%, see Table 1). In the test a concentration of 86 mg/l was tested (172 mg in 2 

Litres final medium), corresponding with 12 mg TOC/l.

Table 1 Calculation of the Carbon content.

Purity/Composition CAS Number Percent Molecular 

formula

Molecular 

weight % C

Sodium-1-allyloxy-2- 

hydroxypropane sulphonate

52556-42-0 38.64 C6H11NaO5S 218.22 33.0

3-allyl-1,2-propanediol 123-34-2 2.26 C6H12O3 132.16 54.5

Water 7732-18-5 59.1 H2O 19.02 0

Total 100 14.0

Since 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was easily soluble in 

water the test media were prepared using a stock solution of 1 g/l in Milli-RO water (tap water purified 

by reverse osmosis; Millipore Corp., Bedford, Mass., USA). A weighed amount of 1.0031 g of 

1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was dissolved in Milli-RO 

water and made up to 1000 ml. Aliquots of 172 ml of the clear and colourless stock solution were 

added to the test substance bottles A and B and to the toxicity control. These test bottles contained 

medium with microbial organisms (final volume: 2 litres). The test solutions were continuously stirred 

during the test, to ensure optimal contact between the test substance and the test organisms. 

6.2. Reference substance

6.2.1. Reference substance 

Identification number RS186

Name Sodium acetate

Description White powder (determined at WIL Research Europe)

Molecular formula CH3COONa (taken from label)

Molecular weight 82.03 (taken from label)

Batch number K34333668

Article number 1.06268.0250

Purity ≥99.0%

Expiry Date 28 February 2015

Certified Yes

Storage conditions At room temperature in the dark

Supplier Merck, Darmstadt, Germany

6.2.2. Reference substance concentration and preparation of test solutions

A solution of sodium acetate was prepared by dissolving 400.8 mg in Milli-RO water and making this 

up to a total volume of 100 ml. Volumes of 20 ml from this stock solution were added to 2 litres of the 

test medium of the positive control bottle and the toxicity control bottle, resulting in a final 

concentration of 40 mg sodium acetate per litre (12 mg TOC/l).

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6.3. Test system 

Source The source of test organisms was activated sludge freshly 

obtained from a municipal sewage treatment plant: 

'Waterschap Aa en Maas', Heeswijk-Dinther, The 

Netherlands, receiving predominantly domestic sewage.

Treatment The freshly obtained sludge was kept under continuous 

aeration until further treatment. The concentration of 

suspended solids was 3 g/l in the concentrated sludge 

(information obtained from the municipal sewage treatment 

plant [3.0 g/l] and confirmed by the determination of 

suspended solids [3.1 g/l]). Before use, the sludge was 

allowed to settle (34 minutes) and the supernatant liquid was 

used as inoculum at the amount of 15 ml/l1 of mineral 

medium. 

Reason for selection The test has been accepted internationally for determining 

the 'ready' biodegradability of test substances under aerobic 

conditions.

6.4. Test procedure and conditions

Test duration 28 days (last CO2-measurement on the 29th day).

During the test period the test media were aerated and 

stirred continuously.

Test vessels 2 litre all-glass brown coloured bottles.

Milli-RO / Milli-Q water Tap-water purified by reverse osmosis (Milli-RO) and 

subsequently passed over activated carbon and ionexchange cartridges (Milli-Q) (Millipore Corp., Bedford, 

Mass., USA). 

Stock solutions of A) 8.50 g KH2PO4

mineral components 21.75 g K2HPO4

67.20 g Na2HPO4.12H2O 

0.50 g NH4Cl

dissolved in Milli-Q water and made up to 1 litre, 

pH 7.4 ± 0.2

B) 22.50 g MgSO4.7H2O dissolved in Milli-Q water 

 and made up to 1 litre.

C) 36.40 g CaCl2.2H2O dissolved in Milli-Q water and

 made up to 1 litre.

D) 0.25 g FeCl3.6H2O dissolved in Milli-Q water and

 made up to 1 litre.

