1-nitroguanidine

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

fish early-life stage toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Goodman, 1986. Proposed new standard guide for conducting early life-stage toxicity tests with fishes. Draft No. 10. American Society for Testing and Materials.

GLP compliance:

not specified

Specific details on test material used for the study:

Test substance supplier U.S Naval Ordnance Station
Lot No 985-1
Essay 99.998%

Analytical monitoring:

yes

Details on sampling:

- Water quality and samples for HPLC measurements were taken daily from alternating replicates of all treatments at time 0 h and every 24 h
- Sample storage conditions before analysis: in the cases samples could not be analysed immediately following filtration, the filtered samples were stored at 4 °C in amber glass vials fitted with Teflon-lined caps and analyzed within 24 h from the time the samples were originally taken from the test aquaria.

Vehicle:

no

Details on test solutions:

PREPARATION OF STOCK SOLUTION:
- Saturated stock solutions were prepared by dissolving appropriate amounts of matrial in aerated diluent water
- Stock solutions were stirred in the dark for 24 h at room temperature
- Occasionally the test material was heated to ~30 °C
- All stock solutions were filtered before use to remove particles > 0.45 µm as well as excess reagent crystals in saturated solutions
- All stock solutions were prepared in amber glass containers
- The highest toxicant concentartion tested was the solubility limit of the test material in JHU/APL (John Hopkins University Applied Physics Laboratory) well water at the test temperature

APPLICATION OF STOCK/TEST SOLUTIONS:
- Test solutions were delivered by solenoid-activated proportional dilutor systems which were calibrated 24 h prior to the start of a test and checked and/or recalibrated at a minimum twice daily during a test
- The dilutors were constructed of glass; polyethylene fittings and Tygon tubing were also used
- Control and test solutions, which were held at the test temperature, were aerated in their respective headboxes (polyethylene or fibreglass tanks) with air supplied by an oil-free compressor
- All stock concentrations were quantified prior to the start of a test, and each time a new stock solution was prepared during the test
- All dilutors were equipped with counters to monitor the cycling rate as well as to ensure proper function of the dilutor
- All stock solutions were kept in the dark to avoid photolysis

- Controls: test solution without NQ

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow
- Source: * Juveniles and embroys from JHU/APL (John Hopkins University Applied Physics Laboratory) culture, maintained at 25 +/- 1 °C in JHU/APL well water;
* JHU/APL culture procedures were similar to those recommended by Peltier and Weber (1985)
* The JHU/APL culture was initiated with mature fathead minnows obtained from the U.S. EPA Environmental Monitoring and Support Laboratory - Cincinnati, Ohio
- Briefly spawning fish were cultured in fibreglass tanks (2.4 x 0.8 x 0.5 m) containing 0.2 m³ JHU/APL well water held at 25 +/-1 °C
- Spawning adults were fed a diet of frozen brine shrimp (Artemia sp.) and TetraMin staple food twice daily
- Excess food was removed daily
- Five sets of spawning fathead minnows were maintained in the culture tanks at a ratio of 1 male : 3 females.
- Replacement spawners were rotated at approx. 3-month intervals
- Fathead minnow embryos were collected on spawning substrates (10 cm I.D. x 20 cm long PVC pipe sections cut longitudinally in equal portions
- Fry were reared on brine shrimp nauplii (< 24 h old) in 19 L aquaria at 25 +/- 1 °C in JHU/APL well water.
- No fish embryos were used for testing if they exhibited any signs of disease.
- No post-hatch fish were used if they exhibited any symptoms of disease within 10 days preceding the start of a test.
- All stages of were reared under a 16 h light : 8 h dark photoperiod (fluorescent light; 60-85 foot candles at the surface of the culture vessels.
- Age of embryos at study initiation: < 12 h

POST-HATCH FEEDING
- Start date: day 2 post-hatch
- Type/source of feed: live brine shrimp (< 24 h)
- Amount given: approx. 4 % dry food/wet weight fish
- Frequency of feeding: three times daily on weekdays and two times daily on weekends

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

32 d

Remarks on exposure duration:

4-d embryo exposure and 28-d post-hatch exposure

Post exposure observation period:

None

Hardness:

183 mg/l (as CaCO3)

Test temperature:

25.3 (24.9-26.0) °C

pH:

8.1 (7.8-8.3)

Dissolved oxygen:

8.2 (7.3-8.8) mg/l

Salinity:

no data

Nominal and measured concentrations:

