Reaction mass of 1,3-diisopropylbenzene and 1,4-diisopropylbenzene

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:

weight of evidence

Study period:

1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

One exposure concentration at the solubility of the TS

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Temperature, pH, and dissolved oxygen were analyzed at 0, 24, 48, 72, and 96 hours.
Test material concentration was assessed at 0, 48, and 96 hours.

Vehicle:

no

Details on test solutions:

Separate tests indicated that the test substance exhibited low solu bility and high volatility in water. One gram of the test substance was introduced into an elutriation column and 20 liters of dilution water was continuously circulated through the test chamber and column at a rate of 100 mL/minute in order to maintain exposure concentrations at or near the solubility level throughout the test. Test substance equilibrium was achieved before introducing test organisms and maintained during the exposure (0.86-0.96 mg/L at 0, 48, 96 hours).

Test organisms (species):

Pimephales promelas

Test type:

other: Static w/ recirculating elutriation system

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

131 ppm

Test temperature:

20-21°C

pH:

ranged from 8.0-8.3

Dissolved oxygen:

7.1-8.0 mg/L

Nominal and measured concentrations:

Nominal: 50 mg/L
Test solution was maintained at a saturating level through a recirculating elutriation system: 0.91 mg/L (Average of the two replicate means)

Details on test conditions:

Study was conducted in duplicate using 10 fish per tank with loading kept below 0.5 g/L. The lighting regimen consisted of 16 hours on and 8 hours off with a 20minute transition period.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.91 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Average of the two replicate means

Details on results:

All fish exhibited normal behavior.

Reported statistics and error estimates:

NA, There were no deaths noted.

Validity criteria fulfilled:

yes

Conclusions:

No effects were seen at the solubility limit of the test substance.

Executive summary:

m-DIPB was tested for acute toxicity towards Pimephales promelas for 96H in a methodology equivalent to OECD 203 guideline and following GLP. The test was conducted using a flow-through, recirculating elutriation system designed to expose the organisms to an exposure concentration at or near the solubility of the test substance. Results of an unpublished 96-hour volatility study on m-DIPB indicated that the substance is extremely volatile in water with 100% of the material lost over 96-hours from a 1.9 mg/L solution. Therefore, the measured concentration of m-DIPB (0.91 mg/L) was the result of the low solubility and high volatility of the test substance, but reflected the most effective experimental flow-through design to maximize the exposure concentration. All fish exhibited normal behavior and it can be stated that m-DIPB is not toxic to fish at solubility limit.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

One exposure concentration at the solubility of the TS

GLP compliance:

no

Analytical monitoring:

not specified

Vehicle:

no

Details on test solutions:

Due to low solubility of the test substance, 2.3 grams of the test substance was introduced into an elutriation column and 23 liters of dilution water was continuously circulated through the test chamber and column at a rate of 100 mL/minute in order to maintain exposure concentrations at or near the solubility level throughout the test.Test substance equilibrium was achieved before introducing test organisms and maintained during the exposure.

Test organisms (species):

Pimephales promelas

Test type:

other: Static w/ recirculating elutriation system

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Nominal and measured concentrations:

Nominal: 100 mg/L (concentration assumed to reach equilibrium at the limit of solubility)

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 3 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 3 mg/L was found to be the limit of solubility of the TS

Details on results:

All fish exhibited normal behavior.

Reported statistics and error estimates:

NA, There were no deaths noted.

Conclusions:

No effects were seen at the solubility limit of the test substance.

Executive summary:

p-DIPB was tested for acute toxicity towards Pimephales promelas for 96H in a methodology equivalent to OECD 203 guideline. The test was conducted using a flow-through, recirculating elutriation system designed to expose the organisms to an exposure concentration at or near the solubility of the test substance. This test system reflected the most effective experimental flow-through design to maximize the exposure concentration. All fish exhibited normal behavior and it can be stated that p-DIPB is not toxic to fish at solubility limit.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

See attached document in section 13 "Assessment reports" for justification and rationale of the analogy approach.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.91 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: which is considered to be the maximum reachable concentration considering the low solubility and the high volatility of the substances.

