Reaction mass of sulphuric acid, hydrogen peroxide and peroxomonosulphuric acid

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2008-12-08 to 2009-02-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The reaction mass of sulphuric acid, hydrogen peroxide and peroxomonosulphuric acid is predominantly sulphuric acid (>80%). Although all constituents of the reaction mass contribute towards and are essential for the desired technical effects of the range, it is considered acceptable to read-across to data on sulphuric acid. This because significant toxicological effects are likely to be masked in the multi-constituent substance by its corrosive nature and so it considered appropriate to read across to the mean constituent, sulphuric acid, when considering aquatic toxicity.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See read-across data matrix under 'Attached background material' below.

3. ANALOGUE APPROACH JUSTIFICATION
See read-across data matrix under 'Attached background material' below.

4. DATA MATRIX
See read-across data matrix under 'Attached background material' below.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection 2005-09-14 to 2005-09-16 and 2005-10-26 to 2005-10-28; Date of signature 2006-01-11

Analytical monitoring:

yes

Details on sampling:

- Zero and 48 h (test system)
- Zero and 48 h (control)

Vehicle:

no

Details on test solutions:

- Reconstituted water (M4 medium) was used for maintenance of the test animals and preparation of stock/test solutions.
- To produce the only test concentration, 105.5 mg of the test material was added to 1L of dilution water.
- The pH was determined to be 4.0 and was adjusted to pH 8.0 with 1 M sodium hydroxide solution.
- Stock solution (19 mL) was taken and diluted with 1 mL dilution water containing 10 daphnids resulting in a final concentration of 100 mg/L.
- Two replicates were prepared for the test system and the control.

Test organisms (species):

Daphnia magna

Details on test organisms:

- A population of parthenogenetic females of synchronised age structure was maintained for more than 15 y in the test facility at 20 ± 1 °C in a 16:8 light-dark photoperiod (illumination < 1000 lux).
- The culture water (M4 medium) was partly renewed once a week.
- Daphnia were exclusively fed with unicellular green algae (Desmodesmus subspicatus) ad libitum.
- Mortalities of parent Daphnia were recorded daily during the culture period in a semi-quantitative manner.
- Neonates were separated from parent Daphnia by filtration prior to the acute test.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

Not applicable

Hardness:

275 mg/L CaCO3

Test temperature:

19.6 to 19.8 °C

pH:

- Control pH 8.0 (zero h)
- Control pH 7.8 (48 h)
- Test system pH 8.0 (zero h)
- Test system pH 7.9 (48 h)

Dissolved oxygen:

> 3 mg/L throughout the exposure period

Salinity:

Not applicable

Nominal and measured concentrations:

100 mg/L (nominal)

Details on test conditions:

- Test vessels: 50 mL glass beakers holding 10 neonates in 20 mL of test medium covered with watch-glasses.
- No feeding took place during exposure.
- Photoperiod: 16 h light and 8 h dark.
- Aeration: None.
- Medium renewal: None.
- Adverse effects were assessed via test material-induced alteration of the normal mobility behaviour and the loss of locomotory actions of the neonates (observed at 24 h and 48 h).

Reference substance (positive control):

not specified

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: pH 7.9 to pH 8.0

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: pH 7.9 to pH 8.0

Details on results:

CONTROL
- Values at zero h were declared as outliers.
- Values after 48 h equal the values of the pre-test (51 mg/L) and the theoretical amount of sulphate (48 mg/L) in the dilution water.
- Therefore the values after zero h were replaced with the values after 48 h for further calculations.

TEST SYSTEM
- Results were expressed in terms of nominal concentrations.
- Recovery rates were corrected for sulphate content of the controls.
- Recovery rate corresponds to 109.5 % of nominal at zero h.
- Recovery rate corresponds to 102.9 % of nominal at 48 h.
- Recovery rates relate to the concentration of 48.0 % H2SO4 in the test material.

Reported statistics and error estimates:

Not reported

JUSTIFICATION FOR USE OF READ-ACROSS DATA

See comparison of overall physico-chemical and toxicity profiles for target and source chemicals in the data matrix (attached).

Validity criteria fulfilled:

yes

Conclusions:

No toxic effects on Daphnia were observed at a limit test concentration of 100 mg/L and the EC50 (48 h) value was reported as > 100 mg/L.

Description of key information

EC50 (48 h) > 100 mg/L (OECD 202)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

Sulphuric acid, peroxomonosulphuric acid and hydrogen peroxide are each expected to contribute to the physico-chemical properties of the multi-constituent substance. However, significant toxicological effects are likely to be masked in the multi-constituent substance by its corrosive nature. It is therefore considered appropriate to read-across to the main constituent, sulphuric acid, when considering aquatic toxicity.