Neodymium trinitrate

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish early-life stage toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 16 March 2020 to 20 August 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 210 (Fish, Early-Life Stage Toxicity Test)

Version / remarks:

2013

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Samples were taken from the control and all surviving test groups.
- Sampling method: Water samples were taken and filtered through a 0.45μm cellulose acetate filter from the freshly prepared bulk test preparation on Days 0, 6, 13, 20, 27 and 32 and from the corresponding old or aged media on Days 1, 7, 14, 21, 28 and 33 (cycling between replicates) for quantitative analysis.
- Sample storage conditions before analysis: The fresh samples were stored frozen prior to analysis with the corresponding old samples which were analysed on the day of sampling.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: For preparation of fresh test solutions on Days 0 to 14 a nominal amount of test item (9.0 mg) was dissolved in modified ISO test media and the volume adjusted to 5 litres to give a 1.0 mg/L neodymium trinitrate stock solution from which a series of dilutions were made to give the required test concentrations of 0.0128, 0.032, 0.080, 0.20 and 0.50 mg/L as neodymium trinitrate. The 0.50 mg/L test concentration was not prepared after Day 7 as there were no surviving fish. For the preparation of fresh test solutions on Day 15 until end of the test a nominal amount of test item (18 mg) was dissolved in modified ISO test media and the volume adjusted to 10 litres to give a 1.0 mg/L neodymium trinitrate stock solution from which a series of dilutions were made to give the required test concentrations of 0.0128, 0.032, 0.080 and 0.20 mg/L as neodymium trinitrate. The stock solution was inverted several times to ensure adequate mixing and homogeneity. The prepared concentrations were, depending upon the volume required, either inverted several times, or stirred via magnetic stirrer for a period of 5 minutes to ensure adequate mixing and homogeneity.
- Controls: The control group was maintained under identical conditions but not exposed to the test item.
- Test concentration separation factor: 2.5
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): no

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: Fathead Minnows
- Strain: Pimephales promelas
- Method of breeding: The test was initiated with newly fertilized eggs of fathead minnows (Pimephales promelas). The adult fathead minnows that produced the eggs for the test were bred and maintained in dechlorinated tap water with a Tropic Marine Centre 2500 recirculated system. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. In the 7 days preceding the start of the test, the water temperature was controlled at 25 to 26 °C with a dissolved oxygen content of greater than or equal to 7.0 mg O2/L. The breeding stock fish were fed daily with ZM small granular fish food and frozen brine shrimp. The diet and diluent water are considered not to contain any contaminant that would affect the integrity and outcome of the study.
- Source: Laboratory cultures.

METHOD FOR PREPARATION AND COLLECTION OF FERTILIZED EGGS
- Method of collection of fertilised eggs: Each breeding tank was supplied with inverted plastic guttering for the fish to lay eggs on and be fertilized. The eggs were visually inspected before introduction into the test system and were identified as being at early blastodisc stage.

POST-HATCH FEEDING
- Start date: 2 days post-hatch
- Type/source of feed, amount given and frequency of feeding: freshly hatched brine shrimp nauplii at a rate of 2.0 to 40 μL per fry/larvae split into two portions except for Day 7 and 32 where the larvae were only fed one portion of feed.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

33 d

Remarks on exposure duration:

(28 days post-hatch)

Hardness:

Start of the test : 246 to 252 mg/L as CaCO3.
Termination of the test: 252 to 264 mg/L as CaCO3.

Test temperature:

Recorded in a surrogate vessel by a Testo temperature logger: 23.9 to 26.1 °C.
Recorded in each test vessel before and after each media renewal: 24 to 26 °C.
Variation between test chambers: ± 1.3°C.
Variation Between successive days: ± 1.8°C.

pH:

From 5.9 to 8.3

Dissolved oxygen:

>= 6.0 mg/L

Salinity:

Not concened

Conductivity:

513 μS/cm at 20 °C (Typical dechlorinated water characteristics)

Nominal and measured concentrations:

- Nominal concentrations: control, 0.0128, 0.032, 0.080, 0.20 and 0.50 mg Nd(NO3)3/L.
- Geometric mean measured concentrations: control, 0.010, 0.024, 0.061, 0.17 and 0.49 mg Nd(NO3)3/L (i.e.: 0.0046, 0.010, 0.027, 0.073, 0.22 mgNd/L).

