Benzenesulfonic acid, 4-dodecyl-, cerium(4+) salt, basic

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, followed guideline with deviations

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

Deviations:

yes

Remarks:

(Test concentrations were not reported; results were based on the nominal concentrations rather than the measured concentrations)

GLP compliance:

not specified

Analytical monitoring:

not specified

Details on sampling:

Not reported

Vehicle:

not specified

Details on test solutions:

No information on the preparation of test solution were provided. The composition of C12-LAS tested in this study was 0.4% C10, 13.9% C11, 84.5% C12 and 1.2% C13. The molecular weight of C12-LAS was adjusted by subtracting the weight of sodium (i.e. 22.99) from the molecular weight of C12-NaLAS (i.e. 346.4) provided in Table 2 of the publication. Therefore, the molecular weight of C12-LAS was 323.41.

Test organisms (species):

other: Scenedesmus subspicatus (Desmodesmus subspicatus)

Details on test organisms:

Scenedesmus subspicatus (Desmodesmus subspicatus) ATCC N-11464 French strain (obtained from University of Metz)

Test type:

not specified

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

Not reported

Test temperature:

Not reported

pH:

Not reported

Dissolved oxygen:

Not reported

Salinity:

Not reported

Conductivity:

Not reported

Nominal and measured concentrations:

Not reported

Details on test conditions:

The test was conducted according to OECD guideline 201 and test medium recommended by AFNOR was used. The composition of the test medium was as follows:
i) 40 mg/L Ca(NO3)2.4H2O
ii) 100 mg/L KNO3
iii) 30 mg/L MgSO4.7H2O
iv) 40 mg/L K2HPO4
v) 0.015 mg/L CuSO4.5H2O
vi) 0.03 mg/L (NH4)6 Mo7O24.4H2O
vii) 0.03 mg/L ZnSO4.7H2O
viii) 0.03 mg/L CoCl2.6H2O
ix) 0.03 mg/L Mn(NO3)2.4H2O
x) 0.03 mg/L C6H5O7.H2O
xi) 0.03 mg/L BO3H3
xii) 0.8125 mg/L C6H5FeO7.5H2O
xiii) 0.3125 mg/L FeSO4.7H2O
xiv) 0.3125 mg/L FeCl3.6H2O
In the beginning, the cell concentration was adjusted to 10(4) cells/mL, using a Coulter Counter ZM. During the study, the culture flasks were shaken to facilitate the transfer of CO2.
Comparison of algal growth rates between the control and test groups were performed to derive the EC50 values. EC5 values were considered as NOEC since no noticeable variation was observed in the 0-5% interval.

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

48 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Details on results:

The 72-hr EC50 value of C12-LAS in Scenedesmus subspicatus (ATCC N-11464 French strain) was 48 mg/L. The 72-hr NOEC was 18 mg/L.

Table 1: Toxicity of pure LAS homologues using Scenedesmus subspicatus (ATCC N-11464 French strain)

 

Test substance	72-hr EC50 value (Std. deviation) (mg/L; based on growth rate)	72-hr NOEC (mg/L; based on growth rate)
Na-C10-LAS	270 (8.9)	80
Na-C11-LAS	111 (8)	40
Na-C12-LAS	48 (2.7)	18
Na-C13-LAS	30 (1.3)	12
Na-C14-LAS	18 (0.9)	7

 

Validity criteria fulfilled:

not specified

Conclusions:

Based on growth rate, the 72-hr EC50 and NOEC values of C12-LAS in Scenedesmus subspicatus (French strain) were 48 mg/L and 18 mg/L, respectively.

Executive summary:

The algal toxicity test of C12-linear alkylbenzene sulfonates (C12-LAS) was conducted in accordance with OECD guideline 201, using the test medium recommended by AFNOR.

 

Scenedesmus subspicatus ATCC N-11464 French strain obtained from University of Metz was used as the tester strains for this study. The composition of C12-LAS tested in this study was0.4% C10, 13.9% C11, 84.5% C12 and 1.2% C13. The molecular weight of C12-LAS was adjusted by subtracting the weight of sodium (i.e. 22.99) from the molecular weight of C12-NaLAS (i.e. 346.4) provided in Table 2 of the publication. Therefore, the molecular weight of C12-LAS was 323.41.

 

In the beginning, the cell concentration was adjusted to 10(4) cells/mL, using a Coulter Counter ZM. During the study, the culture flasks were shaken to facilitate the transfer of CO₂. Comparison of algal growth rates between the control and test groups were performed to derive the EC50 values. EC5 values were considered as NOEC since no noticeable variation was observed in the 0-5% interval.

