1,6-dichloro-1,6-dideoxy-β-D-fructofuranosyl 4-chloro-4-deoxy-α-D-galactose

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1986-05-09 to 1987-01-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

version: adopted 7 June 1984

Deviations:

yes

Remarks:

extension of test duration to 96h

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: KL/5/31
- Purity test date: 99.2%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: in the dark in the deep freeze in the container in which it was received

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all test concentrations and the control
- Sampling method: At the start and finish of the test, samples were taken of each test solution, using excess remaining after filling the test vessels and one of the test replicates, respectively.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of the test substance in distilled water was prepared. Each test solution was prepared by the addition of aliquots of stock solution to sterile culture medium, with equalising additions of distilled water to a volume of 800 mL.
- Controls: culture medium only

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Green alga
- Strain: Selenastrum capricornutum Printz, ATCC 22662

ACCLIMATION
- Culturing media and conditions (same as test or not): same as test

Test type:

static

Water media type:

other: according to Miler et al 1978

Limit test:

no

Total exposure duration:

96 h

Test temperature:

23.7 - 24.2°C

pH:

test start: 7.2 - 7.3
test end: 9.5- 9.9

Nominal and measured concentrations:

nominal: control, 180, 320, 560, 1000 and 1800 mg/L
measured: <18, 170, 315, 540, 930, 1760 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: borosilicate glass conical flasks of 250mL nominal capacity with polyurethane foam bungs
- Material, size, headspace, fill volume: each flask contained 100 mL of test solution
- Initial cells density: 1.0 x 10^4 cells/mL
- Control end cells density: mean: 291.83 x 10^4 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: continuous illumination
- Light intensity and quality: 7550 Lux; 850 microwatts/cm²
- Other: shaking at 100 rpm

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: Coulter Counter Model ZB

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 1 800 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 1 800 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1 800 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate and biomass

Details on results:

The measured concentrations of the test substance at the start and finish ranged from 93% to 100% of the nominal values, and therefore the nominal concentrations were used to calculate the results.

Reported statistics and error estimates:

Dunnett's procedure was used to identify significant differences (P < 0.5) from the control.

Algal cell densities

nominal concentration [mg/L]	replicate	Algal cell density [x10^4 cells/mL]
		day 1	day 2	day 3	day 4
control	1	3.30	18.30	91.80	289.00
	2	3.73	20.50	103.00	310.00
	3	3.90	22.10	111.00	311.00
	4	3.43	19.50	95.10	286.00
	5	3.45	19.20	95.20	265.00
	6	3.56	20.50	104.00	290.00
	mean	3.56	20.02	100.02	291.83
180	1	3.61	21.70	108.00	304.00
	2	3.70	19.90	99.90	293.00
	3	3.78	21.50	109.00	295.00
	mean	3.70	21.03	105.63	297.33
320	1	3.60	19.50	98.50	299.00
	2	3.70	19.30	99.00	299.00
	3	3.79	20.00	102.00	290.00
	mean	3.70	19.60	99.83	296.00
560	1	3.82	19.30	104.00	294.00
	2	3.65	21.20	114.00	302.00
	3	3.82	19.70	104.00	299.00
	mean	3.76	20.07	107.33	298.33
1000	1	3.70	20.20	104.00	278.00
	2	3.70	21.30	110.00	293.00
	3	3.79	22.60	115.00	315.00
	mean	3.73	21.37	109.67	295.33
1800	1	3.57	19.20	96.20	272.00
	2	3.69	21.50	114.00	329.00
	3	3.38	19.30	104.00	301.00
	mean	3.55	20.00	104.73	300.67

inoculum (day 0) cell density = 1.05 x 10^4 cells/mL

Mean areas under the groth curve and growth rates and respective percentages of the control

nominal concentration [mg/L]	mean area under the growth curve	% control	mean growth rate (0-96 h)	% control
control	265.8	100	1.407	100
180	275.4	104	1.412	100
320	267.5	101	1.410	100
560	276.7	104	1.412	100
1000	278.8	105	1.410	100
1800	274.9	103	1.414	101

Validity criteria fulfilled:

not specified

Conclusions:

The toxicity of the test item on the green algae Selenastrum capricornutum was determined in a GLP study according to OECD 201 except the extension of test duration to 96 h. The 96-h EC50 was determined to be >1800 mg/L (nominal).

Description of key information

The toxicity of the test item on the green algae Pseudokirchneriella subcapitata (former: Selenastrum capricornutum) was determined in a GLP study according to OECD 201 except the extension of test duration to 96 h. The 96-h EC50 was determined to be >1800 mg/L (nominal).

Key value for chemical safety assessment

EC50 for freshwater algae:

1 800 mg/L

Additional information

The toxicity of test item on the green algae Pseudokirchneriella subcapitata (formar: Selenastrum capricornutum) was determined in a GLP study according to OECD 201 except the extension of duration time to 96 h. The algae was exposed to 0 (control), 180, 320, 560, 1000 and 1800 mg/L of the test substance in culture medium, equivalent to geometric mean measured concentrations of <18, 170, 315, 540, 930 and 1760 mg/L at the beginning. No impact on the biomass and the groth rate was observed after 96 h at 1800 mg/L. The 96 h EC50 value of >1800 mg/L (nominal) was concluded.