Validity criteria fulfilled:

yes

Conclusions:

Based on the analogy approach, the target substance and source substances are expected to have same behavior in aquatic compartment. Hence, the LC50 values were derived for the DIPB mixture of isomers from experimental results on the souce substances m-DIPB and p-DIPB. The 96H-LC50 for the target substance was determined to be above 0.91 mg/L, which is considered to be the maximum reachable concentration considering the low solubility and the high volatility of the substances.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted according to guideline (literature not available), the data, however, were evaluated in the frame of the OECD SIDS program and therefore regarded as valid

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

a) Dilution Water Source: Tap water (Yokohama city, Kanagawa, Japan) dechlorinated using activated carbon. After that Residual Chlorine was removed from the water by aeration.
b) Exposure Vessel Type: 5 L test solution in a 5 L glass tank with a teflon cover sheet to prevent loss of test substance
c) Nominal Concentrations: control, solvent control,0.200, 0.360, 0.630, 1.10 and 2.00 mg/L
d) Stock Solution: 100 mg test substance was dissolved in pure water of 100 mL with vehicles (DMF 3g + HCO60 2g).
e) Vehicle/Solvent and Concentrations: Dimethyl formamide and HCO-40 were used for solvent in test water except the control. The concentration of Dimethyl formamide and HCO-40 in the test solutions was 60 mg/L and 40 mg/L at the maximum, respectively.

Test organisms (species):

Oryzias latipes

Details on test organisms:

a) Supplier: Test organisms were obtained from Sankyo Suisan (Private Fish Farm,Tokyo Japan).
b) Size (length and weight): 1.88cm (1.64 - 2.11 cm, n = 10) in length; 0.099 g (0.074 - 0.122 g, n = 10) in weight
c) Age: Not described
d) Any pretreatment: Test organisms were acclimated for at least 17 days before testing.
Any groups showing > 5 % mortality for 7 days before testing were not used for testing. During acclimination, test fish were fed with TETRAMINE equivalent to 2% of weight. These test organisms were not fed for 24 hours before the test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

Total hardness (as CaCO3): = 60 mg/L

Test temperature:

Water Temperature: 24+/-1 degrees C

pH:

pH: = 7.6

Nominal and measured concentrations:

-Analytical Procedure: Test substance in each test solution were measured at the start and every 24h hour (before exchange of test solution), using HPLC with detection limit of 0.002 mg/L.

Details on test conditions:

a) Number of Replicates: 1
b) Fish per Replicates: 10
c) Renewal Rate of Test Water: Every 24 hours
d) Water Temperature: 24+/-1 degrees C
e) Light Condition: 16:8 hours, light-darkness cycle
f) Feeding: None
g) Aeration : Not described

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

1.48 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.707 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 0.539-0.935 mg/L

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

0.25 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Reported statistics and error estimates:

a) Data Analysis: Probit method, binomial or Moving average for LC50
b) Method of Calculating Mean Measured Concentrations (i.e. arithmetic mean, geometric mean, etc.): Geometric mean

Sublethal observations / clinical signs:

Cumulative Mortality: None of test organisms were killed during exposure period at solvent control, 0.200 and 0.360 mg/L, however, all test organisms were killed at 2.00 mg/L on and after 72 hours. Although at the end of test in the control 1 test fish was killed, the mortality did not exceed 10%. Therefore the test was valid acc. to OECD test guideline. The lowest concentration that the test organisms were killed was 0.630 mg/L after 72 hours.

---------------------------------------------------------
Cumulative Number of Dead
Nominal (Percent Mortality)
Conc. Mean* ---------------------------------------
mg/L mg/L 24hr 48hr 72hr 96hr
---------------------------------------------------------
Control --- 0 (0) 0 (0) 0 (0) 1 (10)
Solvent
Control --- 0 (0) 0 (0) 0 (0) 0 (0)
0.200 0.137 0 (0) 0 (0) 0 (0) 0 (0)
0.360 0.250 0 (0) 0 (0) 0 (0) 0 (0)
0.630 0.431 0 (0) 0 (0) 1 (10) 2 (20)
1.10 0.816 0 (0) 2 (20) 2 (20) 5 (50)
2.00 1.48 3 (30) 9 (90) 10 (100) 10(100)
---------------------------------------------------------
*: Mean measured concentration (Geometric Mean)


Water chemistry (pH and DO) and temperature in test:
Water chemistry and temperature were measured for old and renewal solution with control and each concentration at the start of test and every 24 hours.
pH: 7.2 - 7.8
DO: 5.8 - 8.4 mg/L
Water Temperature: 24+/-1 degrees C

