Nitrosylsulphuric acid

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010-02-02 to 2010-02-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study was performed and reported in compliance with the OECD Guideline 202, EC and German principles of GLP.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Principles of method if other than guideline:

Not applicable.

GLP compliance:

yes (incl. QA statement)

Remarks:

GLP certificate of the test facility is available

Test material

Test material information

Constituent 1

Reference substance name:

Nitrosylsulphuric acid

EC Number:

231-964-2

EC Name:

Nitrosylsulphuric acid

Cas Number:

7782-78-7

Molecular formula:

HNO5S

IUPAC Name:

hydroxy(nitrosooxy)sulfane dioxide

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): LZ5593
- Physical state: Viscous liquid
- Expiration date of the lot/batch: 2011-11-20
- Storage condition of test material: Room temperature, protected from moisture and light.
- Purity test date: 2009-11-20

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No details available.

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All concentration levels, the pH control and the control were analytically verified in the fresh media (0 h) and old media (48 h) via UV spectrophotometry using the sulphate pipette test (LCK 153, HACH LANGE).
- Sampling method: For the old media, additional replicates of all concentration levels, the pH-control end control without test organisms were
prepared and incubated under test conditions.
- Sample storage conditions before analysis: Immediate analysis

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of 100 mg/L was freshly prepred with dilution water and agitated.
- Eluate: Dilution water
- Differential loading: 6.25 - 12.5 - 25.0 - 50.0 - 100 mg/L
- Controls: Dilution water without test item tested under the same conditions as the test groups.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (STRAUS)
- Strain: Clone 5
- Source: Institut für Wasser-, Boden- Lufthygiene (WaBoLu), further own breeding
- Age at study initiation (mean and range, SD): 2 to 24 h
- Method of breeding: In 2-3 L glass vessels with appr. 1.8 L culture medium, at 20 +/- 2 °C, in an incubator, 16 h illumination, illumination strength max. 20 µExm-2 x s-1
- Feeding during test: No feeding

ACCLIMATION
- Acclimation period: 2 h
- Acclimation conditions (same as test or not): Same as test
- Type and amount of food: No feeding
- Health during acclimation (any mortality observed): Healthy, no mortality observed

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

No

Test conditions

Hardness:

Dilution water at test start: 274 (mg CaCO3/L)

Test temperature:

19 - 20 °C

pH:

Water Quality Parameters at the Beginning of the Test (0 h, Fresh Media)
(measured in one additional replicate per concentration level, pH-control and control)
Nominal concentration
of the test itemLZ5593
[mg/L] pH-Value
100 (pH control)* 7.00
100 3.06
50.0 3.87
25.0 6.38
12.5 6.78
6.25 7.08
Control 7.75

Water Quality Parameters at the End of the Test (48 h, Old Media)
(measured in all replicates)
Nominal concentration
of the test item LZ5593
[mg/L] pH-Values Replicates
1 2 3 4
100 (pH control)* 7.22 7.20 7.31 7.32
100 3.97 3.07 3.07 3.06
50.0 3.11 3.95 4.01 3.94
25.0 7.09 7.08 7.10 7.10
12.5 7.31 7.35 7.34 7.30
6.25 7.40 7.38 7.41 7.36
Control 7.67 7.33 7.41 7.38

Dissolved oxygen:

Water Quality Parameters at the Beginning of the Test (0 h, Fresh Media)
(measured in one additional replicate per concentration level, pH-control and control)
Nominal concentration
of the test item
LZ5593
[mg/L] O2-Concentration [mg/L]
100 (pH control)* 7.40
100 7.72
50.0 7.70
25.0 7.71
12.5 7.75
6.25 7.60
Control 8.22

Water Quality Parameters at the End of the Test (48 h, Old Media)
(measured in all replicates)
Nominal concentration
of the test item
LZ5593
[mg/L] O2 -Conc. [mg/L]
Replicates
1 2 3 4
100 (pH control)* 7.50 7.62 7.45 7.44
100 7.93 7.81 7.79 7.68
50.0 7.82 7.75 7.83 7.76
25.0 7.71 7.62 7.76 7.57
12.5 7.41 7.77 7.80 7.67
6.25 7.90 7.74 7.89 7.81
Control 7.64 7.91 7.89 7.88

Salinity:

Freshwater

Nominal and measured concentrations:

Please refer to "Any other information on materials and methods incl. tables"

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers, 50 mL
- Type (delete if not applicable): closed with parafilm
- Material, size, headspace, fill volume: Glass beakers (4 cm ID x 7 cm H), 50 mL
- Aeration: No
- Renewal rate of test solution (frequency/flow rate): One application at test start, static test
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): None

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Acc. to Directive 92/69/EEC Method C.2, Annex 1
- Conductivity: Dilution water at test start: 640 µS/cm
- Culture medium different from test medium: Elendt M4 acc. to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L
- Intervals of water quality measurement: At test start and test end

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16:8 light:dark cycle
- Light intensity: Diffuse light, illumination strength max. 20 µE x m-2 x s-1

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
The percentage immobility was determined in all test and control groups after 24 and 48 h. An animal was considered to be immobile, if it was not
able to swim within 15 sec after gentle agitation of the test vessel.