- Nominal concentrations: 0, 480, 810, 1330, 2200, 3700 mg/l
- Mean measured concentrations: 0, 380, 610, 1050, 2030, 4040 mg/l

Details on test conditions:

TEST SYSTEM
- Emybro cups (if used, type/material, size, fill volume): glass cylinders (50 mm diameter I.D.; 200 ml volume) fitted with teflon screens
- Test vessel:
- Type: open
- Material, size, fill volume: 10 l glass test chambers with 6.4 l of test solution
- During the embryo incubation periods, the embryos were held in embryo cups constructed of glass cylinders (50 mm diameter I.D.; 200 ml
volume) fitted with teflon screens that were supended in the 10 l test chambers on a rocker arm apparatus and reciprocated vertically at 2 rpm
to insure good mixing within the embryo cups
- Type of flow-through: proportional diluter
- No. of fertilized eggs/embryos per vessel: 30
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Test temperature was maintained by placing the exposure vessel in constant temperature water baths
- Toxicant concentrations were established in the 10 l test chambers 24 h prior to the introduction of the embryos
- Recently hatched larvae were released immediatly to the test chambers by lowing the embryo incubation cups below the surface of the test solution allowing the fish to swim free
- Any embryos with fungus were removed from the test systems and counted
- Embryos removed with fungus were not included in the calculations of hatching success


TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: non-chlorinated deep well located at JHU/APL
- Total organic carbon: 19 mg/l
- Metals: all below L.O.D.
- Pesticides: all below L.O.D.
- Chlorine: not chlorinated
- Alkalinity: 104 mg/l (as CaCO3)
- Conductivity: 325 µmhos/cm
- Intervals of water quality measurement: daily


OTHER TEST CONDITIONS
- Photoperiod: 16 h light / 8 h dark
- Light intensity: < 25 foot candles until swim-up


EFFECT PARAMETERS MEASURED: hatching success, growth and survival


POST-HATCH DETAILS
- Post-hatch fish were observed daily for developmental abnormalities and mortality
- Feeding: live brine shrimp (< 24 h) beginning at day 2 post-hatch three times daily on weekdays and two times daily on weekends
- Amount of food: approx. 4 % dry food/wet weight fish
- Excess food and feces were siphoned from test chambers at least daily
- At the conclusion of the test, total length, blotted wet weight, and dry weight were determined for all fish from each treatment
- Dry weight was determined by drying at 60 °C for a minimum of 24 h or longer until a constant weight occurred
- Morphometric data were not taken on fish that died while a test was in progress

Reference substance (positive control):

no

Duration:

28 d

Dose descriptor:

LOEC

Effect conc.:

2 030 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

length

Remarks on result:

other: post-hatch exposure

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

1 050 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

length

Remarks on result:

other: post-hatch exposure

Details on results:

- A 4-d exposure to NQ at the solubility limit of the compound (4040 mg/l) did not affect the hatching success of the embryos.
- A 28-d post-hatch exposure at 4040 mg/l killed all fish; significant mortality (α = 0.05) did not occur at a concentration of 2030 mg/l or lower
- A significant reduction (α = 0.05) did in mean total length occurred at 2030 mg/l.
- A statistically significant (α = 0.05) effect did not occur for wet weight and dry weight at 2030 mg/l; although, the data indicate that wet weight and dry weight were reduced at 2030 mg/l.
- The LOEC and NOEC for the fathead minnow, based on a reduction in total length are 2030 and 1050 mg/l, respectively.
- A total of four fish with curved spines were observed to occur randomly in the test treatments during the 28-d exposure
- For further details see table 1.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

- Mean measured concentrations were used in the statistical analyses

Percent hatch of eyed embryos:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: data fail to meet the homogeneity of variance assumption
- Kruskal-Wallis Test: all groups are equal

Percent survival larvae after 28 days of post-hatch exposure:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: variances are homogenous
- ANOVA: all groups are eqal

Total length of larvae after 28 days of post-hatch exposure:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: variances are homogenous
- ANOVA: all groups are equal
- Dunnett's Test: treatments are equal to the controls

Wet weight and dry weight of larvae after 28 days of post-hatch exposure:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: variances are homogenous
- ANOVA: all groups are equal

- The statistical tests were performed using SAS (1979) and Toxstat (Gulley et al., 1989)
- A minimum probability level of 0.05 was used for all tests

