Methoxyammonium chloride

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, GLP, Monitoring.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Bis(hydroxylammonium) sulphate

EC Number:

233-118-8

EC Name:

Bis(hydroxylammonium) sulphate

Cas Number:

10039-54-0

Molecular formula:

H3NO.1/2H2O4S

IUPAC Name:

bis(hydroxyammonium) sulfate

Details on test material:

- Analytical purity: 99.13 %

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: The concentration control analyses were performed with test solutions of the following nominal concentrations of the test substance: 0, 1.0, 0.5, 0.25, 0.125, 0.0625, 0.0313, 0.0156 mg/l. Samples for analysis were taken in the 1st, the 2nd and the 3rd week of the test. For each concentration the freshly prepared test solution (unstocked) and the corresponding 24h old test solution (stocked with daphnids) were analyzed.
- Sampling method/ Storage: To 50 mL test solution 3 drops 10% H2SO4 were added to stabilize the concentration. Retain samples were taken and stored in the refrigerator.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test concentrations were prepared by serial dilution of a stock solution. The stock solutions for the test intervals were prepared by dilution of 1 mg test substance in 1 L test water followed by stirring with a magnetic stirrer for about 1 hour. The stock solution appeared colorless clear.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: The clone of Daphnia magna STRAUS used was supplied by Institut National de Recherche Chimique Appliquée, France, in 1978. The daphnids are cultured under standard conditions in the laboratory of ecotoxicology, BASF AG, "Ludwigshafen".
- Age of parental stock: 2-4 weeks
- Age of the animals at the start of the test: 2 -24 h
- Culture conditions: The daphnid tests are performed under the same environmental conditions as the culture itself.
- Changing of the breeding water: Monday, Friday
- Feeding during test: Yes, Desmodesmus subspicatus, cultured in a synthetic medium, daily

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test conditions

Hardness:

2.20 - 3.20 mmol/L

Test temperature:

20.3 - 21.2 °C

pH:

7.6 - 8.3

Dissolved oxygen:

5.3 - 9.4 mg/L

Nominal and measured concentrations:

0, 1, 0.5, 0.25, 0.125, 0.0625, 0.0313, 0.0156 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: closed test system with numbered glass vessels with glass plugs (nominal volume approx. 50 mL)
- Fill volume: approx. 50 mL (Because of the volatility of the test substance the test vessels were closed with a glass plug and filled without headspace).
- Renewal of test solution: daily
- No. of organisms per vessel: 1 parent animal
- No. of vessels per concentration (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: synthetic medium M4
- This synthetic medium has the following properties:
Alkalinity up to pH 4.3: 0.80 - 1.00 mmol/L
Molar ratio Ca:Mg: about 4 : 1
pH value: 7.5-8.5
Conductivity: 550 - 650 uS/cm
- After preparation the M4 medium was aerated for approximately 24 h until saturation with oxygen is reached.

OTHER TEST CONDITIONS
- Photoperiod: Artificial Iight, OSRAM L58 W31 warm white; day/night-rhythm = 16 / 8 hours
- Light intensity: about 1 - 8 µE/(m2.s) at a wave length of 400 - 700 nm
Because of the volatility of the test substance the test vessels were filled without headspace and closed with glass plugs.

EFFECT PARAMETERS MEASURED
- Reproduction and mortality, daily observation intervals

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.31 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

other: length

Effect concentrations 2

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 0.616 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

reproduction

Any other information on results incl. tables

a) Analytically measured concentrations of the test substance in the test solution:

Nominal	1. sampling		2. sampling		3. sampling		Mean	Mean
Conc.	day 0	day 1	day 8	day 9	day 20	day 21	value*	value*
[mg/L]	[mg/L]	[mg/L]	[mg/L]	[mg/L]	[mg/L]	[mg/L]	[mg/L]	[%]
0	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01	< 0.01
0.0156	0.017	< 0.01	0.017	< 0.01	0.017	< 0.01	0.0085	54.5
0.0313	0.035	< 0.01	0.033	< 0.01	0.035	< 0.01	0.017	54.8
0.0625	0.085	< 0.01	0.063	< 0.01	< 0.01	< 0.01	0.025	39.5
0.125	0.169	< 0.01	0.128	0.017	0.140	< 0.01	0.076	60.5
0.250	0.33	< 0.01	0.250	0.019	0.263	< 0.01	0.144	57.5
0.500	0.718	< 0.01	0.552	0.064	0.516	< 0.01	0.308	61.7
1.000	1.265	0.013	1.055	0.236	1.081	0.048	0.616	61.6

*The mean value was calculated as arithmetic mean of the concentration at  start of the intervals and the limit of quantification if the  concentration at the end of the intervals was below the limit of  quantification.

The analytically determined concentrations of the test substance in the  test water were in a range of 80 . 120 % of the nominal concentration for  the freshly prepared solution with the following exceptions:
- 127-144 % of the nominal value were detected in the concentrations  >=0.0625 mg/L
on day 0
- the concentration was below the detection limit on day 20 in the test  concentration 0.0625 mg/L.

At the end of the test intervals after 24 hours, the substance decomposed  almost completely. Only in the highest test concentration, it was  possible to detect low amounts of the test substance after 24 hours.

In a preliminary stability test at a very low concentration of 10 µg/L  the decomposition of the test substance was very fast. In higher  concentrations the decompositions seems to be slower. The highest  selected test concentration in this study was 1 mg/L based on the results  of an acute study.


b) Biological results:

Nominal concentrations:

Reproduction/ Weight/ Length
NOEC [mg/L] >= 1/ >= 1/ 0.5
LOEC [mg/L] > 1/ > 1/ 1


Measured concentrations:

Reproduction/ Weight/ Length
NOEC [mg/L] >=0.616/ >= 0.616/ 0.308
LOEC [mg/L] > 0.616/ >  0.616/ 0.616



Summary of the LC0 (mortality of the parent animals) after 21 days

LC0 >= 1 mg/L (nominal)
LC0 >= 0.616 mg/L (measured)

Since the toxicity observed in this test may be caused by the instable  test substance and/or by its degradation products and since the half life  period is very short, the effect concentration, which is based on the  nominal concentrations, should be preferably used for the evaluation of  the test substance.

c) Water parameter:

Minimum and maximum values of the chemical and physical characteristics  of the test solutions during the test period.

Parameter                               Minimum                 Maximum
--------------------------------------------------------------------------------------------
pH value                                     7.6                          8.3
Oxygen content [mg/L]             5.3                          9.4
Temperature [°C]*                    20.3                        21.2
--------------------------------------------------------------------------------------------
* measured in a separate vessel close to the test vessels