Mineral medium 1 litre mineral medium contains: 10 ml of solution (A), 

1 ml of solutions (B) to (D) and Milli-RO water.

Barium hydroxide 0.0125 M Ba(OH)2 (Boom, The Netherlands), stored in a 

sealed vessel to prevent absorption of CO2 from the air.

 

1 See also paragraph 6.7.1.

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Synthetic air (CO2 < 1 ppm) A mixture of oxygen (ca. 20%) and nitrogen (ca. 80%) was 

passed through a bottle, containing 0.5 - 1 litre 0.0125 M 

Ba(OH)2 solution to trap CO2 which might be present in small 

amounts. The synthetic air was sparged through the 

scrubbing solutions at a rate of approximately 1-2 bubbles 

per second (ca. 30-100 ml/min). 

6.4.1. Preparation of bottles

Pre-incubation medium The day before the start of the test (day -1) mineral 

components, Milli-RO water (ca. 80% total volume) and 

inoculum (1.5% final volume) were added to each bottle. 

This mixture was aerated with synthetic air overnight to 

purge the system of CO2. 

Type and number of bottles Test suspension: containing test substance

and inoculum (2 bottles).

Inoculum blank: containing only inoculum (2 bottles)

Positive control: containing reference substance and 

inoculum (1 bottle).

Toxicity control: containing test substance, reference 

substance and inoculum (1 bottle).

Preparation At the start of the test (day 0) test and reference substance 

were added to the bottles containing the microbial organisms 

and mineral components. 

 The volumes of suspensions were made up to 2 litres with 

Milli-RO water, resulting in the mineral medium described 

before.

Three CO2-absorbers (bottles filled with 100 ml 

0.0125 M Ba(OH)2) were connected in series to the exit air 

line of each test bottle.

6.4.2. Determination of CO2

Experimental CO2 production The CO2 produced in each test bottle reacted with the 

barium hydroxide in the gas scrubbing bottle and 

precipitated out as barium carbonate. The amount of CO2

produced was determined by titrating the remaining Ba(OH)2

with 0.05 M standardized HCl (1:20 dilution from 1 M HCl 

(Titrisol® ampoule), Merck, Darmstadt, Germany).

Measurements Titrations were made every second or third day during the 

first 10 days, and thereafter at least every fifth day until the 

28th day, for the inoculum blank and test suspension. 

Titrations for the positive and toxicity control were made over 

a period of at least 14 days.

Each time the CO2-absorber nearest to the test bottle was 

removed for titration; each of the remaining two absorbers 

was moved one position in the direction of the test bottle. A 

new CO2-absorber was placed at the far end of the series. 

Phenolphthalein (1% solution in ethanol, Merck) was used 

as pH-indicator.

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On the 28th day, the pH of all test suspensions was 

measured and 1 ml of concentrated HCl (37%, Merck) was 

added to the bottles of the inoculum blank and test 

suspension. The bottles were aerated overnight to drive off 

CO2 present in the test suspension. The final titration was 

made on day 29.

Theoretical CO2 production The theoretical CO2 production was calculated from the 

molecular formula.

6.4.3. Measurements and recording

pH At the start of the test (day 0) and on the 28th day.

Temperature of medium Continuously in a vessel with Milli-RO water in the same 

room.

6.5. Electronic data capture

Observations/measurements in the study were recorded electronically using the following programme: 

• REES Centron Environmental Monitoring system version SQL 2.0 (REES Scientific, Trenton, 

NJ, USA): Temperature.

6.6. Interpretation

6.6.1. Data evaluation

ThCO2, expressed as mg CO2/mg test substance, that can be generated by a test substance was 

calculated as follows:

Molecular substancetweight tes

carbonofNo. testinatoms substance Molecular weight CO2 ThCO2 × =

The first step in calculating the amount of CO2 produced is to correct for background (endogenous) 

CO2 production. Thus the amount of CO2 produced by a test substance is determined by the 

difference (in ml of titrant) between the experimental and blank Ba(OH)2 traps.

