Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
short-term toxicity to aquatic invertebrates
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:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
yes
Remarks:
One exposure concentration at the solubility of the TS
GLP compliance:
yes
Analytical monitoring:
yes
Details on sampling:
Aliquots of exposure solution were submitted for concentration determinations at 0, 24, and 48 hours. Temperature, dissolved oxygen, and pH were also determined at these same time periods.
Vehicle:
no
Details on test solutions:
Separate tests indicated that the test substance exhibited low solubility 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 (0.91-0.96 mg/L at 0 and 48 hours). No protocol deviations were noted. Study was conducted in duplicate and results were averaged.
Test organisms (species):
Daphnia magna
Test type:
other: Static w/ recirculating elutriation system
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h
Nominal and measured concentrations:
Nominal concentration: 50 mg/L
Measured conc.: 0.93 mg/L (Average of the two replicate means)
Reference substance (positive control):
no
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 0.93 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: Average of the two replicate means
Details on results:
The exposed Daphnia exhibited behavior comparable to controls.
Reported statistics and error estimates:
NA, There were no effects 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 Daphnia magna for 48H in a methodology equivalent to OECD 202 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. Separate tests indicated that the test substance exhibited low solubility and high volatility in water. 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 exposed Daphnia exhibited behavior comparable to controls and it can be stated that m-DIPB is not toxic to Daphnia at solubility limit.

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1984
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:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation 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. No significant protocol deviations were noted that would affect study results.
Test organisms (species):
Daphnia magna
Test type:
other: Static w/ recirculating elutriation system
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h
Nominal and measured concentrations:
Nominal concentration: 100 mg/L (concentration assumed to reach equilibrium at the limit of solubility)
Measured conc.: Not conducted
Reference substance (positive control):
no
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 3 mg/L
Nominal / measured:
estimated
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 3 mg/L was found to be the limit of solubility of the TS
Details on results:
The exposed Daphnia exhibited behavior comparable to controls.
Reported statistics and error estimates:
NA, There were no effects noted.
Conclusions:
No effects were seen at the solubility limit of the test substance.
Executive summary:

p-DIPB was tested for acute toxicity towards Daphnia magna for 48H in a methodology equivalent to OECD 201 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. No effects were seen at the solubility limit of the test substance and it can be stated that p-DIPB is not toxic to daphnia at solubility limit.

Endpoint:
short-term toxicity to aquatic invertebrates
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:
read-across source
Reason / purpose:
read-across source
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 0.93 mg/L
Nominal / measured:
meas. (not specified)
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: Average of the two replicate means
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 EC50 values were derived for the DIPB mixture of isomers from experimental results on the souce substances m-DIPB and p-DIPB. The 48H-LC50 for the target substance was determined to be above 0.93 mg/L, which is considered to be the maximum reachable concentration considering the low solubility and the high volatility of the substances.
Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
disregarded due to major methodological deficiencies
Reliability:
3 (not reliable)
Rationale for reliability incl. deficiencies:
other: unsuitable test system
GLP compliance:
no
Analytical monitoring:
no
Vehicle:
no
Test organisms (species):
other: Balanus amphitrite niveus (nauplii)
Test type:
static
Water media type:
saltwater
Total exposure duration:
1 h
Conclusions:
Nauplii of Balanus amphitrite niveus were exposed to diisopropylbenzene for 1 h and the percentage saturation at which half the larvae (1 h D50) were sent to the bottom of the test device was determined. The 1 h D50 is reported to be 6% (ca. 9 mg/L).
Endpoint:
short-term toxicity to aquatic invertebrates
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 reliable
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes
Analytical monitoring:
yes
Vehicle:
yes
Test organisms (species):
Daphnia magna
Test type:
semi-static
Water media type:
freshwater
Total exposure duration:
48 h
Duration:
48 h
Dose descriptor:
EC0
Effect conc.:
0.246 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.392 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 0.624-0.843 mg/L
Effect Data:
EC50 (24hr) = 0.725 mg/L (mc) (95% C.I.=0.624-0.843 mg/L)
EC0 (24hr) = 0.246 mg/L (mc)
EC50 (48hr) = 0.392 mg/L (mc) (95% C.I.=0.246-0.754 mg/L)
EC0 (48hr) = 0.246 mg/L (mc)
mc: based on measured concentrations

Mortality or Immobility: No test organisms were immobilized at control, solvent control, 0.200 and 0.360 mg/L. One
individual was immobilized at 0.630 mg/L after 24 hours. All individuals were immobilized at 1.10mg/L after 48th hour and 2.00 mg/L on and after 24th hour.

---------------------------------------------------------
Nominal Cumulative Number of Immobilized Daphnids
(Percent Mortality or Immobility)
Conc. Mean* -----------------------------------
mg/L mg/L 24Hour 48Hour
---------------------------------------------------------
Control ---- 0 ( 0 ) 0 ( 0 )
Solvent
Control ---- 0 ( 0 ) 0 ( 0)
0.200 0.134 0 ( 0 ) 0 ( 0 )
0.360 0.246 0 ( 0 ) 0 ( 0 )
0.630 0.419 1 ( 5 ) 12 ( 60 )
1.10 0.754 10 ( 50 ) 20 ( 100 )
2.00 1.36 20 ( 100 ) 20 ( 100 )
---------------------------------------------------------
*: Mean measured concentration (Geometric Mean)


- Calculation of toxicity values: To calculate toxicity, the mean measured concentrations was used.

Water chemistry (pH and DO) and temperature in test: Water chemistry and temperature were measured for control and each concentration at the start and 24th hour.
pH: 8.2 - 8.6
DO: 8.4 - 8.8 mg/L
Water Temperature: 19.9 - 20.0 degrees C

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 were not less than +/- 20%.

---------------------------------------------------------
Nominal Measured Conc., mg/L Percent of Nominal
Conc. --------------------- ------------------
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 0.159 0.113 0.134 80 57
0.360 0.279 0.217 0.246 78 60
0.630 0.469 0.374 0.419 74 59
1.10 0.863 0.658 0.754 78 60
2.00 1.52 1.21 1.36 76 61
---------------------------------------------------------
Fresh: freshly prepared test solution
Old: test solution after 24 hours exposure
*: Mean measured concentration during 24 hours
(Geometric mean)
Validity criteria fulfilled:
no
Remarks:
All toxic signs were above solubulity limit
Conclusions:
In a study conducted according to OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test), Part I, Daphnia magna were exposed to diisopropylbenzene concentrations for 48 h. The test was conducted using solvent (mixture of a dispersant of HCO40 and DMF) and the estimated values were higher than water solubility, however, analytical monitoring was done. A 48h EC50=0.392 mg/L (95% C.L.: 0.624 -0.843 mg/L; measured concentration) was determined.
Executive summary:

In a study conducted according to OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test), Part I, Daphnia magna were exposed to diisopropylbenzene concentrations for 48 h. The test was conducted using solvent (mixture of a dispersant of HCO40 and DMF) and the estimated values were higher than water solubility, however, analytical monitoring was done. A 48h EC50=0.392 mg/L (95% C.L.: 0.624 -0.843 mg/L; measured concentration) 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: 48h EC50 = 0.392 mg/L (95% C.L.: 0.624 -0.843 mg/L; measured concentration).

The meta isomer was tested for acute toxicity towards Daphnia magna for 48H in a methodology equivalent to OECD 202 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. Separate tests indicated that the test substance exhibited low solubility and high volatility in water. 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. The exposed daphnia exhibited behavior comparable to controls The conclusion was that the meta and para isomers are not toxic to daphnia at solubility limit.

Key value for chemical safety assessment

Additional information