Details on test conditions:

TEST SYSTEM
- Test vessel: 1 liter glass vessels were used from Day 0 to Day 14 and from Day 15 to the end of the test 5 liter glass vessels were used. Glass vessel size was increased during the test to account for organism growth.
- Type (delete if not applicable): the vessels were covered to reduce evaporation
- Fill volume: The approximate volume of test preparation in each vessel was 400 mL from Day 0 to Day 6, 800 mL from Day 7 to Day 14 and 4000 mL from Day 15 to Day 33. Test preparation volume was increased during the test to account for organism growth.
- Aeration: via narrow bore glass tubes from Day 8 onwards
- Renewal rate of test solution (frequency/flow rate): daily from the start of the test, with the exception of Day 3 where there was no water change to avoid causing premature hatching.
- No. of fertilized eggs/embryos per vessel: 20
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ISO medium (CaCl2.2H2O: 294 mg/L, MgSO4.7H2O: 123
mg/L, NaHCO3: 65 mg/L, KCl: 5.8 mg/L). The reconstituted water had a pH of 6.0 and was aerated until the dissolved oxygen concentration was approximately air-saturation value. The pH of the medium was adjusted to 6.0 in order to aide solubilization and stability of the test item. The reconstituted water had an approximate theoretical total hardness of 250 mg/L as CaCO3.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods
- Light intensity: 546 to 625 Lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
- Recorded daily: number of dead eggs (up to completion of hatching), dead and live larvae and any sub-lethal effects
- At test termination: total length and wet weight of the surviving fish

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
- Test concentrations: 0.010, 0.10, 1.0 and 10 mg/L as neodymium trinitrate
- Results used to determine the conditions for the definitive study: No difference was observed between the control and test concentrations of 0.010 and 0.10 mg/L neodymium trinitrate in terms of hatching, survival and growth (wet weight). 100% mortality was observed at test concentrations of 1.0 and 10 mg/L neodymium trinitrate. Test concentrations for the definitive study were selected on this basis.

POST-HATCH DETAILS
- Begin of post-hatch period: Day 4
- No. of hatched eggs (alevins)/treatment: See in "Any other information on results incl. tables"

Reference substance (positive control):

not specified

Duration:

33 d

Dose descriptor:

NOEC

Effect conc.:

>= 0.49 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

other: Number Hatched

Remarks on result:

other: i.e.: >= 0.22 mg/L as neodymium element

Duration:

33 d

Dose descriptor:

NOEC

Effect conc.:

0.061 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

other: Post-hatch Survival

Remarks on result:

other: i.e.: 0.027 mg/L as neodymium element

Key result

Duration:

33 d

Dose descriptor:

LC10

Effect conc.:

0.081 mg/L

95% CI:

0.04 - 0.11

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

other: Post-hatch Survival

Remarks on result:

other: i.e.: 0.035 mg/L as neodymium element (CI95%: 0.029 – 0.040)

Duration:

33 d

Dose descriptor:

NOEC

Effect conc.:

0.061 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

length

Remarks on result:

other: i.e.: 0.027 mg/L as neodymium element

Duration:

33 d

Dose descriptor:

EC10

Effect conc.:

> 0.17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

length

Remarks on result:

other: i.e.: > 0.073 mg/L as neodymium element

Duration:

33 d

Dose descriptor:

NOEC

Effect conc.:

0.024 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

weight

Remarks:

Wet Weight

Remarks on result:

other: i.e.: 0.010 mg/L as neodymium element

Duration:

33 d

Dose descriptor:

EC10

Effect conc.:

0.16 mg/L

95% CI:

0.002 - 97

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

Neodymium Trinitrate

Basis for effect:

weight

Remarks:

Wet Weight

Remarks on result:

other: i.e.: 0.068 mg/L as neodymium element

Details on results:

Results are detailed below.