Table 1: Fathead Minnow NQ Early Life Stage (ELS) Toxicity Data – Percent Hatch of Embryos after 4 Days of Exposure and Survival of Larvae after 28 Days of Post-hatch Exposure

Conc (mg/l)	Rep	No. of Embryos Exposed	No. of Embryos Lost Because of Fungus	No. of Embryos Hatched	Hatching Success (%)	No. of Larvae that Survived	Larval Survival (%)
Control	1	30	13	17	100	15	88.2
	2	30	13	17	100	11	64.7
380	1	30	0	29	96.7	27	93.1
	2	30	7	23	100	20	87.0
610	1	30	6	22	91.3	22	100.0
	2	30	10	20	100	17	85.0
1050	1	30	11	19	100	15	78.9
	2	30	11	19	100	18	94.7
2030	1	30	10	18	90	15	83.3
	2	30	11	19	100	14	73.7
4040	1	30	3	27	100	0	N/A
	2	30	11	19	100	0	N/A

 

 

 

Table 2: Fathead Minnow NQ Early Life Stage (ELS) Toxicity Data – Total Length (Range), Wet Weight (Range), And Dry Weight (Range) of Fry after 28 Days of Post-hatch Exposure

Conc (mg/l)	Rep	N	Mean Length (mm)	Mean Wet Weight (mg)	Mean Dry Weight (mg)
Control	1	15	16.9 (12.0-22.0)	37.7 (10.0-87.5)	6.7 (2.3-14.5)
	2	11	19.0 (12.0-22.0)	58.6 (11.8-88.9)	11.5 (2.5-18.5)
380	1	27	16.5 (12.5-21.0)	37.4 (12.9-82.6)	6.9 (1.6-17.3)
	2	20	17.7 (12.5-22.0)	45.4 (11.8-84.1)	8.9 (2.5-18.1)
610	1	22	15.8 (11.0-21.0)	30.7 (6.8-85.6)	5.5 (1.3-17.4)
	2	17	17.6 (12.0-22.0)	47.5 (36.8-90.7)	9.9 (1.9-19.9)
1050	1	15	16.5 (12.5-22.0)	36.1 (11.6-90.4)	6.9 (3.2-20.4)
	2	18	16.0 (11.0-24.0)	36.5 (8.8-118.8)	7.2 (2.5-26.1)
2030	1	15	13.4 (10.0-18.0)	17.8 (3.9-51.6)	2.7 (0.2-9.9)
	2	14	12.4 (9.0-16.0)	13.9 (3.5-30.6)	1.9 (0.1-5.8)
4040^a

^a100 % mortality occurred in this treatment group; therefore, the data could not be used for further analysis

Validity criteria fulfilled:

yes

Remarks:

Although this study is conducted in accordance to national standard method the validity criteria according to OECD Guideline 210 are fulfilled.

Conclusions:

The LOEC and NOEC for the fathead minnow during the 28-day ELS test, based on the reduction of total length, were 2030 and 1050 mg/l, respectively. Nitroguanidine was not toxic to fathead minnow during the 28-day ELS.

Executive summary:

The chronic toxicity of Nitroguanidine to early life stage (ELS) of fathead minnow (Pimephales promelas) was studied under flow through conditions. < 12 h old embryos (30 per replicate, two replicates per concentration and control) of fathead minnow were exposed to measured concentrations of 0 (control), 80, 610, 1050, 2030, 4040 mg/l for 4 days. Hatchlings were exposed to the same concentrations for another 28 days. The test system was maintained at 24.9 to 26.0 ºC and a pH of 7.8 to 8.3.

The LOEC and NOEC for the fathead minnow during the 28-day ELS test, based on the reduction of total length, were 2030 and 1050 mg/l, respectively. 

This toxicity study is classified as acceptable and satisfies the guideline requirement for early life toxicity study with fish.

Reference 2

Endpoint:

fish early-life stage toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Goodman, 1986. Proposed new standard guide for conducting early life-stage toxicity tests with fishes. Draft No. 10. American Society for Testing and Materials.

Deviations:

yes

Remarks:

duration of the ELS test was less than that recommended by Goodman (1986).

