Chlorpyrifos

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:

supporting 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

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Substance ID: Chlorpyrifos
Lot#: KC28161419 (TSN 101285)
Purity: 99.8%

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

Dimethylformamide containing 10% Tween 20

Test organisms (species):

Cyprinus carpio

Test type:

flow-through

Water media type:

other: Well water

Total exposure duration:

96 h

Hardness:

40 mg/L as CaCO3

Test temperature:

21 - 23°C

pH:

6.5 - 7.0

Dissolved oxygen:

8.1 - 9.3 mg/L

Conductivity:

120 - 130 µmhos/cm

Nominal and measured concentrations:

Nominal: 0.041, 0.091, 0.20, 0.45, 1.0 mg/L
Measured: 0.035, 0.082, 0.19, 0.42, 0.96 mg/L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.19 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: Corresponding 95% confidence intervals was 0.11 to 0.33 mg/L

Remarks:

LC50 and 95% confidence intervals calculated by probit analysis.

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

< 0.035 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

< 0.035 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

> 0.96 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Key result

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

0.29 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence intervals: 0.14 - 0.86 mg/L

Remarks:

LC50 and 95% confidence intervals calculated by probit analysis.

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

0.29 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval: 0.14 - 0.86 mg/L

Remarks:

LC50 and 95% confidence intervals calculated by probit analysis.

Key result

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 0.96 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

act. ingr.

Basis for effect:

mortality (fish)

Remarks on result:

other: LC50 value was empirically estimated.

Validity criteria fulfilled:

yes

Conclusions:

96 hr LC50 (Common carp): 0.19 mg/L (Based on mortality)
96 Hr NOEC (Common carp): <0.035 mg/L (Based on mortality)

Executive summary:

The study was conducted according to guideline OECD 203 to to determine the toxicity of test substance based on the results (LC50) of a 96-hour flow-through acute toxicity test using a representative freshwater fish species, the carp (Cyprinus carpio). The nominal concentrations of test substance tested were 0.041, 0.091, 0.20, 0.45, 1.0 mg/L and mean concentrations of test substance tested were 0.035, 0.082, 0.19, 0.42, 0.96 mg/L.

The 96-hour LC50 and corresponding 95% confidence intervals for carp (Cyprinus carpio) was calculated by probit analysis to be 0.19 mg a.i./L (0.11 to 0.33 mg a.i./L). The highest concentration producing 0% mortality was <0.035 mg a.i./L The lowest concentration producing 100% mortality was >0.96 mg a.i./L. The No-Observed-Effect Concentration (NOEC) was determined to be <0.035 mg a.i./L.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Substance Id: Chlorpyrifos
Purity: Not reported; Known to sponsor

Analytical monitoring:

no

Remarks:

No analysis was done to confirm the concentrations but the test media was renewed on a daily basis.

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

A 0.56% w/v solution in acetone was further diluted with acetone to give a series of solvent stock solutions of 10e4 times final concentration. These were dispensed at a uniform rate of 100 µL/L to give the test solutions.

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: Ide
- Strain: Leusiscus idus
- Source: Humberside Fisheries, West Yorkshire

ACCLIMATION
- Acclimation period: acclimatised to test conditions from 25 April to 1 May 1985
- Type and amount of food during acclimation: Commercial trout pellet, Discontinued 24 h prior to test
- Health during acclimation (any mortality observed): 2%

Test type:

semi-static

Water media type:

freshwater

Total exposure duration:

96 h

Hardness:

320 mg/L

Test temperature:

13 ± 1°C

pH:

8.0-8.3

Dissolved oxygen:

>10 mg/L

Nominal and measured concentrations:

0.0032, 0.0056, 0.010, 0.018, 0.032, 0.056 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass aquaria holding 40 L of test media.
- No. of organisms per vessel: 10 animals per test concentration
- Biomass loading rate: 1.4 g bodyweight/L
- Aeration: Via narrow bore glass tubes
- Medium Renewal: Daily

TEST MEDIUM / WATER PARAMETERS : not reported

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light 8 h dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Absence of respiratory movement and response to physical stimulation.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.01 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Key result

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

0.013 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

0.015 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Key result

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

0.021 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

96-hr LC50 (Leusiscus idus): 0.010 mg/L (Based on mortality)

Executive summary:

The study was conducted according to guideline OECD 203 to evaluate acute aquatic toxicity in fish in semi-static conditions. Ide (Leuciscus idus) were exposed to test substance at concentrations of 0.0032, 0.0056, 0.010, 0.018, 0.032, 0.056 mg/L. Based on the mortality the 96 -Hr LC50 value was 0.010 mg/L.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting 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

Specific details on test material used for the study:

Substance ID: Chlorpyrifos
Lot#: Not reported
Purity: Not reported

Analytical monitoring:

no

Vehicle:

yes

Remarks:

Acetone

Test organisms (species):

Rutilus rutilus

Test type:

semi-static

Water media type:

other: Dechlorinated laboratory tap water

Total exposure duration:

96 h

Hardness:

320 mg/L

Test temperature:

13 ± 1°C

pH:

7.9 - 8.1

Dissolved oxygen:

9.0 - 11 mg/L

Nominal and measured concentrations:

0.032, 0.056, 0.10, 0.18, 0.32, 0.56 mg/L

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.25 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence limits (mg/L) of test substance LC 50 was 0.17 - 0.36

Key result

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

0.34 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence limits (mg/L) of test substance LC 50 was 0.19 - 0.59

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

> 0.56 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Key result

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 0.56 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

> 0.56 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

96 Hr LC50 (Roach): 0.25 mg/L (Based on mortality)

Executive summary:

The study was conducted according to guideline OECD 203 to determine the acute toxicity of test substance to roach in semi-static conditions.

No analysis was done to confirm the concentrations but the test media was renewed on a daily basis. The 96 hr LC₅₀to roach was found to be 0.25 mg/L (95% limits 0.17 - 0.36).

Description of key information

96 -hour LC₅₀ ( Leusiscus idus, Ide): 0.010 mg/L; OECD 203, Reliability = 1

96 -hour LC₅₀ ( Rutilus rutilus, Roach): 0.25 mg/L; OECD 203, Reliability = 1

96 -hour LC₅₀ ( Cyprinus carpio, Common carp): 0.19 mg/L; OECD 203, EU Method C.1, Reliability = 1

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.01 mg/L

Additional information

The test substance was tested in 3 freshwater species. Acute 96 -hour LC₅₀ values in freshwater species ranged from 0.010 mg/L to 0.25 mg/L.