Registration Dossier

Ecotoxicological information

Long-term toxicity to fish

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
fish short-term toxicity test on embryo and sac-fry stages
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Nov. 27, 1986 To Feb. 6, 1987
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Qualifier:
no guideline available
Principles of method if other than guideline:
Fertilized eggs of Salmo gairdneri were exposed to concentrations of 0.03, 0.23, 0.35, 0.63, 0.95 and 1.9 mg/L (mean measured), for 70 days. The responses recorded included the survival of eggs, time to eyed egg stage, time to hatch, survival and final weight of sac-fry (eleutheroembryos), time and extent of swim-up (external feeding)
GLP compliance:
yes
Analytical monitoring:
yes
Details on sampling:
Representative test vessels were sampled six times during the study, and two days before introduction of eggs.
Details on test solutions:
A stock solution of 920 mg LAS/L was prepared every seven days. Test solutions were made by a mini-diluter system.
Test organisms (species):
Oncorhynchus mykiss (previous name: Salmo gairdneri)
Details on test organisms:

Eggs and sperm from Chirk trout hatchery, North Wales, were obtained from 6 individual, over 4 year old, rainbow trout and transported to the laboratory where the eggs were fertilized less than 4 hours after stripping. After swim-up, each fish was fed commercial trout feed at 8% body weight per day spread over 2-3 feedings.
Test type:
flow-through
Total exposure duration:
72 d
Post exposure observation period:
Exposure was continued until several days post-swim-up, 72 days post-fertilization. The responses recorded included the survival of eggs, time to eyed egg stage, time to hatch, survival and final weight of sac-fry (eleutheroembryos), time and extent of swim-up (external feeding).
Hardness:
70-133 mg/L CaCO3
Test temperature:
8.5-11.5 degree C
pH:
7.3-7.9
Dissolved oxygen:
8.8-10.3
Nominal and measured concentrations:
Nominally: 0, 0.2, 0.35, 0.62, 1.12 and 2.0 mg/L.
Mean measured concentrations: 0.03, 0.23, 0.35, 0.63, 0.95 and 1.9 mg/L.
Details on test conditions:
Fertilized eggs were exposed in a mini-diluter test system on stainless steel mesh beds in 0.5 L test vessels in two treatment groups. One group was exposured to LAS immediately post-fertilization and one group was exposured to LAS from the eyed-egg stage (19 days post-fertilization). This group was maintained in the test system and dosed with dilution water (carbon filtered tap water) prior to exposure to LAS. Each test vessel contained 30 eggs at the start of the test. Any dead life stages were removed daily.

LAS test solutions were dosed continuously at 25 mL/min, equivalent to approximately 15 volume replacements per day. There were 2 replicates for each treatment and 6 exposure concentrations.
Key result
Duration:
72 d
Dose descriptor:
NOEC
Effect conc.:
0.23 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
other: overall survival (fertilization to swim-up)
Details on results:
NOECs based on mean measured concentrations (mg/L) were:

time to eyed egg stage no effect at highest concentration
survival of eggs exposed from eyed stage 0.23
survival of eggs exposed from fertilization 0.23
time to hatch no effect at highest concentration
survival of sac-fry 0.23
overall survival (fertilization to swim-up) 0.23
final weight of sac-fry 0.35
time to swim-up eggs exposed from fertilization 0.35
time to swim-up exposed from eyed stage no effect at concentrations where fry survive
Conclusions:
The lowest NOEC for Salmo gairdneri over 72 days was 0.23 mg/L.
Executive summary:

Fertilized eggs of Salmo gairdneri were exposed to concentrations of 0.03, 0.23, 0.35, 0.63, 0.95 and 1.9 mg/L (mean measured), for 72 days. The responses recorded included the survival of eggs, time to eyed egg stage, time to hatch, survival and final weight of sac-fry (eleutheroembryos), time and extent of swim-up (external feeding). The lowest NOEC value found was 0.23 mg/L based on survival of eggs exposed from eyed stage, survival of eggs exposed from fertilization, survival of sac fry, and overall survival from fertilization to swim-up. The data are for C11.6 LAS and no normalization is required.