Number of Eggs Hatching
The start of egg hatching for the control and all test concentrations was observed on Day 4 of the test and completion of hatching was observed on Day 6 of the test (see Table 1 below). Statistical analysis of the hatching data give results detailed below inTable 2. There were no statistically significant differences (P≥0.05), between the control and all of the test groups with mean hatching rates ranging from 85% to 93%.

Post-hatch Survival
The percentage of eggs hatched and post-hatch survival are given in Table 3. Statistical analysis of the hatching data give results detailed below in Table 4. There were no statistically significant difference between the control and 0.010, 0.024 and 0.061 mg/L neodymium trinitrate test concentrations (P≥0.05), (corresponding to 0.0046, 0.010 and 0.027 mg/l neodymium) with mean post-hatch survival rates ranging from 87% to 93%. However, the two other test concentrations were significantly different (P<0.05) with mean post-hatch survival rates of 28% and 0% in the 0.17 and 0.49 mg/L neodymium trinitrate test concentration groups, respectively (corresponding to 0.073 and 0.22 mg/L neodymium).

Total Length and Weight Data
The total length and wet weight data for all fish alive at the end of the test are given in Table 5. No body length or wet weight was generated at 0.49 mg/L as neodymium trinitrate (corresponding to 0.22 mg/L neodymium) due to 100% mortality. Statistical analysis of the fish total length give results detailed below in table 6. There were no statistically significant differences between the control, 0.010, 0.024 and 0.061 mg/L neodymium trinitrate test concentrations (P≥0.05) (corresponding to 0.0046, 0.010 and 0.027 mg/L neodymium). However, the test concentration of 0.17 mg/L neodymium trinitrate (corresponding to 0.073 mg/L neodymium) was significantly different (P<0.05) with total length being reduced by 4.2% as compared to control. Statistical analysis of the fish body weight data give results detailed below in table 7. There were no statistically significant differences between the control, 0.010 and 0.024 mg/L neodymium trinitrate test concentration (P≥0.05) (corresponding to 0.0046 and 0.010 mg/L neodymium. However, the two other test concentrations of 0.061 and 0.17 mg/L neodymium trinitrate (corresponding to 0.027 and 0.073 mg/L neodymium) were significantly different (P<0.05) with wet weight being reduced by 7.6% and 9.9% as compared to control, respectively.

Observations
The majority of the abnormal observations were observed at 0.17 and 0.49 mg/L as neodymium trinitrate (equivalent to 0.073 and 0.22 mg/L as neodymium) and included the following observations; abnormal development, pale fish, under developed, lethargic and kinked and curved spine. Abnormal observations were also observed in the control, 0.010, 0.024 and 0.061 mg/L as neodymium trinitrate (equivalent 0.0046, 0.010 and 0.027 mg/L as neodymium). The observations were curved spine, abnormal development, kinked spine, small fish and pale fish. Therefore, these observations are considered to be due to defects occurring in a natural population, and not attributable to exposure of the test item.

Verification of test concentrations
Analysis of the fresh test preparations on Days 0, 6, 13, 20, 27 and 32 showed measured test concentrations to range from 0.0084 to 0.61 mg/L as neodymium trinitrate (69% to 121% of nominal), equivalent 0.0039 to 0.27 mg/L as neodymium. Analysis of the old test preparations on Days 1, 7, 14, 21, 28 and 33 showed measured concentrations to range from less than the Limit of Quantification (LOQ), which was determined to be 0.0050 mg/L to 0.49 mg/L as neodymium trinitrate (19.5% to 99% of nominal), equivalent to less than the LOQ, which was determined to be 0.0022 mg/L to 0.21 mg/L as neodymium. It was noted that on Day 6, analysis of the 0.0128 mg/L as neodymium trinitrate test group showed measured concentration of approximately 330% of nominal concentration, however given that the Day 7 analysis of this test concentration measured concentrations within the range of the old analysis sample it can be considered that this measured concentration on Day 6 is an analytical anomaly/error. As this result did not affect the geometric mean measured test concentrations it was included within the calculation. Given the decline in test concentrations in the aged test preparations it was considered appropriate to calculate the results based on the geometric mean measured test concentrations. The geometric mean measured concentrations were calculated for the following media renewal periods: Days 0 to 1, 6 to 7, 13 to 14, 20 to 21, 27 to 28 and 32 to 33, and the arithmetic mean of the six values determined. Where a measured concentration of less than the LOQ of the analytical method was determined, a value of half the LOQ was substituted into the equation.

