Diammonium peroxodisulphate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-05-11 to 2018-07-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

02 October 2012

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.20 (Daphnia magna Reproduction Test)

Version / remarks:

14 February 2017

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1300 (Daphnid Chronic Toxicity Test)

Version / remarks:

April 1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 3.0, 5.8, 10.9, 20.8, 39.5 and 75.0 mg/L.
- Sampling method:
The analysis of test concentrations was performed from each testing concentration and the control at the start and at the end of the first two water renewal period and then once per week (analyses were performed on a sample from the same solution - when freshly prepared and at renewal).
Analytical occasions: start and end of 1st, 2nd, 6th and 8th renewal periods.
Five replicates samples were analysed from each test concentration and one replicate from the control at each analytical occasion. At the end of the 6th renewal period (day 14) a single replicate was analysed from the 75.0 mg/L concentration as only one parent animal (i.e. one replicate out of ten) remained alive at this analytical occasion. At the 8th renewal this concentration was not more analysed (due to 100% mortality).

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method:
The test solutions used in the test was prepared by mechanical dispersion without using of any solubilising agent as follows:
At each water renewal period, a stock solution was first prepared by dissolving an amount of 0.15 g test item in 1500 mL dilution water (Elendt M4 medium) resulting a nominal concentration of 100 mg/L. The test solutions of the chosen test concentrations were prepared by appropriate diluting of this stock solution. After the formulation procedure the test animals were immediately introduced into test solutions at each water renewal period.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: Straus
- Source: Laboratory of Hydrobiology (Central Agricultural Office, Directorate of Plant-, and Soil Protection), 2100 Gödöllő, Kotlán S. u. 3. Hungary (Date of arrival to TOXI-COOP ZRT.: 17 January 2013)
- Age of parental stock: Less than 24 hours old and not the first brood progeny
- Breeding Conditions: The Daphnia are bred in the Laboratory of TOXI-COOP ZRT.
- Feeding during test: Yes
- Food type: Concentrated suspension of living algal cells of Raphidocelis subcapitata
- Amount: The amount of food supplied was based on the amount of organic carbon (C) provided to each parent animal. A total of 0.1 – 0.2 mg C/Daphnia/day was fed. Determination of the total organic carbon (TOC) content of algal suspension used for feeding is performed preferably annual.
- Frequency: Daily

ACCLIMATION:
The stock animals were maintained in same culture conditions (light, temperature, medium, feeding etc.) as that used during the exposure period, therefore additional acclimatisation to avoid stressing the parent animals prior to test was not necessary. Parent animals used in the test were not the first brood progeny.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

252 - 344 mg/L expressed in CaCO3

Test temperature:

Untreated control: 20.4 - 20.9 °C
Highest concentration: 20.5 - 21.0 °C

pH:

Untreated control: 7.44 - 8.45
Highest concentration: 7.29 - 8.60

Dissolved oxygen:

Untreated control: 5.89 - 8.27 mg/L
Highest concentration: 6.94 - 9.26 mg/L

Conductivity:

> 140 mg/L (expressed in CaCO3)

Nominal and measured concentrations:

Nominal: 3.0, 5.8, 10.9, 20.8, 39.5 and 75.0 mg/L.
Measured: The analytically measured test item concentrations remained within ± 20 % of the nominal concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers, appropriate size for holding 50-100 mL test medium.
- Aeration: The test vessels were not aerated
- Renewal rate of test solution: This reproduction test was carried out in a semi-static renewal system. The frequency of test solution renewal was three times per week (Monday, Wednesday and Friday). When the medium was renewed a second series of test vessels was prepared and the parent animals transferred to them by a pipette of suitable diameter. The volume of test medium transferred with the Daphnia was minimized.
- No. of organisms per vessel: 1 parent animal/test container
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

TEST MEDIUM / WATER PARAMETERS: Elendt M4 Medium according to OECD 202 and 211.