Endpoint:
fish life cycle toxicity
Type of information:
read-across based on grouping of substances (category approach)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
Refer to the section 13 of the dataset for details on the read across justification.
Qualifier:
equivalent or similar to
Guideline:
other: USEPA NWQL 1972 Recommended bioassay procedure for Fathead Minnow (Pimephales promelas) Rafinesque Chronic Tests
Version / remarks:
Conducted by the US Environmental Protection Agency using their internal guidance document prior to any accepted fish full life cycle guidance.

GLP compliance:
no
Analytical monitoring:
yes
Details on sampling:
Daily 25 mL samples were removed from each chamber, composited, preserved with formalin and kept under refrigeration until measured.
Details on test solutions:
Every 3 days, a stock solution of LAS was prepared in demineralized water. Aliquots were added automatically to the diluter that delivered four test concentrations and control water to the test chambers.
Test organisms (species):
Pimephales promelas
Details on test organisms:
Fish were obtained from the ponds at the Newtown Fish Farm, Ohio Division of Wildlife. The small young-of-the-year fish were collected in late September and held in cold water. During the last week of December, 25 fish were placed randomly into each exposure chamber where they were maintained in a continuous flow of dilution water similar to that used during the test. The four largest and eight smallest fish from each aquarium were selected in order to reduce the number of fish and to try to get a more equal distribution of sexes. The fish were fed with a commercial dry fish food daily. The exposure to LAS was started during the last week of February.

Test type:
flow-through
Water media type:
freshwater
Limit test:
no
Total exposure duration:
196 d
Hardness:
water hardness ranged from 194-214 mg/L CaCO3
Test temperature:
During the test, the weekly average temperature rose from 20 to 24 degree C. Maximum weekly fluctuation was 5 degree C. There was less than 1 degree C variation between exposure chambers at a given time.
pH:
pH ranged from 7.50-7.95
Dissolved oxygen:
Mean dissolved oxygen 5.84-6.42 mg/L
Nominal and measured concentrations:
Mean measured test concentrations were 0.34, 0.63, 1.2 and 2.7 mg/L.
Details on test conditions:
Two duplicate exposure systems consisted of five 10 gallon glass aquaria with slate bottoms. During the first four months a serial-dilution unit was used to maintain the LAS at the desired concentration in System I and a proportional dilution unit was used in System II, both to provide continuous exposures to fathead minnows. During the latter part of the test, the flows from a new proportional dilution unit were divided to supply both exposure systems and a fry exposure system.

The exposure to LAS was started during the last week of February. Pieces of half-tile were placed in each 10-gal aquarium for spawning sites. Spawning occurred from March 27 to September 7. Tiles were examined daily for eggs. After spawning had been completed, the cluster of eggs was removed and counted. Eggs cups consisted of nylon monofilament screen (38 mesh) on one end of a 7.6 cm long and 5.1 cm diameter plastic pipe. Eggs cups were suspended in the exposure chambers from an oscillating frame. Four replicates of 100 eggs from each concentration and the control were reared for 14 days in their respective exposure solutions and mortality of eggs and fry recorded daily.

Fish were weighed at the beginning of the test, after 5 weeks of exposure and at the end of the test in all concentrations and the control.

The test was conducted with a photoperiod of 16 h light:8 h dark.