Results with reference substance (positive control):

No data available

Reported statistics and error estimates:

ECx Calculations
The LC/ECx values in terms of hatching were calculated by Probit Analysis using Linear Maximum-Likelihood regression. The LCx values and associated confidence limits and the slope of response curve and its standard error in terms of post-hatch survival were calculated by Weibull Analysis using Linear Maximum-Likelihood regression. The ECx values in terms of the weights of the fish were calculated by 2-Parameter Logistic Cumulative Distribution Function and the length of the fish were calculated by 2-Parameter Normal Cumulative Distribution Function. All results were calculated using the ToxRat Professional computer software package (ToxRat Professional Version 3.3.0).

LOEC and NOEC
For the estimation of the LOEC and the NOEC values the hatching data for the control and each test group were compared using the Chi2 2x2 Table Test with Bonferroni Correction incorporating Qualitative Trend Analysis by Contrasts and the post-hatch survival data for the control and each test group were compared using Multiple Sequentially-rejective Fisher Test after Bonferroni-Holm incorporating Tarone’s test and Qualitative Trend Analysis by Contrasts. The total length and wet weight data for the control and each surviving test group obtained on termination of the test were compared using Williams Multiple Sequential t-test incorporating Trend Analysis by Contrasts, Levene’s test on Variance Homogeneity and Shapiro-Wilk’s test on Normal Distribution. All results were calculated using the ToxRat Professional computer software package (ToxRat Professional Version 3.3.0).

Table 1: Number of Dead Eggs in the Definitive Test

Geometric Mean Measured Concentration (mg/L neodymium trinitrate)		Number of Dead Eggs (Initial Population = 20)
		Days						Total
		1	2	3	4	5	6*
Control	R1	2	0	0	0	0	0	2
	R2	0	0	0	0	1	0	1
	R3	3	0	0	0	0	0	3
	R4	2	0	0	0	2	0	4
0.010	R1	1	0	0	1	0	0	2
	R2	2	0	0	0	0	0	2
	R3	0	0	0	0	1	0	1
	R4	1	0	0	0	0	0	1
0.024	R1	2	0	0	0	0	0	2
	R2	0	1	0	1	1	0	3
	R3	0	0	0	0	0	0	0
	R4	3	0	0	0	0	0	3
0.061	R1	1	0	1	0	0	0	2
	R2	2	0	0	0	0	0	2
	R3	1	0	0	1	0	0	2
	R4	1	0	0	0	0	0	1
0.17	R1	3	0	0	0	0	0	3
	R2	2	0	0	0	0	0	2
	R3	1	0	0	0	0	0	1
	R4	1	1	0	0	0	0	2
0.49	R1	3	0	0	0	1	0	4
	R2	1	0	0	1	3	0	5
	R3	0	0	0	0	0	0	0
	R4	3	0	0	0	0	0	3

* All surviving eggs hatched by day 6

R = Replicate

 

Table 2: Hatching results

	Endpoint	Concentration (mg/L as  Neodymium) [95% Confidence Limits]	Concentration (mg/L as Neodymium Trinitrate) [95% Confidence Limits]
	No Observed Effect Concentration	≥0.22	≥0.49
	Lowest Observed Effect Concentration	Not determined	Not determined

Calculated by Chi² 2x2 Table test with Bonferroni Correction incorporating Qualitative Trend Analysis by Contrasts.

