4-tert-butylbenzaldehyde

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was performed according to German national standard test guidelines. Scientifically acceptable. Non- GLP, a solvent was used

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: DIN 38412, part 9

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

4-tert-butylbenzaldehyde

EC Number:

213-367-9

EC Name:

4-tert-butylbenzaldehyde

Cas Number:

939-97-9

Molecular formula:

C11H14O

IUPAC Name:

4-tert-butylbenzaldehyde

Details on test material:

- Name of test material (as cited in study report): p-tert-butylbenzaldehyde
- Lot/batch No.: L 932 B
- Analytical purity: 99.4 % p-TBA

Sampling and analysis

Analytical monitoring:

no

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A concentration stock solution of the test item (nominal 1000 mg/L) was prepared by using Cremophor (200 mg/L) as a solvent. containi- Controls: 100 mg/L Cremophor
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Cremophor

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Nominal and measured concentrations:

Nominal test concentrations (mg/l):
0.05,
0.5,
5,
50,
500,
control,
solvent control,
Spacing factor = 2
control

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

5.81 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

13.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

31.86 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

Neither growth promotion induced by the test substance nor autofluorescence were observed.

Any other information on results incl. tables

During the 72 h exposure to 4-tert-butylbenzaldehyde, absorbance values  were as follows (average of the
4 replicates):

Nominal test          Absorbance after x hours
concentration       0         24        48        72 
Control             0.03     0.10      0.30      0.46
Solvent control     0.03     0.11      0.31      0.53
  0.05 mg/l         0.03     0.09      0.28      0.39
  0.5  mg/l         0.03     0.10      0.28      0.40
  5.0  mg/l         0.03     0.10      0.28      0.44
 50.0  mg/l         0.03     0.03      0.03      0.03
500.0  mg/L         0.03     0.00      0.00      0.00
-----------------------------------------------------------
Growth rates and percent inhibition of biomass after 72 h and were:

Nominal test        Growth     %      Biomass     %
concentration       rate   inhibition          inhibition
Control             0.91      -4.43     0.55      11.42
Solvent control     0.95       -        0.60        -
  0.05 mg/l          0.85     10.39     0.49        2.51
  0.50 mg/l          0.86      9.94     0.50        3.77
  5.00 mg/l          0.89      6.57     0.52        4.66
 50.00 mg/l         -0.06    106.37     0.78       24.42
500.00 mg/l          1.17    -22.51     0.38       62.70
99.05 mg/L         -1.00    207.55    -0.11      110.33

All results refer to the solvent control values.

----------------------------------------------------------
The 72 hour EC-values of both biomass (B) and growth rate (µ) were  calculated using probit analysis:

EµC10  =   5.81 mg/l 
EµC50  =  13.60 mg/l 
EµC90  =  31.86 mg/l 


The EC-values for the endpoint biomass inhibition were:
EBC10  =   4.28 mg/l 
EBC50  =  11.31 mg/l 
EBC90  =  29.98 mg/l