Phosphonic acid, P-phenyl-, zinc salt (1:1)

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

Study period:

09 to 12 February 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study undertaken to GLP following internationally accepted guidelines.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: Algae growth inhibition test; stated in Method of Testing New Chemical Substances (November 21, 2003, Yakushoku hatsu No. 1121002, Nov. 13, 2003, Seikyoku No.2, Kanpoki hatsu No. 031121002, partially modified on November 20, 2006)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

zinc(2+) phenylphosphonate

EC Number:

696-577-7

Cas Number:

34335-10-9

Molecular formula:

C6 H7 O3 P. Zn C6H5-P(=O)O2,2+Zn2-

IUPAC Name:

zinc(2+) phenylphosphonate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Phenylphosphonic acid zinc salt
- Substance type: inorganic
- Physical state: white powder
- Analytical purity: > 99%
- Purity test date:
- Lot/batch No.: 6381
- Stability under test conditions: stable
- Storage condition of test material: Stored in desiccators in a dark place at room temperature.

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 10,3.2, 1.0,0.32, and 0.10 %
- Sampling method:
- Sample storage conditions before analysis:

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test sample and the medium were mixed to make a 100 mg/L (nominal value) solution, and was stirred with a magnetic stirrer for about 48 hours. The solution was then filtrated under suction with a membrane filter (manufactured by Millipore, GV, pore size 0.22 Ilm). The filtrate was used as stock solution. Required amount of the stock solution was mixed with the medium'3 in a preparation container, stirred to obtain test solution, and was divided in each test vessels.
- Eluate: The medium stated in OECD Guidelines for Testing Chemicals (Guideline 201, 23 March 2006) was used for both the preliminary culture and the definitive test.
- Differential loading:
- Controls:Yes

Test organisms

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Algae
- Strain: ATCC 22662
- Source (laboratory, culture collection): Test organisms was obtained from American Type Culture Collection (12301 Parklawn Drive, Rockville, Maryland 20852-1776 U.S.A.) on June 30, 1995

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Hardness:

no data

Test temperature:

22.8 to 23.0°C

pH:

7.8 - 7.9

Dissolved oxygen:

no data

Salinity:

no data

Nominal and measured concentrations:

measured; 0.014, 0.043, 0.11, 0.33 and 0.96 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 500 ml conical flask
- Type: closed
- Fill volume: 300 ml
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): no
- Initial cells density: 1xE4 cells/ml
- Control end cells density: ~60xE4 cells/ml
- No. of organisms per vessel:
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: no
- Detailed composition if non-standard medium was used: The medium stated in OECD Guidelines for Testing Chemicals (Guideline 201, 23 March 2006) was used for both the preliminary culture and the definitive test.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The medium stated in OECD Guidelines for Testing Chemicals (Guideline 201, 23 March 2006) was used for both the preliminary culture and the definitive test.
- Culture medium different from test medium:
- Intervals of water quality measurement: no

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: no
- Photoperiod: no data
- Light intensity and quality: 92 to 96 µE/m2/s

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: electronic particle counter;
- Chlorophyll measurement: no
- Other:

TEST CONCENTRATIONS
- Spacing factor for test concentrations: root 10
- Justification for using less concentrations than requested by guideline:
- Range finding study; no

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

3 d

Dose descriptor:

NOEC

Effect conc.:

0.11 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.37 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limit: 0.36 - 0.38 mg/L

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no data

Results with reference substance (positive control):

No positive control used.

Any other information on results incl. tables

pH ofthe test solution

easured concentration * (mg/L)	pH
	At the start	At the end
Control group	7.9	7.8
0.014	7.9	7.8
0.043	7.9	7.8
0.11	7.9	7.8
0.33	7.9	7.8
0.96	7.9	7.8

* : Geometric average of measured concentrations (hereinafter referred to as measured concentration)

Temperature and light intensity inside the incubator

Exposure period	At the start	Day 1	Day 2	At the end
Temperature inside the incubator (˚C)	23.0	23.0	22.8	22.9
Light intensity (µE/m^2/s)	96	92	95	95

Growth rate and growth inhibition rate

Measured concentration (mg/L)	Group	Growth rate (0 – 3 days)	Inhibition rate (%)
Control group	A	1.3	-
	B	1.5	-
	C	1.3	-
	D	1.3	-
	E	1.4	-
	F	1.3	-
	Average S.D	1.4 0.076	- -
0.014	A	1.4	-0.78
	B	1.3	3.6
	C	1.3	2.0
	Average S.D	1.3 0.030	1.6 2.2
0.043	A	1.3	3.8
	B	1.3	2.4
	C	1.3	5.3
	Average S.D	1.3 0.019	3.8 1.4
0.11	A	1.3	2.3
	B	1.3	4.8
	C	1.4	-0.28
	Average S.D	1.3 0.034	2.3 2.5
0.33	A	0.76	44
	B	0.72	47
	C	0.75	45
	Average S.D	0.74 0.024	45 1.8
0.96	A	0.18	87
	B	0.17	87
	C	0.16	88
	Average S.D	0.17 0.0097	87 0.71

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of this study it was found that the test substance inhibits the growth of algae.