 

Based on growth rate, the 72-hr EC50 and NOEC values of C12-LAS in Scenedesmus subspicatus (French strain) were 48 mg/L and 18 mg/L, respectively.

This toxicity study is classified as acceptable and satisfies the guideline requirements for the OECD 201 freshwater algae and cyanobacteria toxicity test.

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1982-08-06 To 1982-08-20

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Payne AG, Hall RH, 1979, in Aquatic Toxicology, ASTM, STP 667, pp. 171-180; and US EPA, 1978, The Selenastrum capricornutum Printz algal assay. Deviations, reliability, and validity evaluated using the subsequent OECD 201 (2006) test guideline.

Deviations:

no

GLP compliance:

no

Remarks:

(study conducted prior to GLP)

Specific details on test material used for the study:

Material was tested as 30.4% active (30.4% LAS, 51.9% water and 17.7% inert)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A primary stock solution of X0235.01 was prepared by adding a weighed amount of test material to algal growth medium, and other stock solutions were prepared by serial dilution. A growth medium control was conducted concurrently and contained no test material. All test concentrations were prepared by pipeting 1.0 milliliter (ml) of the appropriate stock solution to each test flask.
- Controls: AAP medium
- Evidence of undissolved material: No

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Green algae
- Strain: Not available
- Source: University of Texas at Austin, Austin, Texas
- Age of inoculum (at test initiation): Not available
- Method of cultivation: Not available

ACCLIMATION
- Acclimation period: Not available
- Culturing media and conditions: Same as test
- Any deformed or abnormal cells observed: Not available

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

120 h

Remarks on exposure duration:

72 hour results reported here

Post exposure observation period:

Yes (9 days)

Hardness:

Not available

Test temperature:

Static bioassays were conducted at 24 C (+/-1) degree C in water bath

pH:

Not available

Dissolved oxygen:

Not available

Nominal and measured concentrations:

Nominal laboratory exposure concentrations based on active ingredient were 0, 16, 32, 63, 125, 250, 500, and 1,000 mg/L.
No analytical measurements of test concentrations were taken.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Open / closed: Not available
- Material: 125-ml flasks with 50 ml solution
- Aeration: No
- Initial cells density: 2x10(4) cells/ml
- Control end cells density: Test 1: 206x10(4);
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

GROWTH MEDIUM
- Standard medium used: Yes, AAP nutrient medium

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: AAP media prepared with deionized water
- Total organic carbon: Not available
- Particulate matter: Not available
- Metals: Not available
- Pesticides: Not available
- Chlorine: Not available
- Alkalinity: Not available
- Ca/mg ratio: Not available
- Conductivity: Not available
- Culture medium different from test medium: No
- Intervals of water quality measurement: Not available

OTHER TEST CONDITIONS
- Sterile test conditions: Not available
- Adjustment of pH: No
- Photoperiod: Not available
- Light intensity and quality: Approximately 2,000 lux

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: Hemacytometer
- Cell counts were made on day 0,2,3,4,5.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2 - Range finding study: no

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

other: ECr50

Effect conc.:

235 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 72-hr ECr50: 235 (34.6 - 965) mg/L

Remarks:

Data is present within the study report to allow for 72 hr EC10 and EC50 endpoint calculations with the emphasis on growth rate (as recommended by OECD 201). The 72 hr modernized endpoints are reported within this summary.

Duration:

96 h

Dose descriptor:

other: ECr10

Effect conc.:

13.1 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 96-hr ECr10: 13.1 (0 - 99) mg/L

Remarks:

Data is present within the study report to allow for 72 hr EC10 and EC50 endpoint calculations with the emphasis on growth rate (as recommended by OECD 201). The 72 hr modernized endpoints are reported within this summary.

Details on results:

- Exponential growth in the control: Yes, 103X at 72 hrs
- Observation of abnormalities: In all test concentrations >=1.0 mg/L, the algal cells were abnormally large and malformed. Because of this observation, algae previously exposed to 1000 mg/L were tested for their ability to recover. Their growth was similar to the growth of the control during a 9-day recovery period in test material-free medium, and the algal cells had returned to normal appearance.
- Any stimulation of growth found in any treatment:
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No
- Effect concentrations exceeding solubility of substance in test medium: No

Effect of LAS on Selenastrum capricornutum: Cell Counts at 72 hr (study # 29101)

Nominal Conc (mg/L)	Algal cell counts (x10^4/ml)	Growth Rate	% Inhibition
0	318 (25)	1.5449
16	136 (37)	1.4586	5.59
32	138 (13)	1.2869	16.7
63	177 (34)	1.1447	25.91
125	45 (19)	0.8141	47.3
250	28 (4)	0.7504	51.43
500	24 (5)	0.7324	52.59
1000	5 (2)	0.3054	80.23

C10-13 LAS(X0235.01).