Reference substance (positive control):
not specified
Key result
Duration:
14 d
Dose descriptor:
NOEC
Effect conc.:
0.96 mg/L
Basis for effect:
mortality
Remarks on result:
other: Fry survival: NOEC was normalized to reflect the toxicity of LAS with a carbon chain length 11.6
Duration:
14 d
Dose descriptor:
NOEC
Effect conc.:
> 4.13 mg/L
Basis for effect:
number hatched
Remarks on result:
other: NOEC was normalized to reflect the toxicity of LAS with a carbon chain length 11.6
Duration:
196 d
Dose descriptor:
NOEC
Effect conc.:
> 4.13 mg/L
Basis for effect:
adult mortality
Remarks on result:
other: NOEC was normalized to reflect the toxicity of LAS with a carbon chain length 11.6
Duration:
196 d
Dose descriptor:
NOEC
Effect conc.:
> 4.13 mg/L
Basis for effect:
weight
Remarks on result:
other: NOEC was normalized to reflect the toxicity of LAS with a carbon chain length 11.6
Duration:
14 d
Dose descriptor:
LOEC
Effect conc.:
1.84 mg/L
Basis for effect:
mortality
Remarks on result:
other: LOEC was normalized to reflect the toxicity of LAS with a carbon chain length 11.6
Duration:
14 d
Dose descriptor:
NOEC
Effect conc.:
0.63 mg/L
Nominal / measured:
meas. (arithm. mean)
Basis for effect:
mortality
Remarks on result:
other: fry syrvival
Duration:
14 d
Dose descriptor:
NOEC
Effect conc.:
> 2.7 mg/L
Nominal / measured:
meas. (arithm. mean)
Basis for effect:
number hatched
Duration:
196 d
Dose descriptor:
NOEC
Effect conc.:
> 2.7 mg/L
Nominal / measured:
meas. (geom. mean)
Basis for effect:
adult mortality
Duration:
196 d
Dose descriptor:
NOEC
Effect conc.:
> 2.7 mg/L
Nominal / measured:
meas. (arithm. mean)
Basis for effect:
weight
Remarks on result:
other: adult fish
Duration:
14 d
Dose descriptor:
LOEC
Effect conc.:
1.2 mg/L
Nominal / measured:
meas. (arithm. mean)
Basis for effect:
mortality
Remarks on result:
other: fry survival
Details on results:
There was no effect of LAS on survival in the F0 generation or on the production of eggs. There was no difference between the control and exposed F0 generation in breeding behavior and the care of the eggs by the male. Hatchability and growth (weight) were not significantly affected in the F1 generation. Fry survival in the F1 generation was the most sensitive endpoint.

These experimental results were normalized to reflect a C11.6 chain length using a highly localized LAS-specific QSAR (Belanger et al, 2016). Toxicity normalization was performed using this basic formula:

ChVc11.6norm = ChVx * (ChVc11.6pred / ChVxpred)

Where ChV is any chronic endpoint result; such as NOEC, LOEC, EC10, etc.,
ChVc11.6norm is the normalized ChV for the test material,
ChVx is the experimental ChV for the test material,
ChVc11.6pred is the QSAR predicted ChV for the target material with a chain length of C11.6,
ChVxpred is the QSAR predicted ChV for a material with the same chain length as the test material.

A QMRF is available on the QSAR (Belanger et al, 2016) used to provide the predicted results for normalization. More details on this approach are available in the endpoint summary.
Conclusions:
The 196 day NOEC level was 0.96 mg/L and the LOEC was 1.83 mg/L based on fry survival in the F1 generation. There was no effect on adult survival, adult growth or number of eggs hatched. These results are normalized to reflect the toxicity of an LAS with a carbon chain length of 11.6. The non-normalized NOEC and LOEC are 0.63 and 1.2 mg/L respectively.
Executive summary:

A study was conducted to determine the toxicity of C12 LAS, sodium salt to Fathead minnow (Pimephales promelas) according to USEPA Method NWQL (1972). Fish were exposed to mean measured concentrations of 0, 0.34, 0.63, 1.2 and 2.7 mg/L under flow-through conditions for 196 days. The 196 d NOEC was 0.96 mg/L and the LOEC was 1.83 mg/L based on fry survival in the F1 generation. There was no effect on adult survival, adult growth or number of eggs hatched.  These results are normalized to reflect the toxicity of an LAS with a carbon chain length of 11.6.  The non-normalized NOEC and LOEC are 0.63 and 1.2 mg/L, respectively (Pickering, 1970; Belanger, 2016).


Endpoint:
fish, juvenile growth test
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
Refer to the section 13 of the dataset for details on the read across justification.
Qualifier:
equivalent or similar to
Guideline:
other: APHA 1975
GLP compliance:
no
Analytical monitoring:
no
Vehicle:
not specified
Test organisms (species):
other: Tilapia mossambica
Details on test organisms:
TEST ORGANISM
- Source: local farms
- Weight at study initiation (mean and range, SD): 0.786 ± 0.05 g
- Length at study initiation (length definition, mean, range and SD): 35.65 ± 2.06mm

FEEDING DURING TEST
- Food type: 1:1 mixture of rice bran and mustard oil cake
- Frequency: daily


ACCLIMATION
- Acclimation period: 168 hrs
Test type:
semi-static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
90 d
Hardness:
hardness 290 mg/L as CaCO3
Test temperature:
temperature 27.9 ± 0.14 °C
pH:
pH 7.1 ± 0.1
Dissolved oxygen:
dissolved oxygen 10 mg/L
Nominal and measured concentrations:
Test concentrations were 0.0, 0.25, 0.38, 0.51, and 1.10 mg a.i./L.
Details on test conditions:
TEST SYSTEM
- Test vessel: Tests were conducted in outdoor earthen vats (62 cm diameter, 30 cm mean depth)
- Renewal rate of test solution (frequency/flow rate): 15 days
- No. of organisms per vessel: 15
- Material, size, headspace, fill volume: 60-L of borehole water and 5 kg of uncontaminated soil

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Borehole water is unchlorinated water

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : feeding, growth rate, fecundity, and yield.