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16 h ligth/ 8 h dark
- Light intensity: 15 - 20 µE/m/s

EFFECT PARAMETERS MEASURED:
- Offspring: The living offspring produced by each parent animal were removed and counted daily from the appearance of the first brood. Aborted broods were counted and recorded.
- Mortality: The mortality among the parent animals was recorded daily.
- Growth Measurement: The length of the parent animals (i.e. body length excluding the anal spine) was measured at the end of the test.
- Other parameters: including time to production of first brood (and subsequent broods), number of broods per surviving parent animal, number of aborted broods were noticed.

TEST CONCENTRATIONS
- Range finding study:
In order to select appropriate test concentrations for the definitive test a non-GLP preliminary range-finding test was carried out to determine the approximate toxicity of the test item. In this preliminary test an acute toxicity test was extended to 13 day until the first broods appeared. Ten daphnids (divided into two replicates) were exposed in each test concentration (0.1, 1, 10 and 100 mg/L) and control.
- Test concentrations of range finding study: 0.1, 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: After 48 h exposure 80 % mortality was observed in the 100 mg/L concentration and no mortality were noticed in the lower concentrations of 0.1, 1 and 10 mg/L. Only the 10 mg/L concentration was further investigated for mortality and first juveniles.
Based on the results of the preliminary range-finding test six test concentrations in a geometric series with a spacing factor of 1.9 and one control was used in the main test. The following nominal concentrations were tested: 3.0, 5.8, 10.9, 20.8, 39.5 and 75.0 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

20.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

39.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

75 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

39.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

25.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: 95% CI: 9.7 – 35.1 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

44 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: 95% CI: 31.5 – 67.8 mg/L

Details on results:

- Observations on body length: At the end of the test, body length measurement of parent animals was performed. No significant difference compared to the control was observed in the two lowest concentrations of 3.0 and 5.8 mg/L. The length of parent animals remained alive at the end of the test reduced significantly at the concentrations 10.9, 20.8 and 39.5 mg/L. Due to the 100 % mortality measurement of this parameter was not applicable in the highest concentration of 75.0 mg/L.
- Other biological observations:
Abnormalities: Aborted broods were observed in only some cases during the test (in concentrations of 3.0, 5.8, 10.9 and 75.0 mg/L) and without concentration response pattern, therefore these abnormalities were considered to be due to natural causes rather than a test item effect.
- Mortality of control: Ten per cent mortality was observed for parent animals in the control group which is within the acceptability criteria.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: The 24h EC50 = 1.41 mg/L (95 % confidence limits: 1.19 – 1.68 mg/L)

Reported statistics and error estimates:

For the estimation of LOEC and NOEC values for effects of the test item on the reproductive output of Daphnia the mean value and standard deviation for reproductive output of each concentration was calculated and results were analysed by analysis of variance (ANOVA) and Dunnett’s test (Dunnett T3; α = 0.05) using SPSS software. Normal distribution and variance homogeneity was tested by Shapiro-Wilk and Levene test.
For the analysis of the mean body length of test animals the Dunnett’s test (Dunnett T3; α = 0.05) were used using SPSS software.
The EC× values (with 95 % confidence limits) for reproduction (number of juveniles) were calculated by Probit analysis using SPSS software.

Analytical results:

The measured concentrations of the test solutions were in the range of 84 – 115 % of the nominal during the test.

As all measured value remained within the range of ± 20 % of the nominal, the biological results are based on the nominal test item concentrations.

Measured data and the percentage of the nominal concentrations are detailed in Tables 1 -4.