Effect Data (mortality):
LC50 (96hr) = 0.707 mg/L (95% C. I.: 0.539-0.935) (mc)
LC0 (96hr) = 0.250 mg/L (mc)
LC100 (96hr) = 1.48 mg/L (mc)
mc: based on measured concentration

Measured Concentrations : The test concentrations were measured at the start and 24th hour (before exchange of test solution). For some of them, the deviation from the nominal concentration were not less than +/- 20% of nominal concentration.
----------------------------------------------------------
Nominal Measured Conc., mg/L Percent of Conc. Nominal mg/L ------------------- ------------
0 hr 24 hr Mean* 0 hr 24 hr
Fresh Old mg/L Fresh Old
---------------------------------------------------------
Control <0.002 <0.002 --- --- ---
Solvent Control <0.002 <0.002 --- --- ---
0.200 0.168 0.111 0.137 84 56
0.360 0.298 0.209 0.250 83 58
0.630 0.526 0.353 0.431 83 56
1.10 0.942 0.706 0.816 86 69
2.00 1.73 1.26 1.48 87 63
---------------------------------------------------------
*: Mean measured concentration (Geometric Mean)
Fresh: Start of renewal period
Old: End of renewal period

Other Effect: Toxicological symptom was first observed at 0.630 mg/L (24 hour ).

--------------------------------------------------------
Nominal Symptoms
Conc. Mean*--------------------------------
mg/L mg/L 24hr 48hr 72hr 96hr
--------------------------------------------------------
Control ---- n n n n
Solvent Control ---- n n n n
0.200 0.137 n n n n
0.360 0.250 n n n n
0.630 0.431 as-2 as-5 as-5 as-8
1.10 0.816 as-10 as-8 as-1 as-8
ap-7 ap-4
2.00 1.48 as-7 ap-1 -- --
--------------------------------------------------------
*: Mean measured concentration (geometric mean)
n: No abnormalities are detected
as: abnormal swimming
ap: paralyzation
--: All fishes were dead at this observation time.

Calculation of toxic values: It was the mean measured concentrations. The reason is that some of the error ranges of measured concentration were not less than +/-20% of nominal concentration.

Validity criteria fulfilled:

no

Remarks:

All toxic signs above water solubility limits

Conclusions:

In a study conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test), Oryzias latipes were exposed to diisopropylbenzene concentrations for 96 h. The test was conducted using dispersant, and the estimated values were higher than water solubility, however, analytical monitoring was done. A 96 h LC50=0.707 mg/L (95% C.L.: 0.539 -0.935 mg/L; measured concentrations) was determined. However, all toxic signs were observed above the substance water solubility limits (0.0405 mg/l for p-DIPB and 0.072 mg/l for m-DIPB), so it can be concluded that there is no acute toxicity for test organisms up to water solubility limits.

Executive summary:

In a study conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test), Oryzias latipes were exposed to diisopropylbenzene concentrations for 96 h. The test was conducted using dispersant, and the estimated values were higher than water solubility, however, analytical monitoring was done. A 96 h LC50=0.707 mg/L (95% C.L.: 0.539 -0.935 mg/L; measured concentrations) was determined.

Description of key information

One study was carried out on the mixture of isomers (CERI, 2000) and two other studies were conducted on the isomers 1 ,3-DIPB and 1,4-DIPB respectively (Eastman, 1984, 1986).

The study performed on the mixture used dispersant, and the estimated toxicity values were found to be higher than the water solubility determined by CERI: 96 h LC50=0.707 mg/L (95% C.L.: 0.539 -0.935 mg/L; measured concentration).

The study conducted on the meta isomer used a flow-through, recirculating elutriation system designed to expose the organisms to an exposure concentration at or near the solubility of the test substance. Results of an unpublished 96-hour volatility study on m-DIPB indicated that the substance is extremely volatile in water with 100% of the material lost over 96-hours from a 1.9 mg/L solution. Therefore, the measured concentration of m-DIPB (0.93 mg/L) was the result of the low solubility and high volatility of the test substance, but reflected the most effective experimental flow-through design to maximize the exposure concentration. The toxicity test on p-DIPB was conducted in a similar manner. Therefore, these tests were conducted using the most effective experimental designs. All fish exhibited normal behavior. The conclusion was that the meta and para isomers are not toxic to fish at solubility limit.