The amount of 0.05 N HCl titrated is converted into mg of CO2 produced:

ml1.144 HCl titrated

2

ml05.0 HCl titrated

mg CO2 ∆×=× ∆× =

Relative biodegradation values were calculated from the cumulative CO2 production relative to the 

total expected CO2 production based on the total carbon content of the amount of test substance 

present in the test bottles. A figure of more than 10% biodegradation was considered significant.

The relative biodegradation values were plotted versus time together with the relative biodegradation 

of the positive control. If applicable, the number of days is calculated from the attainment of 10% 

biodegradation until 60% biodegradation. Should this period be ≤ 10 days (10-day window), then the 

test substance is designated as readily biodegradable.

Toxicity control: if less than 25% biodegradation (based on ThCO2) occurred within 14 days, the test 

substance was assumed to be inhibitory.

The total CO2 evolution in the inoculum blank was determined by the cumulative difference (in ml of 

titrant) between the blank Ba(OH)2 traps and fresh Ba(OH)2. 

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6.6.2. Acceptability of the test

1. The positive control substance was biodegraded by at least 60% (71%) within 14 days. 

2. The difference of duplicate values for %-degradation of the test substance was always less than 

20.

3. The total CO2 release in the blank at the end of the test did not exceed 40 mg/l (62.7 mg CO2 per 

2 litres of medium, corresponding to 31.4 mg CO2/l).

4. The Inorganic Carbon content (IC) of the test substance (suspension) in the mineral medium at 

the beginning of the test was less than 5% of the Total Carbon content (TC). Since the test 

medium was prepared in tap-water purified by reverse osmosis (Milli-RO water (Millipore Corp., 

Bedford, Mass., USA, carbon levels < 500 ppb)), IC was less than 5% of TC (mainly coming from 

the test substance, 12 mg TOC/l).

Since all criteria for acceptability of the test were met, this study was considered to be valid.

6.7. List of deviations

6.7.1. List of protocol deviations

1. The concentration of suspended solids of the sludge as obtained from the municipal sewage 

treatment plant was at the lower limit of the range as described by the protocol (3.0 g/l). 

Therefore, the sludge will be allowed to settle and the liquid will be decanted for use as inoculum 

at the amount of 15 ml/l instead of 10 ml/l of mineral medium.

Evaluation: A logical correction on the amount of inoculum was made. Since all criteria for 

acceptability of the test were met, this deviation was considered to have no effect on the 

outcome of this study.

2. On day 1 temporary breakdown in the aeration (< 1 day) was noted in blank control A.

Evaluation: This relative short breakdown was considered to have no effect on the outcome of 

this study (the criterion for Ready biodegradability).

The study integrity was not adversely affected by the deviations.

6.7.2. List of standard operating procedures deviations

Any deviations from standard operating procedures were evaluated and filed in the study file. There 

were no deviations from standard operating procedures that affected the integrity of the study. 

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7. RESULTS

7.1. Theoretical CO2 production

The ThCO2 of 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was 

calculated to be 0.51 mg CO2/mg.

The ThCO2 of sodium acetate was calculated to be 1.07 mg CO2/mg.

The ThCO2 per test bottle are given in Tables 5-8 (APPENDIX 1). 

7.2. Biodegradation

All data are presented in APPENDIX 1. The results of CO2 production and biodegradation in blank 

bottles, background bottles and each test bottle are listed in Table 3 to 8. Table 10 contains the 

comparison of biodegradation of 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt 

(1:1) in bottles A and B. 

Figure 1 shows the curves for biodegradation of the two bottles with 1-Propanesulfonic acid, 2-

hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1), the positive control and the toxicity control.

Figure 1 Biodegradation of 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium 

salt (1:1) and sodium acetate in the modified Sturm test

The relative biodegradation values calculated from the measurements performed during the test 

period revealed 8% and 21% biodegradation of 1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-

yloxy)-, sodium salt (1:1), for the duplicate bottles tested. Thus, the criterion for ready biodegradability 

(at least 60% biodegradation within a 10-day window) was not met. 