Reference substance (positive control):
not specified
Key result
Duration:
90 d
Dose descriptor:
NOEC
Effect conc.:
0.25 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
other: Feeding, growth rate, fecundity, yield
Duration:
90 d
Dose descriptor:
LOEC
Effect conc.:
0.51 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
other: Feeding, growth rate, fecundity, yield
Details on results:
The feeding rates decreased significantly at 0.25, 0.38 and 1.10 mg/L. No apparent difference in condition factor (K) was observed at any concentration. The maturity index (MI) of both male and female fish appeared to decrease at all concentrations, but the biological significance of this is questionable because historic control values for this parameter were not provided and the magnitude of the response did not increase with dose. Fecundity decreased at 0.51 mg/L but not at 1.10 mg/L. The gastrosomatic index (GSI) was significantly different at 0.51 and 1.10 mg/L. Based on the most reliable endpoints (GSI and fecundity), the NOEC would be 0.38 mg/L and the LOEC would be 0.51 mg/L. However, the study is incompletely documented, so details of the test substance composition and testing procedure are uncertain. True replicates were not used so statistics can not be validly conducted, though they are reported by the authors. In view of these limitations, and previous evaluations of the study which have reported a NOEC of 0.25 mg/L (van de Plassche et al., 1999), a conservative (protective) NOEC for this study is 0.25 mg/L.
Conclusions:
The 90-day NOEC for fish was 0.25 mg a.i./L. The 90-day LOEC for fish was 0.51 mg a.i./L.

Executive summary:

The long-term toxicity of the test substance to fish was determined. Groups of 15 fish were exposed to concentrations of 0.0, 0.25, 0.38, 0.51, and 1.10 mg a.i./L for 90 days. Test solutions were renewed every 15 days. The 90 -day NOEC was 0.25 mg a.i./L, and the LOEC was 0.51 mg a.i./L.

Endpoint:
fish, juvenile growth test
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Qualifier:
according to
Guideline:
other: Dutch Standard Organization NEN 6504, Determination of acute toxicity with Poecilia reticulata
GLP compliance:
no
Analytical monitoring:
no
Test organisms (species):
Poecilia reticulata
Details on test organisms:
TEST ORGANISM
- Age at study initiation (mean and range, SD): 3 to 4 weeks
- Food type: TetraMin, TetraPhyll
Test type:
semi-static
Water media type:
freshwater
Total exposure duration:
28 d
Hardness:
measured
Test temperature:
23±2°C
pH:
measured
Dissolved oxygen:
measured
Nominal and measured concentrations:
Nominal – 3.2 and 10 mg/L notes. Remaining concentrations not reported.

Details on test conditions:
TEST SYSTEM
- Material, size, headspace, fill volume: 10-L per chamber
- Renewal rate of test solution (frequency/flow rate): renewed three times per week
- No. of organisms per group Fifty
OTHER TEST CONDITIONS
- Photoperiod: circadic


EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality, growth and behavior

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3.2
Key result
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
1.88 mg/L
Basis for effect:
mortality
Remarks on result:
other: Normalized to carbon chain length C11.6
Key result
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
1.88 mg/L
Basis for effect:
behaviour
Remarks on result:
other: Normalized to carbon chain length 11.6
Key result
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
1.88 mg/L
Basis for effect:
other: growth
Remarks on result:
other: Normalized to carbon chain length 11.6
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
5.87 mg/L
Remarks on result:
other: Normalized to carbon chain length 11.6
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
3.2 mg/L
Nominal / measured:
nominal
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
3.2 mg/L
Nominal / measured:
nominal
Basis for effect:
behaviour
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
3.2 mg/L
Nominal / measured:
nominal
Basis for effect:
other: growth
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
10 mg/L
Nominal / measured:
nominal
Details on results:
The only effect (98% mortality at 10 mg/L) occurred within 2 days of study initiation.

