Succinonitrile

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:

2016

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)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: DSM Engineering Plastics B.V. lotnumber SN0620140520
- Expiration date of the lot/batch: 2016.07.01
- Purity test date: 99.93%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Store in a cool area (IO-20°C). Containers that have been opened must be filled with dry nitrogen for at least 1min and then sealed. Be careful not to import any water or impurities during the filling and sealing course.
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: Easily soluble in cold water


FORM AS APPLIED IN THE TEST white waxy solid

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

other: Rare Minnow (Gobiocypris rams)

Details on test organisms:

TEST ORGANISM
- Common name: Rare Minnow (Gobiocypris rams)
- Strain: The batch of brood stock was Rare Minnow 20140522
- Source: Institute of Hydrobiology, Chinese Academy of Sciences.
- Feeding during test yes
- Food type: brine shrimp nauplii (BSN) or frozen brine shrimp (FBS) twice on
weekday and one time on weekend.

Test type:

semi-static

Water media type:

not specified

Limit test:

yes

Total exposure duration:

28 d

Test temperature:

25 +/-: 2 °C;

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

> 10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Physicochemical measurements and test conditions measurement in the definitive test

The results of pH value and dissolved oxygen are shown in Section 15 Table 1. The determined results of pH value were 7.46-7.95, dissolved oxygen were 75.9—104.0% of air saturation value (ASV). Dissolved oxygen was in the allowed range of >60% of ASV. The hardness of test water was 136 and 142 mg/L (as CaCO3). During the test, a majority of temperatures were in range of 23.00~26.06°C, except that 14 temperature data exceeded the lower limit of test temperature 23°C, the values

were in the range of 22.47~22.98°C, the whole temperature difference was 359°C. The deviation of temperature has been evaluated in section 12 and did not affect the quality or integrity of the study.

13.2 Results of observations in the definitive test

During the exposure period, no abnormal appearance or behaviour were observed in the control and test groups for embryos and juvenile fish.

The hatching, observations of appearance or behaviour, mortality, weights and lengths are presented in Section 15 Table 2 to 7.

The reSults showed that days to begin of hatch, 90% hatching and end of hatching, hatching rate and Survival rate of post-hatch success, the dry weights and individual total lengths have no significant difference (p>0.05) between the control and test group.

13.3 Verification of Test Concentration in the definitive test

The concentrations of test item were determined in samples of test media by GC method. The results showed that the mean measured concentration of Succinonitrile in the freshly prepared solutions were 79.2% of the nominal concentration, the mean

measured concentration in expired test solutions were 92.0% of the initial measured

concentration. The geometric mean of the measured concentrations in test media was

7.56 rug/L, which were 75.6% of the nominal concentration. The results are shown in

APPENDIX 2 Table 5.

Validity criteria fulfilled:

yes

Conclusions:

According to the results, under the test conditions of our facility, NOEC (No Observed Effect Concentration) of Succinonitrile Fish, Early-life Stage Toxicity Test to Rare Minnow (Gobiocyprz’s rams) in endpoints including days to begin of hatch, 90% hatching and end of hatching, hatching rate and survival rate of post-hatch success, the dry weights and individual total lengths was larger than 10 mg/L (nominal).

Executive summary:

Fish, Early-life Stage Toxicity Test of Succinonitrile was conducted with Rare Minnow (Gobiocypris rams) in our facility.

Based on the results of a preliminary test, the definitive test was conducted at the limit concentration of 10 mg/L, concurrently with a blank control group. 80 fertilised eggs were used for test concentration and control and divided equally between 4 replicate test chambers.

The test was performed with renewal of the test solutions every Monday, Wednesday, Friday. The test organisms were retained in the beakers whilst 4/5 of test solution/control volume was changed. During the test, the dissolved oxygen and pH values were measured at the start, weekly and at the end of the test in all test vessels before and after test solution renewal. Total hardness was measured in control solution at the beginning and end of the test. Temperature was monitored continuously and recorded at 1 hour interval by automatic temperature monitoring system.

During the exposure period, observations on hatching and survival were made one time on 3 hours after exposure and then daily and the number were recorded. For embryos, larvae and juvenile fish, there were no obvious abnormal appearance or behaviour observed in the test and control groups. The dry weights on a replicate basis and individual total lengths were measured at the end of the test.

Days to begin of hatch, 90% hatching and end of hatching, hatching rate and survival rate of post~hatch success, the dry weights on a replicate basis and individual total lengths in test and control groups were calculated. The data were used for statistical analysis using Two-sided Student t-test with a 5% significance level. According to the results, days to begin of hatch, 90% hatching and end of hatching,

hatching rate and survival rate of post-hatch success, the dry weights and individual total lengths have no significant difference (p>0.05) between the control and test group.

The concentrations of test item were determined in samples of test media by GC method. A sample was pretreated and analysed fiom test concentration and control

during the definitive test (freshly prepared media on 0, 9, 16, 21 and 28 day after exposure, and expired media on 2, 12, 19, 23 and 30 day after exposure). The results

showed that the mean measured concentration of Succinonitrile in the freshly prepared solutions were 79.2% ofthe nominal concentration, the mean measured concentration in

expired test solutions were 92.0% of the initial measured concentration. The geometric mean of the measured concentrations in test media was 7.56 mg/L, which were 75.6%

of the nominal concentration.

According to the results, under the test conditions of our facility, NOEC (No Observed Effect Concentration) of Succinonitrile Fish, Early-life Stage Toxicity Test to Rare Minnow (Gobiocyprz’s rams) in endpoints including days to begin of hatch, 90% hatching and end of hatching, hatching rate and survival rate of post-hatch success, the dry weights and individual total lengths was larger than 10 mg/L (nominal).

Description of key information

NOEC is > 10 mg/l