In the toxicity control more than 25% biodegradation occurred within 14 days (33%, based on ThCO2). 

Therefore, the test substance was assumed not to inhibit microbial activity.

Functioning of the test system was checked by testing the reference substance sodium acetate, which 

showed a normal biodegradation curve (see also section 6.6.2).

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7.3. Monitoring of temperature and pH

The temperature recorded in a vessel with water in the same room varied between 22 and 23°C. 

The pH values of the different test media are presented in Table 2.

Table 2 pH values of different test media.

Test medium: At the start of the test: On day 28:

Blank control (A) 7.6 7.5

Blank control (B) 7.6 7.5

Positive control 7.6 7.8

1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, 

sodium salt (1:1) (A) 7.6 7.5

1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, 

sodium salt (1:1) (B) 7.6 7.5

Toxicity control 7.6 7.8

8. CONCLUSION

1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) was not readily 

biodegradable under the conditions of the modified Sturm test presently performed.

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APPENDIX 1 TABLES

Notes: Except for the percentages biodegradation, all calculations are performed without rounding off.

 Produced CO2 : negative values are expressed as 0.00 ml HCl.

Table 3 HCl titrated in duplicate blank bottles

Day HCl (0.05 N) titrated (ml)

Blank A Blank B Mean Value

2 47.16 47.11 47.14

5 45.28 46.20 45.74

7 46.04 46.53 46.29

9 47.23 46.93 47.08

14 46.33 46.20 46.27

19 45.91 46.00 45.96

23 45.02 45.40 45.21

27 45.29 45.05 45.17

29 44.80 44.90 44.85

29 49.11 49.58 49.35

29 50.16 50.10 50.13

Table 4 HCl titrated in Ba(OH)2 solution (background bottles)

Day HCl (0.05 N) titrated (ml)

Bottle A Bottle B Mean value

2 52.16 51.62 51.89

5 50.91 52.13 51.52

7 50.40 50.33 50.37

9 50.68 51.55 51.12

14 51.50 52.56 52.03

19 53.01 52.95 52.98

23 52.48 52.71 52.60

27 52.37 52.21 52.29

29 51.65 51.56 51.61

29 51.93 51.92 51.93

29 51.66 52.05 51.86

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APPENDIX 1 TABLES– CONTINUED

Table 5 CO2 production in the blank.

Day HCl (0.05 N) titrated (ml) Produced 

CO2

Produced 

CO2

Cumulative 

CO2

Ba(OH)2 

1) Blank (mean) (ml HCl) (mg) (mg)

2 51.89 47.14 4.76 5.2 5.2

5 51.52 45.74 5.78 6.4 11.6

7 50.37 46.29 4.08 4.5 16.1

9 51.12 47.08 4.04 4.4 20.5

14 52.03 46.27 5.77 6.3 26.9

19 52.98 45.96 7.03 7.7 34.6

23 52.60 45.21 7.39 8.1 42.7

27 52.29 45.17 7.12 7.8 50.5

29 51.61 44.85 6.76 7.4 58.0

29 51.93 49.35 2.58 2.8 60.8

29 51.86 50.13 1.73 1.9 62.7

1): "Strength" of untreated 0.0125 M Ba(OH)2 solution

Table 6 CO2 production and percentage biodegradation of the positive control substance.

Day

HCl (0.05 N) titrated (ml) Produced 

CO2

(ml HCl)

Produced 

CO2

(mg)

Cumulative 

CO2

(mg)

Biodegradation 1)

(%) Blank 

(mean)

Positive 

control

2 47.14 44.61 2.53 2.8 2.8 3

5 45.74 24.51 21.23 23.4 26.1 30

7 46.29 32.55 13.74 15.1 41.2 48

9 47.08 38.80 8.28 9.1 50.3 59

14 46.27 36.40 9.87 10.9 61.2 71

1): Calculated as the ratio between CO2 produced (cumulative) and the ThCO2 of sodium acetate: 85.8 mg CO2/2l

Table 7 CO2 production and percentage biodegradation of the test substance (bottle A).