These experimental results were normalized to reflect a C11.6 chain length using a highly localized LAS-specific QSAR (Belanger et al, 2016). Toxicity normalization was performed using this basic fo rmula:

ChVc11.6norm = ChVx * (ChVc11.6pred / ChVxpred)

Where ChV is any chronic endpoint result; such as NOEC, LOEC, EC10, etc., ChVc11.6norm is the normalized ChV for the test material,
ChVx is the experimental ChV for the test material,
ChVc11.6pred is the QSAR predicted ChV for the target material with a chain length of C11.6, ChVxpred is the QSAR predicted ChV for a material with the same chain length as the test
material.

A QMRF is available on the QSAR (Belanger et al, 2016) used to provide the predicted results for normalization. More details on this approach are available in the endpoint summary.
Conclusions:
The 28-day NOEC for fish was 1.88 mg/L based on mortality, behavior and growth. The 28-day LOEC is 5.87 mg/L. These results are normalized to reflect the toxicity of an LAS with a carbon chain length of 11.6. The non-normalized results are a 28-day NOEC of 3.2 mg/L (nominal), and 28-day LOEC was 10 mg/L (nominal).
Executive summary:

Groups of 50 Poecilia reticulata were exposed to various concentrations of the test substance for 28 days. Test solution was renewed three times per week. The 28-day NOEC for fish was 1.88 mg/L based on mortality, behavior and growth. The 28-day LOEC is  5.87 mg/L. These results are normalized to reflect the toxicity of an LAS with a carbon chain length of 11.6. The non-normalized results are a 28-day NOEC of 3.2 mg/L (nominal), and 28-day LOEC was 10 mg/L (nominal).

Endpoint:
fish, juvenile growth test
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1981
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 215 (Fish, Juvenile Growth Test)
Deviations:
no
GLP compliance:
no
Remarks:
(the study pre-dates GLPs)
Analytical monitoring:
yes
Details on sampling:
Please see the section below. The study report does not include details about sampling.
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION: Preparation of test solutions is not reported. The test concentrations were delivered to the duplicate test vessels by a modified Mount and Brungs 1L proportional diluter.
Test organisms (species):
Lepomis macrochirus
Details on test organisms:
TEST ORGANISM
- Common name: Bluegill fish
- Strain: Not reported
- Source: Not reported
- Length at study initiation: 2.5-5.0 cm
- Age at study initiation: Juvenile
- Weight at study initiation: Not reported
- Method of breeding: Not applicable
FEEDING DURING TEST
- Food type: Frozen brine shrimp
- Amount: Fed at approx. 2% of total body weight/day
- Frequency: Daily
Test type:
flow-through
Water media type:
freshwater
Limit test:
no
Total exposure duration:
28 d
Post exposure observation period:
None
Hardness:
120 mg/L CaCO3
Test temperature:
21 ± 2 °C
pH:
8.1 ± 0.2
Dissolved oxygen:
Mean Dissolved Oxygen Concentration (DOC): 7.8 mg/L (ranged, 7.0-9.0)
Nominal and measured concentrations:
Nominal test concentrations were: 0, 0.5, 1.0, 2.0, and 4.0 mg/L. MBAS and radiometric counts confirmed the expected nominal concentrations. Two figures in the study report show the confirmation of nominal test concentrations, but details not provided.
Details on test conditions:
TEST SYSTEM
- Test vessel: Aquaria
- Type: Open
- Material: 19 L glass
- Aeration: No (test was flow-through)
- Type of flow-through: Proportional diluter
- Renewal rate of test solution: 8 replacement volumes/d
- No. of organisms per vessel: Five
- No. of vessels per concentration (replicates): Two
- No. of vessels per negative control (replicates): Two
- No. of vessels per vehicle control (replicates): Not applicable
- Biomass loading rate: Not reported. There were 5 pre-weighed juvenile bluegills per each aquarium,
Loading rate was therefore 1 juvenile bluegill/4 L test solution.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution water was carbon and reverse-osmosis filtered well water of 120 mg/L CaCO3 hardness.
- Total organic carbon: Not reported
- Particulate matter: Not reported
- Metals (mg/L): Zinc: <0.001; Lead: <0.01; Iron: <0.05; Copper: <0.001,
- Nitrate (mg/L): <0.05
- Pesticides: Not reported
- Chlorine: Not reported
- Alkalinity: Not reported
- Ca/mg ratio: Not reported
- Conductivity: Not reported
- Salinity: Not applicable
- Culture medium different from test medium: Not reported
- Intervals of water quality measurement: Twice weekly
- Other:
- Temperature was monitored continuously with a recording thermograph