TEST CONCENTRATIONS
- Immobilization Rates of the Preliminary Range Finding Test [%]
(n = 20, divided into 2 replicates 10 daphnids each)
Nominal
Test Item
Concentration
[mg/L] IMMOBILIZATION [%]
24 h 48 h
Replicates Replicates
1 2 MV 1 2 MV
100 (pH control)* 0 0 0 40 0 20
100 100 100 100 100 100 100
Control 0 0 0 0 0 0

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

35.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 25.0-50.0 mg/L

Details on results:

- Behavioural abnormalities: No
- Observations on body length and weight:No
- Other biological observations:No
- Mortality of control: 0 %
- Other adverse effects control: None observed

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- EC50/LC50: 1.60 (CI 1.44 - 1.84) mg/L

Reported statistics and error estimates:

EC50-values were calculated as the geometric mean of the lowest concentration causing 100 % immobilization (50.0 mg/L) and the highest concentration causing 0 % immobilization (25.0 mg/L), because only 0 and 100 % immobilization was observed. These concentration levels were also used as
confidence limits.
Calculation of EC10-values was not applicable due to the data obtained.

Any other information on results incl. tables

Percentage of Daphnids Incapable of Swimming after 24 and 48 h of Exposure

              (n = 20, divided into 4 replicates with 5 daphnids each)

Nominal Concentration of the Test Item LZ5593	IMMOBILIZATION [%]
	24 h					48 h
	Replicates					Replicates
[mg/L]	1.	2.	3.	4.	MV	1.	2.	3.	4.	MV
100 (pH control)*	0	0	0	0	0	0	0	0	0	0
100	100	100	100	100	100	100	100	100	100	100
50.0	100	100	100	100	100	100	100	100	100	100
25.0	0	0	0	0	0	0	0	0	0	0
12.5	0	0	0	0	0	0	0	0	0	0
6.25	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Based on the nominal concentrations of the test item LZ5593 the 48-hour EC50 for Daphnia magna was estimated to be 35.4 mg/L (95 % confidence limits: 25.0 - 50.0 mg/L).
The NOEC after 48 h was assessed at 25.0 mg test item/L as the highest tested concentration with no biologically significant effect (Immobilization rates of > 10 % are seen to be not significant according to the guideline). The LOEC was determined to be 50.0 mg test item/L.

Executive summary:

The acute immobilization of the test item LZ5593 to Daphnia magna (STRAUS) was determined according to OECD 202 (2004) from 2010-02-02 to 2010-02-04.
The study was conducted with 5 nominal test item concentrations ranging from 6.25 to 100 mg/L set up in a geometric series with a dilution factor of 2under static conditions over a period of 48 h. Additionally a pH control was tested. 20 test organisms were exposed to each test concentration and control.

The sulphate content as a component of the test item LZ5593 was analysed via UV-spectrophotometry with a pipette test at all test item concentrations, the pH control and the control after 0 h and 48 h. Details of the analytical method are given in part 10. The recovery rates in the fresh (0 h) and old media (48 h) of the biologically relevant test concentrations of 25.0 to 100 mg/L were in the range of 93 % to 117 % of the nominal values.
Therefore, all effect values given are based on the nominal concentrations of the test item LZ5593.
Water quality parameters (pH-value and dissolved oxygen concentration), measured at 0 h and 48 h, were determined to be within the acceptable limits. The validity criteria of the test guideline were fulfilled.

Table 1:    EC₁₀-, EC₅₀- (with Confidence Interval), EC₁₀₀- Values, NOEC and LOEC

(based on the nominal concentrations of the test item LZ5593)

	Test Duration [h]	Nominal Concentration of the Test Item LZ5593 [mg/L]	Confidence Interval p = 95% [mg/L]
EC10	24	Not applicable	---
	48	Not applicable	---
EC50	24	35.4	25.0 – 50.0
	48	35.4	25.0 – 50.0
EC100	24	50.0	---
	48	50.0	---
NOEC	48	25.0	---
LOEC	48	50.0	---