Numbers in parenthesis are standard deviation.

Validity criteria fulfilled:

yes

Conclusions:

In a 72 hour algae growth inhibition test, the EC10 and EC50 of LAS to Selenastrum capricornutum was 13.1 (0 – 99) and 235 (34.6 – 965) and mg/L, consecutively.

Executive summary:

In a 72 hour algal growth inhibition test, the green alga Selenastrum capricornutum was exposed to Linear Alkylbenzene Sulfonate (C11.9 LAS) in accordance with OECD 201. The nominal test concentrations were (test 1) control, 16, 32, 63, 125, 250, 500, and 1,000 mg a.i./L,.

The 72 hour EC10 and EC50, based on growth rate, are 13.1 (0–99) and 235 (34.6–965) mg/L, consecutively.

This algal growth inhibition test satisfies the guideline requirements of the OECD 201 guideline.

 

This study was conducted in accordance with USEPA OPPTS 850.5400. However data is present within the study report to allow for 72 hr EC10 and EC50 endpoint calculations with the emphasis on growth rate (as recommended by OECD 201). The 72 hr modernized endpoints are reported within this summary. These endpoints appear less conservative to those previously reported (96 hr endpoints based on cell count) due to the use of continuous growth rate versus cell count.

Reference 3

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 Dec 2013 - 11 Mar 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study performed according to OECD and/or EC guidelines and according to GLP principles. The observed adverse effect was considered to be due to phosphate deprivation (complexation with cerium and precipitation out of test solution). Phosphate measurements were conducted during the test to investigate this effect of complexation. Because this effect was specifically addressed in the test procedure and can not be relieved (e.g., additional phosphate additions would in their turn result in removal of all cerium from solution, consequently, the algae would not be exposed to the toxicant), there is no reason to reduce the reliability score.

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

the phosphate concentration in the test media was analysed, in order to assess potential phosphate depletion.

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: concentrations were determined in at least one of the triplicate samples from each treatment per sampling time.
- Sampling method: triplicate samples were taken from the test media of all test concentrations at the start of the test and at the end of the test (after filtration through a membrane filter, Whatman, Type NC45, pore size 0.45 µm). At the same sampling times, triplicate samples were also taken from the control. For the 72-hour stability samples, additional flasks containing the test medium with algae were incubated for each treatment under the test conditions.
- Sample storage conditions before analysis: room temperature in the dark after sampling until analysis

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Method: Due to the low solubility of the test item in the test media, a dispersion with the loading rate of 153 mg/L (corresponding to 100 mg/L anhydrous cerium trichloride) was sonicated for 15 minutes and continuously stirred at room temperature in the dark over 3 hours. The pH was adjusted to 6.5 and the dispersion was filtered. The dilutions 1:10, 1:22, 1:46, 1:100 and 1:220 of the undiluted filtrate with the loading rate of 100 mg/L anhydrous cerium trichloride were used as test media. Additionally, a control was tested in parallel.

No auxiliary solvent or emulsifier was used.

The stirring period of 3 hours was chosen according to the results of a pre-experiment, which showed that the solution equilibrium was reached after this time. In this pre-experiment similar test item concentrations were analytically determined in filtrates after stirring for 3, 24 and 96 hours.

At the end of the 3-hour stirring period, the pH of the dispersion was adjusted from 6.2 to 6.5 using 1 M NaOH solution. Afterwards, the dispersion of the test item was filtered through a membrane filter (Schleicher & Schuell, Type NC45, pore size 0.45 µm).

The undiluted filtrate was used as a stock solution for the preparation of the test media of lower test item concentrations. For this preparation, the filtrate was diluted with test water (pH adjusted to 6.5 using 1 M HCl). The test media were prepared just before the start of the test (= start of exposure).

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Strain: No 61.81 SAG
- Source (laboratory, culture collection): Collection of Algal Cultures (SAG, Institute for Plant Physiology, University of Göttingen, 37073 Göttingen / Germany).
- Age of inoculum (at test initiation): 4 days (preculture set up 4 days before the start of testing, and diluted 3-fold one day before the start of testing to assure that the algae were in the exponential phase.

