Carbon black

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Qualifier:

according to guideline

Guideline:

other: DIN 38412, p. 15 and Deutsche Einheitsverfahren zur Wasseruntersuchung (1975)

Deviations:

yes

Remarks:

Incomplete description of dilution water

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Suspensions of the test material at concentrations of 0.025, 0.05, 0.1, 0.2, 0.4, 0.6, and 1.0 g/L were prepared. The solution water was a mixture of chlorine-free drinking water, from Cologne, and deionised water, with a Ca:Mg ratio of 4:1.

Test organisms (species):

Leuciscus idus

Details on test organisms:

Satzfischzucht P. Eggers, Hohenwested. The fish were 5 -6 cm long, and weighed 1.5 +/- 0.3 g

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

no

Hardness:

15 +- 3°d

Test temperature:

20 +- 1°C

pH:

7-8

Dissolved oxygen:

> 6 mg O2/l

Salinity:

not applcable

Nominal and measured concentrations:

nominal

Details on test conditions:

10 fish were tested in each 10 liter vessel with suspensions of the test material. Parts of the substance sedimented on the walls and bottom of the test vessels during the test.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

no signs of toxicity were observed at concentrations up to 1 g/l

Validity criteria fulfilled:

yes

Conclusions:

No signs of toxicity were observed at concentrations up to 1000 mg/L (highest tested dose)

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Dutch standard water (DSW) formulated using Milli-Ro water according to Adema* were used as test medium.
DSW has the following composition:
Ca2* 54.4 mg/l
Mg2+ 17.5 mg/l
Na* 27.4 mg/l
K+ 7.8 mg/l
Cl- 96.6 mg/l
SO4 2- 70.1 mg/l
CO3 2- 210 mg/l
HCO3 84.8 mg/l
Milli-Ro water: Tap-water purified by reverse osmosis (Millipore Corp. , Bedford, Mass., USA)
It should be noted that the DSW was aerated continuously before and during use in the tests which might have changed these values
* Adema D:M:M:, 1980; in: degradability, Eco-toxicity and Bioaccumulation: The determination of the possible effects of chemicals and wastes on the
aquatic environment; Part II, Chapter 5, Government Publishing Office, The Hague, The Netherlands)
The test substance was added quantitatively to DSW providing concentrations of 1000 mg/l. Subsequently, this dispersions of CORAX N220 were
stirred for 70 hours before the exposure started. The final test solutions were turbid, with particles dispersed throughout the medium. Also, a thin
oil-like film was observed on the surface. Although during the exposure period substance deposits were formed in all vessels containing the test
substance, the dispersions remained opaque throughout the 96 hour exposure period.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra-fish (Brachydanio rerio, Teleostei, Cyprinidea
- Strain:
- Source: RASBORA, Veenendaal, The Netherlands
- Age at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD): 3.1 +- 0.21 cm
- Weight at study initiation (mean and range, SD): 0.31 +- 0.05 g
total fish used: 55
- Method of breeding:
- Feeding during test: No feeding from 24 h prior to the test and during the total test period
- Food type:
- Amount:
- Frequency:


ACCLIMATION
- Acclimation period: At least 14 days after delivery
- Acclimation conditions (same as test or not): oxygen concentration, pH, nitrate and nitrite concentration, ammonia concentration and hardness of
the water: once a week. Temperature: every working day
- Type and amount of food: with Trouvit or Artemia
- Feeding frequency: daily
- Health during acclimation (any mortality observed): Following a 48-h settling-in period the fish were allowed to acclimatise for at least seven days.
In the batch of fish used for the test, mortality during the seven days prior to the start of the
test was less than 5%


QUARANTINE (wild caught)
- Duration:
- Health/mortality:

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

no

Hardness:

After aeration the hardness was 210 mg CaCO3 per litre

Test temperature:

The temperature of the test medium measured in the blank control ranged from 20 to 21°C

pH:

The pH ranged from 7.7 to 8.4

Dissolved oxygen:

The oxygen concentration (mg O2/l) at the beginning: 8.0 to 8.8 and at the end of the test: 8.6 to 9.1

Salinity:

not applicable

Nominal and measured concentrations:

nominal concentration: 1000 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: all-glass, 4 litre
- Aeration: continuously
- Renewal rate of test solution (frequency/flow rate): static
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates):
- Biomass loading rate: 0.78 g fish/litre

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h daily
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
At 2.5, 24, 48, 72, 96 h following the start of exposure. Dead fish were removed when observed. During the test it was not possible to record effects on behaviour and appearance in all three vessels containing 1000 mg/l due to the opacity of the test solutions. At the end of the test the fish were
transferred to the control vessel and observed for effects. Fish were considered to be dead when no reaction after touching the caudal peduncle and visible breathing movements were absent. The surviving fish were rapidly killed by exposing them to ca. 1.2% ethylene glycol monophenylethre in
water.

TEST CONCENTRATIONS:
supersaturated dispersion of 1000 mg/l, the maximum concentration to be tested in aquatic toxicity tests
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline: Corax N 220 is insoluble in water
- Range finding study
- Test concentrations: 5 fish per group were exposed to a supersaturated solution of nominally 1000 mg/l or the filtrate of such a solution
- Results used to determine the conditions for the definitive study: limit study, a supersaturated solution of nominally 1000 mg/l

Reference substance (positive control):

yes

Remarks:

pentachlorophenol

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

It was not possible to record effects on behaviour and appearance in these vessels due to the opacity of the test solution.

