5-bromo-1,3-dichloro-2-fluorobenzene

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Remarks:

The study was conducted to meet the national regulatory requirements in a non-EEA country.

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

SEPA, P.R. China, the Guidelines of Chemical Testing Good Laboratory Practices (HJ/T 155-2004), China is not a member of OECD and hence there is no agreement on mutual acceptance of data

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

2012

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

SEPA, P.R. China, the Guidelines of Chemical Testing Good Laboratory Practices (HJ/T 155-2004), China is not a member of OECD and hence there is no agreement on mutual acceptance of data

Analytical monitoring:

yes

Details on sampling:

The concentrations of the test substance in test media were analysed once a week in fresh and old media (i.e. analyses were made on a sample from the same solution when freshly prepared and at renewal) on days 1 and 2, days 11 and 12 and days 18 and 19.

Vehicle:

no

Details on test solutions:

A stock solution of 5 mg/L was prepared before the start of the test and at each daily renewal. 0.05 to 0.0505 g test material was weighed and added to glass bottles filled with 10 L of test water. The bottles were capped and the solution was mixed by magnetic stirring for 24 to 25 hours and allowed to stand for 30 to 60 minutes. Appropriate volumes of the stock solution were then removed from the mixture at 10 cm above the bottom by using a pipette to prepare the dilutions. The nominal test concentrations were obtained by diluting the stock solution, applying a spacing factor of 1.78.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: Straus
- Age at study initiation (mean and range, SD): less than 24 hours, not first brood
- Method of breeding: test animals were derived from a healthy, pre-cultured population (i.e. showing no signs of stress such as high mortality, presence of males or ephippia, delay in the production of first brood, discoloured animals); the pre-cultured animals were maintained in culture conditions (light, temperature, medium) similar to those to be used in the test
- Source: originally obtained from Applying Chemistry Department Pesticide Environmental Evaluation Laboratory of China Agricultural University
- Feeding during test: the diet of parental animals was living algal cells of Chlorella sp. and Desmodesmus subspicatus, which was fed as a concentrated suspension. The diet was given based on the amount of organic carbon provided to each animal and was between 0.1 and 0.2 mg C/daphnid/day. The actual feeding amount was at the level of 0.1 mg C/daphnia/day on days 0-8 and 0.15 mg C/daphnia/day thereafter.

ACCLIMATION
Not required

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

160 to 170 mg/L as CaCO3

Test temperature:

19.4 to 20.5 °C

pH:

7.73 to 8.14

Dissolved oxygen:

8.86 to 9.23 mg/L

Salinity:

not reported

Conductivity:

not reported

Nominal and measured concentrations:

Nominal concentrations: 0.1, 0.18, 0.32, 0.56 and 1.0 mg/L
Geometric means measured concentrations: 0.0133, 0.0185, 0.025, 0.0394 and 0.082 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: all
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 200 mL glass beakers, containing about 90 mL of test medium
- Aeration: before use, the water was aerated for 24 hours
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: one
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates): not applicable

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water treated with Aqupro Pure Water System
- Total organic carbon: <2 mg/L
- Suspended solids: <5 mg/L
- pH measured: 7.6
- Limits established for several pesticides, heavy metals and organic molecules were all respected
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light, 8 hours darkness
- Light intensity: 1000 - 1500 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): appearance of first brood, offspring production per day, total number of broods, mortality, body length

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.78
- Range finding study
- Test concentrations: 0.01, 0.04, 0.2, 1 and 5 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.018 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mortality: Number of living offspring produced per surviving parental animal {for Daphnia magna, TG 211}

Key result

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

0.022 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mortality: Number of living offspring produced per surviving parental animal {for Daphnia magna, TG 211}

Key result

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

0.025 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mortality: Number of living offspring produced per surviving parental animal {for Daphnia magna, TG 211}

Details on results:

During the test no immobilisation or mortality of parental animals was observed in the controls, and at 0.0133, 0.0185, 0.025, 0.0394 mg/L. All parental animals at the highest test concentration of 0.082 mg/L died between day 13 and 15 of the study. Total living offspring displayed significant statistical difference between the control and the test concentrations of 0.025, 0.0394 and 0.082 mg/L. The time of production of first brood was statistically significantly different from the control at the higest test concentration of 0.082 mg/L. The number of total brood per each parent was statistically different at the test concentrations of 0.0394 and 0.082 mg/L. And the body length of parental animals was statistically significantly different from controls in the group exposed to 0.0394 mg/L.

Reported statistics and error estimates:

Two-sided Student t-test using a 5% significance level was used for the statistical analysis.

Validity criteria fulfilled:

yes

Conclusions:

The substance exhibit adverse effects on aquatic invertebrates in the chronic daphnia reproduction toxicity test. The total number of living offspring for each parental animal was the most sensitive endpoint, and the following effects levels were determined over the period of 21 days (based on geometric mean measured concentrations): NOEC = 0.0185 mg/L, LOEC = 0.025 mg/L, EC10 = 0.0223 mg/L, EC20 = 0.0268 mg/L.

Executive summary:

The long-term toxicity of the substance to aquatic invertebrates (Daphnia magna) was studied under semi-static conditions in the daphnia reproduction toxicity test for a period of 21 days in accordance with OECD TG 211 under Chinese GLP. Based on the results of a preliminary test, the definitive test was conducted with five nominal test concentrations of 0.1, 0.18, 0.32, 0.56 and 1.0 mg/L, with a concurrent control group. Ten animals were individually held at each test concentration in 200 mL glass beakers filled with approximately 90 mL test medium per vessel. Test media were exchanged daily. The hardness was measured in the control solutions once a week (160 to 170 mg/L as CaCO3), the pH value (7.73 to 8.14) and the dissolved oxygen (8.86 to 9.23 mg/L in fresh and old test media of all test concentrations and the control was determined once a week, the light intensity was determined at the beginning and the end of the test (1157 to 1382 lux), and the test temperature was monitored continuously (19.4 to 20.5 °C). The concentrations of the test substance in test media were analysed once a week in fresh and old media (i.e. analyses were made on a sample from the same solution when freshly prepared and at renewal), and it was found that the concentrations of the test substance in old test media decreased significantly over a period of 24 hours. Therefore, the mean exposure concentrations over the whole test period were calculated from the geometric mean measured concentrations of each renewal period: 0, 0.0133, 0.0185, 0.025, 0.0394 and 0.082 mg/L. The results were all based on these geometric mean measured concentrations. The total number of living offspring per parental animal was the most sensitive endpoint in this study, and the following values were determined: 21-day NOEC = 0.0185 mg/L, 21-day LOEC = 0.025 mg/L, 21-day EC10 = 0.0223 mg/L, 21-day EC20 = 0.0268 mg/L. Furthermore the following other endpoints were determined: mortality of parental animals had a NOEC of 0.0394 mg/L, time to production of first brood had a NOEC of 0.0394 mg/L, total number of broods per partental animal had a NOEC of 0.025 mg/L and body length of living parental animals had a NOEC of 0.025 mg/L.

Description of key information

21-day EC10 = 0.0223 mg/L, 21-day NOEC = 0.0185 mg/L (based on total number of living offspring per parental animal), Aquatic invertebrates (Daphnia magna) reproduction toxicity test, semi-static (China GLP, OECD TG 211)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.022 mg/L