Dichloride titanium oxide

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: comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Principles of method if other than guideline:

Acute toxicity study on Pseudokirchneriella subcapitata. Testing parameter: growth rate

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Titanium dioxide

EC Number:

236-675-5

EC Name:

Titanium dioxide

Cas Number:

13463-67-7

IUPAC Name:

dioxotitanium

Constituent 2

Reference substance name:

Rutile (TiO2)

EC Number:

215-282-2

EC Name:

Rutile (TiO2)

Cas Number:

1317-80-2

IUPAC Name:

dioxotitanium

Details on test material:

- Name of test material (as cited in study report): Titanium dioxide, R101 Pigment Grade (H-27415)
- Analytical purity: 98.4 % Titanium dioxide

- Name of test material (as cited in study report): Titanium dioxide, Ultrafine (H-27416)
- Analytical purity: 89.3 % Titanium dioxide

Test solutions

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solutin was prepared (120 mg/l). The test substance was added tofilter-sterilized AAP nutrient medium, the solution was sonicated for approximately 30 minutes and stirred for approximately 30 minutes. The test solutions were prepared separately.

Test organisms

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Source (laboratory, culture collection): cultured and maintained at Haskell Laboratory. The original culture source was the Department of Botany - Culture Collection of Algae - The University of Texas at Austin, USA

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

23.7 - 23.8 °C

pH:

7.79 - 8.18

Nominal and measured concentrations:

Nominal test concentrations:
blank control, 0.01, 0.1, 1, 10, and 100

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flasks (250 ml)
- Fill volume: 50 ml
- Initial cells density: 10000 cells/ml
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2



TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: AAP medium



OTHER TEST CONDITIONS
- Photoperiod: 24 h
- Light intensity and quality: 8200 to 9500 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: hemacytometer and a compound microscope

Results and discussion

Effect concentrations

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

61 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

H-27415

Basis for effect:

growth rate

Remarks on result:

other: 52 to 72 (95% fiducial limits)