 

Table 3: Hatching and Post Hatch Survival in the Definitive Test

Geometric Mean Measured Concentration (mg/L neodymium trinitrate		Hatching Rate (%)	Mean Hatching Rate (%)	Survival Rate (%)	Mean Survival Rate (%)
Control	R1	90	88	83	88
	R2	95		74
	R3	85		94
	R4	80		100
0.010	R1	90	93	89	87
	R2	90		83
	R3	95		95
	R4	95		79
0.024	R1	90	90	94	89
	R2	85		76
	R3	100		90
	R4	85		94
0.061	R1	90	91	83	93
	R2	90		100
	R3	90		94
	R4	95		95
0.17	R1	85	90	24	28^*
	R2	90		22
	R3	95		32
	R4	90		33
0.49	R1	80	85	0	0*
	R2	75		0
	R3	100		0
	R4	85		0

R       = Replicate

^*        = Statistically significant different form the control

 

Table 4: Post-hatch survival results

	Endpoint	Concentration (mg/L as Neodymium) [95% Confidence Limits]	Concentration (mg/L as Neodymium Trinitrate) [95% Confidence Limits]
Post-hatch Survival	LC10	0.035 (0.029 – 0.040)	0.081 (0.040 – 0.11)
	LC20	0.045 (0.039 – 0.049)	0.10 (0.063 – 0.13)
	LC50	0.063 (0.058 – 0.069)	0.15 (0.11 – 0.19)
	No Observed Effect Concentration	0.027	0.061
	Lowest Observed Effect Concentration	0.073	0.17

Calculated by Weibull analysis using Linear Maximum Likelihood Regressions (LCx determinations) and Multiple Sequentially-rejective Fisher test after Bonferroni-Holm incorporating Tarone’s test and Qualitative Trend Analysis by Contrasts (LOEC/NOEC determinations).

 

Table 5: Total Length and Weight Data

Geometric Mean Measured Concentration (mg/L neodymium trinitrate)		Total Length (mm)		Group Mean Total Length (mm)	Wet Weight (mg)		Group Mean Wet Weight Weight (mg)
		Average	SD		Average	SD
Control	R1	20.71	1.07	20.67	76.3	15.26	74.5
	R2	20.78	0.76		77	10.94
	R3	20.45	0.69		71.5	9.28
	R4	20.74	0.8		73.1	10.36
0.010	R1	20.59	1.21	20.83	71.4	13.24	76.2
	R2	21.04	0.9		78.7	10.37
	R3	20.6	0.89		73.8	11.02
	R4	21.09	1		80.5	12.27
0.024	R1	20.36	1.18	20.75	73.4	13.67	76.7
	R2	21.24	0.9		79.6	11.4
	R3	20.75	0.89		77.2	12.38
	R4	20.66	1.44		76.7	18.49
0.061	R1	20.66	1.34	20.32	74.7	14.54	68.8
	R2	20.3	1.25		70.1	14.29
	R3	20.28	1.1		63.5	11.44
	R4	20.03	1.5		66.9	15.13
0.17	R1	19.43	2.26	19.81	66.4	20.49	67.2
	R2	20.34	0.5		72	10.73
	R3	19.3	1.67		63.2	16.32
	R4	20.17	0.83		67.1	9.78

R = Replicate

Calculated by 2-Parameter Normal Cumulative Distribution Function and Williams Multiple Sequential t-test incorporating Trend Analysis by Contrasts, Levene’s test on Variance Homogeneity and Shapiro-Wilk’s test on Normal Distribution

 

Table 6: Total Length results

	Endpoint	Concentration (mg/L as Neodymium) [95% Confidence Limits]	Concentration (mg/L as Neodymium Trinitrate) [95% Confidence Limits]
Body Length	EC10	>0.073	>0.17
	No Observed Effect Concentration	0.027	0.061
	Lowest Observed Effect Concentration	0.073	0.17

Calculated by 2-Parameter Normal Cumulative Distribution Function (ECx determinations) and Williams Multiple Sequential t-test incorporating Trend Analysis by Contrasts, Levene’s test on Variance Homogeneity and Shapiro-Wilk’s test on Normal Distribution (LOEC/NOEC determinations).

 

Table 7: Wet weight results

	Endpoint	Concentration (mg/L as Neodymium) [95% Confidence Limits]	Concentration (mg/L as Neodymium Trinitrate) [95% Confidence Limits]
Wet Weight	EC10	0.068	0.16 (0.0020 – 97)
	EC20	>0.073	>0.17
	No Observed Effect Concentration	0.010	0.024
	Lowest Observed Effect Concentration	0.027	0.061

Calculated by 2-Parameter Normal Cumulative Distribution Function (ECx determinations) and Williams Multiple Sequential t-test incorporating Trend Analysis by Contrasts, Levene’s test on Variance Homogeneity and Shapiro-Wilk’s test on Normal Distribution (LOEC/NOEC determinations).