GLP compliance:

not specified

Specific details on test material used for the study:

Test substance supplier U.S Naval Ordnance Station
Lot No 985-1
Essay 99.998%

Analytical monitoring:

yes

Details on sampling:

- water quality and samples for HPLC measurements were taken daily from alternating replicates of all treatments at time 0 h and every 24 h
- Sample storage conditions before analysis: in the cases samples could not be analysed immediately following filtration, the filtered samples were stored at 4 °C in amber glass vials fitted with Teflon-lined caps and analyzed within 24 h from the time the samples were originally taken from the test aquaria.

Vehicle:

no

Details on test solutions:

PREPARATION OF STOCK SOLUTION:
- saturated stock solutions were prepared by dissolving appropriate amounts of material in aerated diluent water
- stock solutions were stirred in the dark for 24h at room temperature
- occasionally the test material was heated to ~30 °C
- all stock solutions were filtered before use to remove particles > 0.45 µm as well as excess reagent crystals in saturated solutions
- all stock solutions were prepared in amber glass containers
- the highest toxicant concentration tested was the solubility limit of the test material in JHU/APL (John Hopkins University Applied Physics Laboratory) well water at the test temperature

APPLICATION OF STOCK/TEST SOLUTIONS:
- test solutions were delivered by solenoid-activated proportional dilutor systems which were calibrated 24 h prior to the start of a test and checked and/or recalibrated at a minimum twice daily during a test
- the dilutors were constructed of glass; polyethylene fittings and Tygon tubing were also used
- control and test solutions, which were held at the test temperature, were aerated in their respective headboxes (polyethylene or fibreglass tanks) with air supplied by an oil-free compressor
- all stock concentrations were quantified prior to the start of a test, and each time a new stock solution was prepared during the test
- all dilutors were equipped with counters to monitor the cycling rate as well as to ensure proper function of the dilutor
- all stock solutions were kept in the dark to avoid photolysis

- Controls: test solution without NQ

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Source: Pennsylvania Fish Commission, Reynoldsdale Fish Culture Station, New Paris, PA
- Eyed embryos were obtained and were gradually adjusted to JHU/APL (John Hopkins University Applied Physics Laboratory) well water at 12 (+/- 1) °C over a 24-h period and held an additional 24 h prior to testing
- Initial ages of eyed embryos: 14-15 d
- The eyed embroys were in reduced light of < 25 foot candles at the surface of the water
- Embryos were observed at least three times per day during the hatching period
- Recently hatched larvae were released immediatly to the test chambers by lowering the embryo incubation cups below the surface of the test solution


POST-HATCH FEEDING
- Start date: timepoint swim-up occurred in the controls
- Type/source of feed: Salmon Starter Meal
- Amount given: approx. 4 % dry food/wet weight fish
- Frequency of feeding: three times daily on weekdays and twice daily on weekends

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

35 d

Remarks on exposure duration:

7-d embryo exposure and 28-d post-hatch exposure

Post exposure observation period:

None

Hardness:

184 mg/l (as CaCO3)

Test temperature:

12.4 (11.0-13.9) °C

pH:

7.8 (7.5-8.1)

Dissolved oxygen:

9.8 (8.9-10.4)

Salinity:

no data

Nominal and measured concentrations:

- Nominal concentrations: 0, 200, 400, 600, 1000, 1700 mg/l
- Mean measured concentrations: 0, 200, 320, 540, 880, 1520 mg/l

Details on test conditions:

TEST SYSTEM
- Emybro cups (if used, type/material, size, fill volume): glass cylinders (50 mm diameter I.D.; 200 ml volume) fitted with teflon screens
- Test vessel:
- Type: open
- Material, size, fill volume: 10 l glass test chambers with 6.4 l of test solution
- during the embryo incubation periods, the embryos were held in embryo cups constructed of glass cylinders (50 mm diameter I.D.; 200 ml
volume) fitted with teflon screens that were suspended in the 10 l test chambers on a rocker arm apparatus and reciprocated vertically at 2 rpm
to insure good mixing within the embryo cups
- Type of flow-through: proportional diluter
- No. of fertilized eggs/embryos per vessel: 30-40
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Test temperature was maintained by placing the exposure vessel in constant temperature water baths
- Toxicant concentrations were established in the 10 l test chambers 24 h prior to the introduction of the embryos
- recently hatched larvae were released immediatly to the test chambers by lowing the embryo incubation cups below the surface of the test solution allowing the fish to swim free
- any embryos with fungus were removed from the test systems and counted
- embryos removed with fungus were not included in the calculations of hatching success


TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: non-chlorinated deep well located at JHU/APL
- Total organic carbon: 19 mg/l
- Metals: all below L.O.D.
- Pesticides: all below L.O.D.
- Chlorine: not chlorinated
- Alkalinity: 122 mg/l (as CaCO3)
- Conductivity: 242 µmhos/cm
- Intervals of water quality measurement: daily


OTHER TEST CONDITIONS
- Photoperiod: 16 h light / 8 h dark
- Light intensity: < 25 foot candles until swim-up


EFFECT PARAMETERS MEASURED: hatching success, growth and survival


POST-HATCH DETAILS
- Post-hatch fish were observed daily for developmental abnormalities and mortality
- Feeding: Salmon Starter Meal three times daily on weekdays and twice daily on weekends once swim-up occurred in the controls
- Amount of food: approx. 4 % dry food/wet weight fish
- Excess food and feces were siphoned from test chambers at least daily
- At the conclusion of the test, total length, blotted wet weight, and dry weight were determined for a random sample of 20 fish from each treatment
- Dry weight was determined by drying at 60 °C for a minimum of 24 h or longer until a constant weight occurred
- Morphometric data were not taken on fish that died while a test was in progress

Reference substance (positive control):

no

Key result

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

> 1 520 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

number hatched

Remarks on result:

other: embryo exposure

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

> 1 520 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: fry survival, total length, wet weight, dry weight

Remarks on result:

other: post-hatch exposure

Details on results:

- A 7-d exposure to Nitroguanidine at concentrations up to 1520 mg/l did not affect hatching success of the embryos.
- A 28-d post-hatch exposure to concentrations up to 1520 mg/l did not affect fry survival, total length, wet weight, or dry weight.
- A pigmentation was observed at the two highest test concentrations; no other deformities were observed at the lower test concentrations or in the controls.
- For further details see table 1

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

- mean measured concentrations were used in the statistical analyses

Percent hatch of eyed embryos + percent survival of fry:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: data fail to meet the homogeneity of variance assumption
- Kruskal-Wallis Test: all groups are equal

Total length and wet weight of fry after 28 days of post-hatch exposure:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: variances are homogenous
- ANOVA: all groups are equal

Dry weight of fry after 28 days of post-hatch exposure:
- Chi-Square Test for Normality: data are normally distributed
- Bartlett's Test for Homogeneity of Variances: data fail to meet the homogeneity of variance assumption
- ANOVA: all groups are equal

- the statistical tests were performed using SAS (1979) and Toxstat (Gulley et al., 1989)
- a minimum probability level of 0.05 was used for all tests

Table 1: Rainbow Trout NQ Early Life Stage (ELS) Toxicity Data – Percent Hatch of Eyed Embryos after 7 Days of Exposure and Survival of Fry after 28 Days of Post-hatch Exposure

Conc (mg/l)	Rep	No. of Embryos Exposed	No. of Embryos Lost Because of Fungus	No. of Embryos Hatched and Fry Exposed	Hatching Success (%)	No. of Fry that Survived	Fry Survival (%)
Control	1	30	0	30	100	30	100
	2	30	0	29	96.7	29	100
200	1	30	0	30	100	29	96.7
	2	40	0	27	90	25	92.6
320	1	30	0	26	86.7	24	92.3
	2	30	0	28	93.3	25	89.3
540	1	30	0	27	90	27	100
	2	30	0	30	100	30	100
880	1	30	0	29	96.7	27	93.1
	2	30	0	29	96.7	28	96.6
1520	1	30	0	29	96.7	29	100
	2	30	0	26	86.7	26	100

 

Table 2: Rainbow Trout NQ Early Life Stage (ELS) Toxicity Data – Total Length (Range), Wet Weight (Range), And Dry Weight (Range) of Fry after 28 Days of Post-hatch Exposure

