Magnesium perchlorate

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Data source

Reference

Reference Type:

publication

Title:

Single and joint effects of perchlorates to Daphnia magna: Additivity and interaction patternsI

Author:

Loureiro et al.

Year:

2012

Bibliographic source:

Fresenius Environmental Bulletin (FEB), Volume 21 - No. 4

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

OECD (2008) Guidelines for the Testing of chemicals. Daphnia magna reproduction test. In. OECD- Organization for Economic Cooperation and Development, Paris.

Deviations:

not specified

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium perchlorate

EC Number:

232-235-1

EC Name:

Ammonium perchlorate

Cas Number:

7790-98-9

Molecular formula:

ClHO4.H3N

IUPAC Name:

ammonium perchlorate

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: direct weighing to ASTM test water
- Controls: Yes, ASTM test water only.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): no

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna Straus
- Strain/clone: clone 6
- Age at study initiation (mean and range, SD): neonates < 24 h old
- Method of breeding: The cultures are maintained with 25 daphnids per 1 L glass beaker with 800ml of ASTM hard water, renewed three times a week, and daily fed with Pseudokirchneriella subcapitata (Korshikov) Hindak at a concentration of 3×105 cells/ml supplemented with an organic additive of seaweed extract of Ascophyllum nodosum. The cultures are kept in a 16:8 h light:dark cycle regime, at 20±1 °C.
- Source: Originally from Antwerp, Belgium, and cultures kept in controlled laboratory cultures for more than 3 years.
- Feeding during test: yes
- Food type: freshwater green algae Pseudokirchneriella subcapitata and an organic additive
- Amount: ad libitum
- Frequency: daily

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test conditions

Test temperature:

20 +/- 1 °C

Nominal and measured concentrations:

Nominal: 0, 40, 60, 80, 100, 120, 140, 160, 180 and 200 mg/L.
Measured: Ammonium concentrations obtained from the exposure solutions were converted in perchlorate concentrations and variation from real to nominal concentration was 5 - 15 %. Therefore, nominal concentrations were used for the evaluation of results.

Details on test conditions:

TEST SYSTEM
- Test vessel: not specified
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 50 mL test solution
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): every two days
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ASTM hard water according to ASTM (1998) "Standard practice for conducting toxicity tests with fishes, microinvertebrates and amphibians".
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Photoperiod: 16:8 h light:dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
The number of neonates and female mortality were recorded daily during the test period of 21 days. At the end of the test-period, the growth of the adults was also determined by measuring their body length (excluding the anal spine and antennas) under a stereomicroscope.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

80 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 2

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 3

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

120.22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Effect concentrations 4

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Effect concentrations 5

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

120 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Reported statistics and error estimates:

One-way analysis of variance (ANOVA) using the SigmaStat statistical package were used to test for statistical differences between different perchlorate concentrations. Whenever significant differences between treatments were found the post-hoc multiple comparison Dunnett's method was performed. Whenever data were not normally distributed, the heterogeneity of variance test failed and data transformation did not correct for normality, a Kruskal–Wallis ANOVA on Ranks was performed, followed by the Dunn's method when significant differences were found.
ECx values were calculated, when possible, with a sigmoidal curve using the software package SigmaPlot.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The long-term toxicity to Daphnia magna was tested according to OECD TG 211 on the structural analogue substance Ammonium perchlorate (CAS 7790-98-9) without remarkable deviations. Accordingly, the method is considered scientifically reasonable with minor deficiencies in documentaion and reliability of Klimisch 2 has been assigned.

The registration substance Magnesium perchlorate will rapidly dissolve in water and completely dissociate into the perchlorate anion and the corresponding cation. Accordingly, toxicity is determined only by the perchlorate moiety of the salt, as magnesium is known to be non-toxic. Based on that fact, it is considered entirely appropriate to use data of related perchlorate salts dissociating in water.

Based on the results obtained in the present study the following endpoints were determined:
NOEC (21 d) reproduction = 80 mg/L
LOEC (21 d) reproduction = 100 mg/L
EC10 (21 d) reproduction = 120.22 mg/L
NOEC (21 d) growth = 100 mg/L
LOEC (21 d) growth = 120 mg/L
Hence, Ammonium perchlorate showed to have low hazard for Daphnia magna and a comparable result is expected for the target substance Magnesium perchlorate when tested in this system.

Executive summary:

The study was conducted according to OECD 202 and ASTM (1998) on the structural analogue substance Ammonium perchlorate (CAS 7790-98-9). The registration substance Magnesium perchlorate will rapidly dissolve in water and completely dissociate into the perchlorate anion and the corresponding cation. Accordingly, toxicity is determined only by the perchlorate moiety of the salt, as magnesium is known to be non-toxic. Based on that fact, it is considered entirely appropriate to use data of related perchlorate salts dissociating in water.

The study was conducted with Daphnia magna exposed to nine nominal concentrations ranging from 40 to 200 mg/L and a negative control for 21 days under semi static test conditions. The number of neonates per female (reproduction) was recorded daily and the growth of the adults was also determined at the end of the test period. Statistical differences between different exposure concentrations and the control were tested by one-way analysis of variance (ANOVA) using the SigmaStat statistical package.

Ammonium concentrations obtained from the exposure solutions were converted in perchlorate concentrations and variation from real to nominal concentrations was between 5 - 15 %. Therefore, the evaluation of results was based on the nominal concentrations.

Based on the nominal concentrations the following endpoints were determined:

NOEC (21 d) reproduction = 80 mg/L

LOEC (21 d) reproduction = 100 mg/L

EC10 (21 d) reproduction = 120.22 mg/L

NOEC (21 d) growth = 100 mg/L

LOEC (21 d) growth = 120 mg/L