OTHER TEST CONDITIONS
- Adjustment of pH: Not reported
- Photoperiod: Not reported
- Light intensity: Not reported

EFFECT PARAMETERS MEASURED: (1) The growth of juvenile bluegills was determined from 10 individuals at each treatment concentration measured and weighed (wet weight) before and after the exposure. (2) Amount of 14C-LAS taken up by the fish was measured by combustion analysis.

NEGATIVE CONTROL PERFORMED: Yes (received only filtered well water)

SAMPLING
- Sampling frequency: Only on Day 28, as sampling of test species were not carried out during exposure period, to avoid disturbance of the developing fishes. On Day 28, all 10 fish per test concentration were recovered.
- Sampling method: For the amount of 14C-LAS taken up by the fish, triplicate samples of the test species were taken at 28 d sampling period, rinsed, dried at 30°C for 24 h, and weighed in tared plancets prior to combustion analyses for radiometric counting of 14C-LAS content
- Sample storage conditions before analysis: For growth rate, fish were weighed immediately after conclusion of test. For 14C-LAS analysis, samples were dried at 30°C for 24 h before analysis

RANGE-FINDING STUDY: No
Reference substance (positive control):
no
Key result
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
1 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth rate
Remarks on result:
other: Nominal concentration confirmed by analytical measurement
Details on results:
- Fish weights (individual and mean values) on day 0, 14 (if measured) and 28: Not reported
- Tank-average or pseudo-specific growth rates for periods 0-28 or 0-14 and 0-28 (if possible): Not reported
- Type of and number with morphological abnormalities: Not reported
- Type of and number with behavioural abnormalities: Not reported
- Other biological observations: Fish growth was reduced at both 2.0 and 4.0 mg/L test concentrations with no effect at 1.0 mg/L. At the end of the exposure period, test species had a biomass of 44 and 10.5 g/m2 at test concentration of 1 and 2 mg/L respectively. Control fish production was 42.5 g/m2
- Bioconcentration Data: The BCF value was found to be 252 based on a wet weight basis
- Effect concentrations exceeding solubility of substance in test medium: No
- Incidents in the course of the test which might have influenced the results: Not reported
Results with reference substance (positive control):
Positive control was not included in the study
Reported statistics and error estimates:
Not reported
Validity criteria fulfilled:
yes
Conclusions:
The 28 d NOEC of C11.6 LAS to juvenile Bluegills (Lepomis macrochirus) was 1 mg a.i./L, based on growth rate in a flow-through model ecosystem study. Analytical measurements confirmed the nominal test concentrations.
Executive summary:

A long term toxicity test to fish (juvenile Lepomis macrochirus) was conducted on C11.6 LAS (linear alkylbenzene sulfonate) generally following the OECD 215 test guideline. The growth of juvenile bluegills was determined after 28 days in a flow-through model ecosystem study. The nominal test concentrations were 0, 0.5, 1.0, 2.0, and 4.0 mg a.i./L, confirmed by analytical measurements.

 

The growth of juvenile bluegills (wet weight after 28 d exposure) was not affected at 0.5 and 1.0 mg a.i./L, but was reduced at 2.0 and 4.0 mg a.i./L. At the end of the exposure period, fish at 1.0 mg a.i./L LAS had a biomass of 44 gm/m2 compared to 10.5 gm/m2 for the 2.0 mg/L concentration, and 42.5 gm/m2 for the controls.

 

The No observed effect concentration (NOEC) was 1.0 mg a.i./L, based on growth rate.

This Chronic toxicity test is classified as acceptable, and satisfies the guideline requirements for the OECD 215.


Description of key information

MEA-LAS dissociates into MEA and LAS in water. Since both MEA and LAS are readily biodegradable, chronic toxicity to the aquatic environment is not expected. Testing has however been conducted on LAS and the key studies are presented. Toxicity values were normalized to reflect an LAS chain length of 11.6 using a robust and highly localized fish LAS (Q)SAR (Belangeret al., 2016). The model was built from high quality toxicity data using pure LAS chain lengths (C10-14). Further external validation was performed using LAS mixtures with different average alkyl chain lengths.  Reporting Format (QMRF) documents describing data quality, model development and performance of the model are appended to the Robust Study Summary (RSS).