Conc (mg/l)	Rep	N	Mean Length (mm)	Mean Wet Weight (mg)	Mean Dry Weight (mg)
Control	1	30	29.3 (27.0-32.0)	206.3 (139.8-284.2)	30.8 (19.3-42.4)
	2	29	29.4 (27.0-33.5)	202.3 (155.6-316.8)	30.5 (21.3-48.3)
200	1	29	29.2 (27.0-32.0)	189.6 (153.0-256.9)	30.0 (21.9-40.5)
	2	25	29.0 (26.0-31.5)	196.7 (126.3-246.9)	30.0 (18.2-38.0)
320	1	24	27.6 (25.0-31.5)	169.8 (98.4-224.3)	26.4 (15.2-36.6)
	2	25	30.1 (28.0-33.5)	224.0 (187.9-282.0)	34.7 (27.3-44.4)
540	1	27	28.8 (26.0-32.0)	191.2 (137.4-320.3)	30.0 (19.6-51.7)
	2	30	28.5 (25.0-30.5)	193.2 (163.5-215.8)	28.6 (9.8-35.7)
880	1	27	28.8 (25.5-31.5)	196.2 (114.6-266.6)	29.1 (16.1-39.7)
	2	28	29.0 (27.5-31.0)	217.5 (172.8-257.2)	32.7 (27.0-38.1)
1520	1	29	27.4 (25.5-29.0)	185.2 (117.5-224.0)	28.7 (18.6-32.5)
	2	26	27.0 (23.0-29.5)	176.5 (110.4-222.8)	27.1 (15.9-33.9)

 

Validity criteria fulfilled:

yes

Remarks:

Although this study is conducted in accordance to national standard method the validity criteria according to OECD Guideline 210 are fulfilled.

Conclusions:

Nitroguanidine was not toxic to rainbow trout during the early life stage (ELS) test at the solubility limit of the compound in water.

Executive summary:

The 35-day chronic toxicity of Nitroguanidine to early life stage (ELS) of Rainbow trout (Oncorhynchus mykiss) was studied under flow through conditions. 14-15 d old eyed embryos (30-40 per replicate, two replicates per concentration and control) of Rainbow trout were exposed to measured concentrations of 0 (control), 200, 320, 540, 880, 1520 mg/l for 7 days. Hatchlings were exposed to the same concentrations for another 28 days. The test system was maintained at 11.0 to 13.9 ºC and a pH o7.5 to 8.1.

The 7-day NOEC for eyed embryos, based on hatching success, was > 1520 mg/l. A 28-d post-hatch exposure to concentrations up to 1520 mg/l did not affect fry survival, total length, wet weight, or dry weight.   

This toxicity study is classified as acceptable and satisfies the guideline requirement for early life toxicity study with fish.

Description of key information

Burton et al., 1993, studied the chronic toxicity of nitroguanidine to early life stage (ELS) of fathead minnow (Pimephales promelas) under flow through conditions. < 12 h old embryos (30 per replicate, two replicates per concentration and control) of fathead minnow were exposed to measured concentrations of 0 (control), 80, 610, 1050, 2030, 4040 mg/L for 4 days. Hatchlings were exposed to the same concentrations for another 28 days. The test system was maintained at 24.9 to 26.0 ºC and a pH of 7.8 to 8.3. In a second test, Burton et al., 1993, examined the 35-day chronic toxicity of nitroguanidine to early life stage (ELS) of Rainbow trout (Oncorhynchus mykiss) was studied under flow through conditions. 14-15d old eyed embryos (30-40 per replicate, two replicates per concentration and control) of Rainbow trout were exposed to measured concentrations of 0 (control), 200, 320, 540, 880, 1520 mg/L for 7 days. Hatchlings were exposed to the same concentrations for another 28 days. The test system was maintained at 11.0 to 13.9 ºC and a pH o7.5 to 8.1.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

NOEC

Effect concentration:

1 050 mg/L

Additional information

The LOEC and NOEC for the fathead minnow during the 28-day ELS test, based on the reduction of total length, were 2030 and 1050 mg/L, respectively. 

The 7-day NOEC for eyed embryos of rainbow trout, based on hatching success, was > 1520 mg/L. A 28-d post-hatch exposure to concentrations up to 1520 mg/L did not affect fry survival, total length, wet weight, or dry weight.   

Nitroguanidine was neither toxic to rainbow trout nor to fathead minnow during the early life stage (ELS) test at the solubility limit of the compound in water.

Table 1: Study synopsis

Guideline Test Type	Species	Effect Concentration (mg/L)	Reference	Reliability
Goodman, 1986. Proposed new standard guide for conducting early life-stage toxicity tests with fishes.Draft No. 10. American Society for Testing and Materials.	1. Oncorhynchus mykiss     2.  Pimephales promelas	NOEC (7d) > 1520 mg/L       LOEC (28d) = 2030 mg/L NOEC (28d) = 1050 mg/L	Burton, D.T.; Turley, S.D.; Peters, G.T.; University of Maryland; 1993	Reliable with restrictions