Bis(2,4-dichlorobenzoyl) peroxide

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1989-12-8 to 1990-01-27

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test was done under GLP and well performed and documented. Howeverthe test substance remained visible during the test.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Due to the poor solubility of the test substance, acetone. as an organic solvent was used. However, the test substance did not dissolve and remained visible as a clot. Therefore, no acetone was used in the definitive test.
The test concentration was prepared by direct addition of 1000 mg of test substance/I diluting water. The test media were stirred for 24 hours to reach an equilibrium in water. After this time and during the test the test substance remained visible at the bottom of the test vessel as a clot.

Test organisms (species):

Poecilia reticulata

Details on test organisms:

The test organism was Poecilia reticulata (guppy).
In contravention to the study plan they were obtained from a well-known local aquarium retailer. The fish were held in stock for 13 days in the Akzo Research Laboratories Arnhem, dept. CRL, according to Standard Operating Procedures SOP CRL T9 and 42 to determine the acceptability of the batch. The size of the fish was approximately 2 cm.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

13 dH

Test temperature:

25-26 C

pH:

8.0-8.2

Dissolved oxygen:

7.1-8.2 mg/L

Nominal and measured concentrations:

1000 mg/L nominal

Details on test conditions:

In contravention to the study plan the temperature was kept between 25°C and 26°C and the light regime was 12 hours of ambient light per day. The duration of the test was 96 hours. As test vessels were used 2 L covered glass aquaria which con~
tained 1 L of test medium. The loading of the test vessels was approximately 0.6 g biomass/I. The surviving fish were counted daily and dead fish removed immediately upon observation. Oxygen concentration measurements were carried out on days 2 and 4, pH-measurements on days 0, 2 and 4. If a high mortality was observed on the other days, the oxygen concentration and pH were measured then also.

Reference substance (positive control):

no

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)

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)

Details on results:

The fish survived for 96 hours in dilution water which contained 1000 1119' Bis (2, 4-dichlorobenzoyl) peroxide. Binomial theory dictates that when 10 fish are used showing 0% mortality, there is a 99.9% confidence that the LC50 is greater than 1000 1119'/l. However, given that the test substance remained visible during the test, the LC50. should be handled with care.
No other effects, such as deviations in the behaviour or appearance of the fish could be determined. The quality criteria of this test have been fulfilled: the mortality in the control was ~lO% and the oxygen concentration was >60% of the air saturation value throughout the test (in earlier tests the air saturation value was d.etermined to be approximately 8.5 1119' °2/1).
Considering the results of a biodegradability study (C.G. van Ginkel, 1990: Biodegradability of Bis (2,4-dichlorobenzoyl)
peroxide) , it is likely that the test substance concentration remained constant during the test.

Reported statistics and error estimates:

Binomial theory dictates that when 10 fish are used showing 0% mortality, there is a 99.9% confidence that the LC50 is greater than 1000 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

Study is valid, done under GLP, the LC50 was determined based on nominal concentration to be >1000mg/L, the NOEC = 1000 mg/L. However, given that the test substance remained visible during the test, the LC50. should be handled with care.

Executive summary:

Bis ( 2 , 4-dichlorobenzoyl) peroxide was tested in an acute toxicity test with Poecilia reticulata (guppy) under semi-static conditions in accordance with EEC method C.1.(1984) and OECD Test Guideline 203 (1984). The test was performed in duplicate. The fish survived for 96 hours in diluting water containing 1000 mg of test substance per litre. Binomial theory dictates that when 10 fish

are used showing 0% mortality, there is a 99.9% confidence that the LC50 (96 h) is greater than 1000 mg/L However, given that the test substance remained visible as a clot at the bottom of the test vessel, the LC50 should be handled with care. No other effects, such as deviations in the behaviour or appearance of the fish could be observed.

Description of key information

One OECD 203 test with Poecilia reticulata  is available where the EC50 > 1000 mg/L (loading rate)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

1 000 mg/L

Additional information

Bis (2,4-dichlorobenzoyl) peroxide was tested in an acute toxicity test with Poecilia reticulata (guppy) under semi-static conditions in accordance with EEC method C.1.(1984) and OECD Test Guideline 203 (1984). The test was performed in duplicate. The fish survived for 96 hours in diluting water containing 1000 mg of test substance per litre. However, given the low solubility of this substance, and the presence of some undissolved particles, the test substance is considered not harmful to fish even at very high concentrations. This is also supported by the absence of any observable effects or deviations in the behaviour or appearance of the fish.