ACCLIMATION
- Culturing media and conditions (same as test or not): same as test
- Any deformed or abnormal cells observed: no

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

15 mg/L CaCO3

Test temperature:

23-24°C

pH:

0 h: 6.6-7.1
24 h: 6.6-7.7
48 h: 7.3-8.6
72 h: 7.5-10.2
pH increase was the largest in the control and the treatments where algal growth was not or only minimally affected.

Dissolved oxygen:

not applicable

Salinity:

not applicable

Nominal and measured concentrations:

Test concentrations were: control, dilutions of 1:220, 1:100, 1:46, 1:22, and 1:10 of a filtered solution with nominal loading rate of 100 mg anhydrous CeCl3/L.
Dissolved Ce concentrations were as follows:
- 0 h (start of testing): < LOQ, 0.194, 0.451, 0.925, 1.97 and 4.39 mg Ce/L
- 72 h (end of testing): < LOQ, 0.0017, < LOQ, 0.022, 0.724 and 2.90 mg Ce/L

Over the test duration of 72 h, the concentrations of dissolved Ce decreased (recovery 0.1 to 66% of initially measured concentrations).
Due to the effect of phosphate depletion (see further, when phosphate is in excess of dissolved Ce, all Ce will be precipitated, when dissolved Ce is in excess of phosphate, all phosphate will be precipitated), it was decided to relate the effect concentrations to the initially measured concentrations of dissolved Ce.

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 50 mL containing 15 mL test solution
- Aeration: continuous stirring by magnetic stirrers
- Initial cells density: 5000 cells/mL

GROWTH MEDIUM
- Standard medium used: yes (reconstituted test water, AAP medium)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted test water (AAP Medium) prepared according to the test guidelines. Analytical grade salts were dissolved in sterile purified water
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: The solution with nominal loading rate of 100 mg/L anhydrous CeCl3 was adjusted to pH 6.5 using 1M NaOH solution after stirring and before filtration. The dilutions of the filtrate were diluted using test medium adjusted to pH 6.5 using 1M HCl solution.
- Photoperiod: continuous light
- Light intensity and quality: 7400 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: electronic particle counter (Coulter Counter, Model Z2).

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.1
- Range finding study: yes, control + undiluted filtrate (100 mg/L anhydrous CeCl3 as nominal loading rate) and dilutions of 1:10, 1:100 and 1:1000
- Results used to determine the conditions for the definitive study: No significant growth inhibition at 1:100 dilution, and 99.0% growth inhibition at 1:10 dilution.

Reference substance (positive control):

yes

Remarks:

potasssium dichromate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.63 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

dissolved

Remarks:

cerium

Basis for effect:

growth rate

Remarks on result:

other: 95% CL = 0.60-0.66

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.46 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

dissolved

Remarks:

cerium

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

1.1 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: cerium chloride, anhydrous

Basis for effect:

growth rate

Remarks on result:

other: 95% CL = 1.0-1.2

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.81 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: cerium chloride, anhydrous

Basis for effect:

growth rate

Details on results:

OTHER EFFECT PARAMETERS
Growth rate-based:
- 72-h LOEC = 0.94 mg Ce/L
- 72-h EC20 = 0.48 mg Ce/L
Yield-based:
- 72-h NOEC = 0.20 mg Ce/L
- 72-h LOEC = 0.46 mg Ce/L
- 72-h EC10 = 0.28 mg Ce/L
- 72-h EC20 = 0.35 mg Ce/L
- 72-h EC50 = 0.52 mg Ce/L

PHOSPHATE DEPLETION
- Phosphate content (mg/L) was measured at the start of testing as well as after 24, 48 and 72 h.
- Limit of quantification was 0.2 mg/L.
- Phosphate levels overall decreased with time due to algal growth in those treatments where no significant growth inhibition was observed.
- In the 1:100 dilution, some phosphate was detectable (but below the LOQ) at the start of testing but no phosphate was detected after 24, 48 and 72 h.
- In the 1:46 dilution and higher test item concentrations, no phosphate was detectable from the start of testing onwards. This suggests that the algal growth inhibition effect is concurrent with phosphate depletion and hence a phosphate deprivation effect rather than an effect of exposure to the dissolved rare earth.

OTHER OBSERVATIONS
- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no abnormalities observed
- Colour differences: no
- Any stimulation of growth found in any treatment: no
- Effect concentrations exceeding solubility of substance in test medium: no

Results with reference substance (positive control):

ErC50 (0-72h): 0.93 mg/L. The results were within the normal ranges.