Study 1 (C10-13 LAS): 

Fertilized eggs of Rainbow trout (Salmo gairdneri) were exposed to C10-13 LAS, sodium salt (average chain length C11.6) at mean measured concentrations of 0, 0.03, 0.23, 0.35, 0.63, 0.95 and 1.9 mg/L for 72 d under flow-through conditions. The responses recorded included egg survival, time to eyed egg stage, time to hatch, survival and final weight of sac-fry (eleutheroembryos), time and extent of swim-up (external feeding). The lowest NOEC value found was 0.23 mg/L based on survival of eggs exposed from eyed stage, survival of eggs exposed from fertilization, survival of sac fry and overall survival from fertilization to swim-up. The data are for C11.6 LAS and no normalization is required (Marshall, 2010).  

Study 2 (C12 LAS):  

A study was conducted to determine the toxicity of C12 LAS, sodium salt to Fathead minnow (Pimephales promelas) according to US EPA Method NWQL (1972). Fish were exposed to mean measured concentrations of 0, 0.34, 0.63, 1.2 and 2.7 mg/L under flow-through conditions for 196 days. The 196 d NOEC was 0.96 mg/L and the LOEC was 1.83 mg/L based on fry survival in the F1 generation. There was no effect on adult survival, adult growth or number of eggs hatched. These results are normalized to reflect the toxicity of LAS with a carbon chain length of 11.6 (Belanger, 2016). The non-normalized NOEC and LOEC are 0.63 and 1.2 mg/L, respectively (Pickering, 1970). 

Study 3 (C10-13 LAS): 

The long-term toxicity of C10-13 LAS, sodium salt (average chain length C11.6) to Mozambique tilapia (Tilapia mossambica) was determined. Groups of 15 fish were exposed to concentrations of 0.0, 0.25, 0.38, 0.51 and 1.10 mg a.i./L for 90 d according to a method similar to APHA, 1975. Test solutions were renewed every 15 d. The 90 d NOEC was 0.25 mg a.i./L and the LOEC was 0.51 mg a.i./L, based on nominal values (Chattopahyay, 1985). 

Study 4 (C10 -13 LAS): 

Groups of 50 guppies (Poecilia reticulata) were exposed to various concentrations of C10-13 LAS, sodium salt for 28 d according to the Dutch Standard Organization Method NEN 6504. Test solutions were renewed three times per week. The 28 d NOEC was 1.88 mg/L based on mortality, behavior and growth. The 28 d LOEC was 5.87 mg/L (nominal). These results are normalized to reflect the toxicity of an LAS with an average carbon chain length of 11.6 (Belanger, 2016). The non-normalized results are a 28 d NOEC of 3.2 mg/L (nominal) and 28 d LOEC of 10 mg/L (nominal) (Canton, 1982).

Study 5 (C10-13 LAS): 

A long-term toxicity test in juvenile Bluegill sunfish (Lepomis macrochirus) was conducted with C10-13 LAS, sodium salt (average chain length C11.6) according to a method generally following OECD Guideline 215. The growth of the fish was determined after 28 d in a flow-through model ecosystem. The nominal test concentrations were 0, 0.5, 1.0, 2.0 and 4.0 mg a.i./L, confirmed by analytical measurements. Growth (wet weight after 28 d exposure) was not affected at 0.5 and 1.0 mg a.i./L, but was reduced at 2.0 and 4.0 mg a.i./L. At the end of the exposure period, fish at 1.0 mg a.i./L had a biomass of 44 gm/m2 compared to 10.5 gm/m2 for the 2.0 mg/L concentration and 42.5 gm/m2 for the controls. The NOEC was 1.0 mg a.i./L, based on growth rate (Maki, 1981; Larson, 1982). 

Key value for chemical safety assessment

EC10, LC10 or NOEC for freshwater fish:
0.23 mg/L

Additional information

The point of departure for aquatic PNEC derivation is the 56 d NOEC of 0.268 mg/L from a mesocosm model ecosystem (Belanger, 1997, 2002 and 2004; Lowe, 1996).