 

Validity Criteria

The following validity criteria were achieved during the test and the test was considered as valid:

Criteria	Required	Achieved
Dissolved oxygen	Equal to or greater than 60% ASV	73% ASV
Water temperature
Between test chambers	±1.5 ^oC	±1.3^oC
Between successive days	±1.5 ^oC	±1.8^oC
Control hatching success rate	>70%	87.5%
Control post-hatch survival	>75%	87.1%

A minor deviation was observed as the variation in water exceeded ±1.5°C on occasion between successive days.

All other validity criteria were met and this minor derivation is not thought to have affect the outcome of the study.

 

Validity criteria fulfilled:

yes

Remarks:

See details above

Conclusions:

Exposure of the early-life stages of Pimephales promelas to Neodymium Trinitrate during 33 days gave the following results based on the geometric mean measured test concentrations of Neodymium Trinitrate:
- Number Hatched: NOEC ≥ 0.49 mg/L
- Post-hatch Survival: NOEC = 0.061 mg/L, and LC10 = 0.081 mg/L  (CI95: 0.040 – 0.11 mg/L)
- Body Length: NOEC = 0.061 mg/L, EC10 > 0.17 mg/L 
- Wet Weight: NOEC = 0.024 mg/L, EC10 =0.16 mg/L  (CI95: 0.0020 – 97 mg/L)

Executive summary:

The chronic toxicity of neodymium trinitrate to Pimephales promelas was determined in a 33 days semi-static test according to the OECD guideline 210 and in compliance with the principles of Good Laboratory Practice.

Based on the results of a preliminary range-finding test, newly fertilized fathead minnow eggs (4 replicates of 20 eggs per group) were exposed to a control treatment and to solutions of the test item at nominal concentrations of 0.0128, 0.032, 0.080, 0.20, 0.50 mg/L neodymium trinitrate at a temperature of 24 to 26 °C. To these nominal concentrations corresponded the following geometric mean measured test concentrations: 0.010, 0.024, 0.061, 0.17 and 0.49 mg/L as neodymium trinitrate. In order to maximize the dissolved concentrations of the test item, fish were exposed in test media adjusted to pH 6.0. The mortalities and any sub-lethal effects of exposure in each test and control vessel were recorded daily until termination of the test (28 days post-hatch).

The following results were determinated based on the geometric mean measured test concentrations of Neodymium Trinitrate:

- Number Hatched: NOEC ≥ 0.49 mg/L

- Post-hatch Survival: NOEC = 0.061 mg/L and LC10 = 0.081 mg/L (CI95: 0.040 – 0.11 mg/L)

- Body Length: NOEC = 0.061 mg/L, EC10 >0.17 mg/L 

- Wet Weight: NOEC = 0.024 mg/L, EC10 = 0.16 mg/L (CI95: 0.0020 – 97 mg/L)

All validation criteria for the study were satisfied with the exception of a minor variation (in water temperature) that is not thought to have affect the outcome of the study.

Description of key information

Under the conditions of this study, chronic toxic effects on Pimephales promelas have been observed:

- Based on larval survival rates (Post-hatch Survival): 33d-NOEC = 0.061 mg/L, 33d-LC10 = 0.081 mg/L.

- Based on body length: 33d-NOEC = 0.061 mg/L, 33d-EC10 > 0.17 mg/L.

- Based on wet weight: 33d-NOEC = 0.024 mg/L, 33d-EC10: 0.16 mg/L.

(Concentrations expressed in mg/L neodymium trinitrate)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC10

Remarks:

Post-hatch Survival

Effect concentration:

0.081 mg/L

Additional information

An experimental study performed under GLP compliance and in accordance with OECD TG 210 was flagged as a key study and assigned a Klimisch score of 1. It revealed adverse effects on post-hatch survival, wet weight and body length in Pimephales promelas.