Reported statistics and error estimates:

The EC10, EC20 and EC50 values and their 95% confidence intervals were calculated by Probit Analysis using linear maximum likelihood regression and linear weighted regression, respectively.
For determination of NOEC and LOEC average growth rate and yield at the test concentrations were compared to the control values by Williams t-test.

Analysis of phosphate:

At 0 hours, phosphate concentration decreased with increasing test concentration:

	Phosphate concentration (mg/L) at 0h	24h	48h	72h
control	0.4	0.3	< 0.2	< 0.2
1:220	0.3	0.2	< 0.2	< 0.2
1:100	0.1	< 0.2	< 0.2	< 0.2
1:46	< 0.2	< 0.2	< 0.2	< 0.2
1:22	< 0.2	< 0.2	< 0.2	< 0.2
1:10	< 0.2	< 0.2	< 0.2	< 0.2

The phosphate concentration in the test media was measured daily and was shown to decrease with higher concentrations of test item. This is thought to be due to the formation of complexes of the rare earth elements with the dissolved phosphate in the test water (which is a well-known behavior of rare earth elements in the environment). The amount of available phosphate also decreased over time, as it was metabolized by the algae.

Validity criteria fulfilled:

yes

Conclusions:

The effect of cerium trichloride on the growth of Pseudokirchnerella subcapitata has been investigated over a 72h period. The 72-hour NOEC based on growth rate was determined to be 0.46 mg Ce/L (corresponding to 0.81 mg CeCl3/L). The 72-hour EC50 based on growth rate was determined to be 0.63 mg Ce/L (corresponding to 1.1 mg CeCl3/L). Reduced growth rate was most probably due to phosphate depletion rather than due to primary toxicity of the test substance.

Executive summary:

The acute toxicity of cerium trichloride to algae was determined in a 72-hour static test according to the OECD guideline 201 and in compliance with the principles of Good Laboratory Practice.

At the end of the test, 0.1 to 66% of the initially measured concentrations of cerium were found. This is most likely due to the formation of complexes of cerium with the dissolved phosphate in the test water (which is a well-known behavior of rare earth elements in the aquatic environment). At the lowest test concentrations, phosphate was in excess of cerium and, therefore, almost all of the cerium precipitated, whereas phosphate was still measurable. At the higher concentrations, cerium was in excess and, consequently, higher dissolved cerium concentrations were measured, while the entire phosphate was depleted from the start. The 72-hour NOEC based on growth rate was determined to be 0.46 mg Ce/L (corresponding to 0.81 mg CeCl3/L). The 72-hour EC50 based on growth rate was determined to be 0.63 mg Ce/L (corresponding to 1.1 mg CeCl3/L). These reduced growth rates were most probably due to phosphate depletion rather than due to primary toxicity of the test substance.

Description of key information

Benzenesulfonic acid, 4-dodecyl-, cerium(4+) salt consists of a cerium cation and a benzenesulfonic acid  (4-C10-13-sec-alkyl derivate) anion. In the assessment of the toxicity of benzenesulfonic acid, 4-dodecyl-, cerium(4+) salt to algae, read-across to the assessment entities soluble cerium substances and benzenesulfonic acid (4-C10-13-sec-alkyl) anions is applied since the ions of benzenesulfonic acid, 4-dodecyl-, cerium(4+) salt determine its fate and toxicity in the environment.

Data of soluble cerium substances are available for the growth inhibition of freshwater algae Pseudokirchneriella subcapitata, yielding 72-h NOErC and ErC50 values of 0.63 mg Ce/L and 0.46 mg Ce/L.

Regarding the benzenesulfonic acid (4-C10-13-sec-alkyl) anion, a study comparable to OECD201 of Benzenesulfonic acid, C10-13-alkyl derivs., sodium salts on Raphidocelis subcapitata (formerly known as Selenastrum capricornutum) yielded 72-h EC10 and EC50 values of 13.1 and 235 mg/L, respectively. An additional study according to OECD201 of the representative substance sodium dodecylbenzensulphonate (CAS# 25155-30-0) on Scenedesmus subspicatus (Desmodesmus subspicatus) resulted in a 72-h EC50 and a NOEC of 48 mg/L and 18 mg/L, respectively. Thus, benzenesulfonic acid, 4-dodecyl-, cerium(4+) salt appears to have some toxicity to aquatic algae and cyanobacteria based on the toxicity of its dissociation products.