Day HCl (0.05 N) titrated (ml) Produced 

CO2

Produced 

CO2

Cumulative 

CO2 Biodegradation 1)

(%) Blank (mean) Bottle A (ml HCl) (mg) (mg)

2 47.14 46.34 0.79 0.9 0.9 1

5 45.74 45.26 0.48 0.5 1.4 2

7 46.29 45.35 0.93 1.0 2.4 3

9 47.08 47.08 0.00 0.0 2.4 3

14 46.27 45.26 1.01 1.1 3.5 4

19 45.96 45.22 0.73 0.8 4.3 5

23 45.21 44.33 0.88 1.0 5.3 6

27 45.17 45.23 0.00 0.0 5.3 6

29 44.85 44.54 0.31 0.3 5.7 6

29 49.35 47.91 1.44 1.6 7.2 8

29 50.13 49.94 0.19 0.2 7.4 8

1): Calculated as the ratio between CO2 produced (cumulative) and the ThCO2 of the test substance: 88.0 mg CO2/2l

Final Report
1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) Project 500675

- Page 17 - 

APPENDIX 1 TABLES– CONTINUED

Table 8 CO2 production and percentage biodegradation of the test substance (bottle B).

Day

HCl (0.05 N) titrated (ml) Produced 

CO2

(ml HCl)

Produced 

CO2

(mg)

Cumulative 

CO2

(mg)

Biodegradation 1)

(%) Blank 

(mean) Bottle B

2 47.14 47.90 0.00 0.0 0.0 0

5 45.74 46.17 0.00 0.0 0.0 0

7 46.29 45.35 0.93 1.0 1.0 1

9 47.08 46.03 1.05 1.2 2.2 2

14 46.27 43.69 2.58 2.8 5.0 6

19 45.96 42.78 3.18 3.5 8.5 10

23 45.21 42.31 2.90 3.2 11.7 13

27 45.17 42.13 3.04 3.3 15.0 17

29 44.85 42.81 2.04 2.2 17.3 20

29 49.35 48.36 0.98 1.1 18.4 21

29 50.13 49.99 0.14 0.2 18.5 21

1): Calculated as the ratio between CO2 produced (cumulative) and the ThCO2 of the test substance: 88.0 mg CO2/2l

Table 9 CO2 production and percentage biodegradation of the toxicity control.

Day

HCl (0.05 N) titrated (ml) Produced 

CO2

(ml HCl)

Produced 

CO2

(mg)

Cumulative 

CO2

(mg)

Biodegradation 1)

(%) Blank 

(mean)

Toxicity 

control

2 47.14 45.61 1.53 1.7 1.7 1

5 45.74 28.06 17.68 19.4 21.1 12

7 46.29 32.96 13.33 14.7 35.8 21

9 47.08 38.51 8.57 9.4 45.2 26

14 46.27 34.93 11.34 12.5 57.7 33

1): Calculated as the ratio between CO2 produced (cumulative) and the sum of the ThCO2 of the test substance and 

 positive control: 173.8 mg CO2/2l (ThCO2 test substance: 88.0 mg CO2/2l + ThCO2 sodium acetate: 

 85.8 mg CO2/2l)

Table 10 Comparison of biodegradation of the test substance in bottles A and B.

Day Biodegradation (%)

Bottle A Bottle B Mean A and B ∆ A-B 1)

2 1 0 1 1

5 2 0 1 2

7 3 1 2 2

9 3 2 3 1

14 4 6 5 2

19 5 10 8 5

23 6 13 10 7

27 6 17 12 11

29 6 20 13 14

29 8 21 15 13

29 8 21 15 13

1): Absolute difference in biodegradation between bottles A and B

Final Report
1-Propanesulfonic acid, 2-hydroxy-3-(2-propen-1-yloxy)-, sodium salt (1:1) Project 500675

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APPENDIX 2 CERTIFICATE OF ANALYSIS

Final Report