Results with reference substance (positive control):

The 96h-LC50 of the present test is 0.24 mg/l with 95% confidence interval between 0.19 and 0.34 mg/l. This is in agreement with the historical range of the 96h-LC50 for zebra-fish, this range is betwen 0.2 and 1.0 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present test with CORAX N 220, exposure of fish to supersaturated solutions of nominally 1000 mg/l did not induce any mortality.

Executive summary:

Carbon black was not toxic at nominal concentrations of 1000 mg/l supersaturated suspensions.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Qualifier:

according to guideline

Guideline:

other: DIN 38412 p.15 and Deutsche Einheitsverfahren zur Wasseruntersuchung DEV L15

Deviations:

yes

Remarks:

Filter not described, and test was of only 48 hour duration. Incomplete description of dilution water.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Suspensions of 10 g of the test substance in 1 l of water were filtered. The filtered solution was mixed in ratios of 1/10, <, 2/3, 3/2, and 4/1 with dilution water a mixture of chlorine-free drinking water, from Cologne, and deionised water, with a Ca:Mg ratio of 4:1.

Test organisms (species):

Leuciscus idus melanotus

Details on test organisms:

Satzfischzucht P. Eggers, Hohenwested. The fishs were 5 -6 cm long, and weighed 1.5 +/- 0.3 g

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

15 +- 3°d

Test temperature:

temperature during the test duration: 20 +-1 °C

pH:

pH value during the test duration: 7-8

Dissolved oxygen:

The dissolved oxygen was > 6 mg O2/l during the test duration

Salinity:

not applicable

Details on test conditions:

10 fishs were tested in each 10 liter vessel.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 8 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mortality (fish)

Details on results:

No signs of toxicity observed, in filtrate from up to 8000 mg/l solution

Validity criteria fulfilled:

yes

Conclusions:

No signs of toxicity observed, in filtrate from up to 8000 mg/l solution

Executive summary:

Carbon black is not toxic within its aqueous solubility.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Guideline:

other: DIN 38412,p.15 and Dts. Einheitsverfahren zur Wasseruntersuchung (1975)

Deviations:

yes

Remarks:

Incomplete description of dilution water.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Suspensions of the test material at concentrations of 0.025, 0.05, 0.1, 0.2, 0.4, 0.6, and 1.0 g/L were prepared. The solution water was a mixture of chlorine-free drinking water, from Cologne, and deionised water, with a Ca:Mg ratio of 4:1.

Test organisms (species):

Leuciscus idus melanotus

Details on test organisms:

Satzfischzucht P. Eggers, Hohenwested. The fishs were 5 -6 cm long, and weighed 1.5 +/- 0.3 g

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

15 +-3°d

Test temperature:

the temperature was 20 +-1°C during test duration

pH:

the pH value was 7-8 during the test duration

Dissolved oxygen:

the oxygen concentration was > 6 mgO2/l during the test duration

Salinity:

not applicable

Nominal and measured concentrations:

nominal concentrations

Details on test conditions:

10 fishs were tested in each 10 liter vessel with suspensions of the test material. Parts of the substance sedimented on the walls and bottom of the test vessels during the test.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

No signs of toxicity observed, in filtrate from up to 1g/l test solution

Validity criteria fulfilled:

yes

Conclusions:

No signs of toxicity observed, in filtrate from up to 1g/l test solution

Executive summary:

Carbon black is not toxic within its aqueous solubility

Reference 5

Endpoint:

fish embryo acute toxicity (FET)

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

not reported

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 236 (Fish embryo acute toxicity (FET) test)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

yes

Remarks:

water

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

4-hpf zebrafish embryos

Test type:

not specified

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

4-96 hpf

Details on test conditions:

A group of 4-hpf zebrafish embryos (n=20) was exposed to 120 and 240 mg/L of carbon black (6 mL of test medium in a Petri dish. The exposure period was from 4 to 96 hpf

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 240 mg/L

Nominal / measured:

nominal

Details on results:

The effects on developing zebrafish (Danio rerio) embryos were studied according to OECD TG 236. Dilution water controls were also tested, and embryos were exposed from 4 to 96 hpf (hours post fertilization. The embryos were examined at 24, 48, 52, 56, 72, 75 and 96 hpf. Molecular and cellular analysis showed that the embryonic development of the exposed embryos was not affected. Exposure to 120 or 240 mg/L of carbon black did not induce any hatching delay and did not affect the head–trunk angle of zebrafish embryos both at 24 and 48 hpf or the body length of zebrafish embryos at 48 hpf.

Reported statistics and error estimates:

analysis of variance, p < 0.05

Validity criteria fulfilled:

not specified

Conclusions:

Carbon black did not affect hatching at the concentrations tested. Molecular and cellular analysis showed that the embryonic development of the exposed embryos was not affected.

Executive summary:

The effects on developing zebrafish (Danio rerio) embryos were studied according to OECD TG 236. Dilution water controls were also tested, and embryos were exposed from 4 to 96 hpf (hours post fertilization). The embryos were examined at 24, 48, 52, 56, 72, 75 and 96 hpf. Molecular and cellular analysis showed that the embryonic development of the exposed embryos was not affected. Exposure to 120 or 240 mg/L of carbon black did not induce any hatching delay and did not affect the head–trunk angle of zebrafish embryos both at 24 and 48 hpf or the body length of zebrafish embryos at 48 hpf.

Description of key information

In several high-quality acute toxicity tests with different carbon black nanoforms (with no surface treatment), exact acute toxicity values could not be achieved because carbon black is highly insoluble in water and organic solvents. In all of these studies the No Effect Concentrations (NOECs) were equal to the highest test concentrations, usually 1000 mg/L. LC 50 is thus above 1000 mg/ m3. No signs of toxicity were noted.