Table 1: Diammonium peroxodisulphate (APS) concentrations measured in May 11-14 renewal period

Nominal concentration mg/L	Mean of the measured concentrations
	Start (May 11, 2018)		End (May 14, 2018)
	Concentration (mg/L)	% of the nominal	Concentration (mg/L)	% of the nominal
Control	not detected	-	not detected	-
3.0	3.07	102	3.22	107
5.8	6.07	105	6.34	109
10.9	11.3	103	12.6	115
20.8	20.6	99	22.1	106
39.5	38.9	99	42.2	107
75.0	74.1	99	76.4	102

Table 2: Diammonium peroxodisulphate (APS) concentrations measured in May 14-16 renewal period

Nominal concentration mg/L	Mean of the measured concentrations
	Start (May 14, 2018)		End (May 16, 2018)
	Concentration (mg/L)	% of the nominal	Concentration (mg/L)	% of the nominal
Control	not detected	-	not detected	-
3.0	2.92	97	3.43	114
5.8	5.37	93	5.96	103
10.9	10.6	97	12.5	115
20.8	19.8	95	22.4	108
39.5	37.2	94	42.6	108
75.0	69.2	92	82.6	110

Table 3: Diammonium peroxodisulphate (APS) concentrations measured in May 23-25 renewal period

Nominal concentration mg/L	Mean of the measured concentrations
	Start (May 23, 2018)		End (May 25, 2018)
	Concentration (mg/L)	% of the nominal	Concentration (mg/L)	% of the nominal
Control	not detected	-	not detected	-
3.0	3.16	105	3.05	102
5.8	5.76	99	5.98	103
10.9	10.5	97	11.3	104
20.8	19.4	93	20.3	98
39.5	35.0	89	39.3	100
75.0	63.0	84	72.7	97

Table 4: Diammonium peroxodisulphate (APS) concentrations measured in May 28-30 renewal period

Nominal concentration mg/L	Mean of the measured concentrations
	Start (May 28, 2018)		End (May 30, 2018)
	Concentration (mg/L)	% of the nominal	Concentration (mg/L)	% of the nominal
Control	not detected	-	not detected	-
3.0	3.18	106	3.08	103
5.8	6.15	106	6.00	104
10.9	11.6	106	11.4	105
20.8	21.3	102	21.0	101
39.5	38.0	96	39.7	101
Control	not detected	-	not detected	-

Biological results

Parent mortality:

The mortality among the parent animals was recorded daily.

Ten per cent mortality was observed for parent animals in the control group which is within the acceptability criteria.

The observed mortalities were within the normal range (≤ 20) in the test concentrations of 3.0, 5.8, 10.9, 20.8 and 39.5 mg/L. All mortalities occurred in these concentrations were accidental (due to technical incidence) or considered to be inadvertent mortality (i.e. non substance related mortality with no known cause) therefore these replicates were excluded from analysis of reproduction results.

All parent animals died during the test in the highest concentration of 75.0 mg/L which was considered to be a substance related toxic effect. Therefore, the results of this group based on reproduction (number of offspring) were included in the data analysis. The mortalities observed during the test are summarised in Table 5.

Offspring:

The offspring produced by each parent animal were removed and counted daily from the appearance of the first brood.

The mean number of living offspring produced by parent animals having survived at the end of the test was 64.1 in the control group.

No significant difference (Dunnett T3 test; α = 0.05) in offspring production was observed in the concentrations of 3.0, 5.8, 10.9 and 20.8 mg/L. Something higher values were observed in the three lowest concentrations of 3.0, 5.8 and 10.9 mg/L (mean numbers of offspring: 68.0, 67.4 and 68.9) and slightly lower value in the concentration of 20.8 mg/L (mean number of offspring: 58.0).

The offspring production was statistically significantly lower (Dunnett T3 test; α = 0.05) in the two highest concentration of 39.5 and 75.0 mg/L (mean numbers of offspring: 49.5 and 2.0).

The offspring produced during the test are summarised in table 6.

Table 5: Summary table of mortality (parental animals)

Concentrations[mg/L]	Number of treated animals	Number of died parent animals	Mortality (%)
Control	10	1	10
3.0	10	2	20
5.8	10	2	20
10.9	10	1	10
20.8	10	1	10
39.5	10	0	0
75.0	10	10	100

Table 6: Summary table of the juveniles

Concentrations[mg/L]	Mean number of juveniles	Mean number of juveniles in control %	SD	CV (%)
Control	64.1	100.0	6.8	10.6
3.0	68.0	106.1	13.4	19.7
5.8	67.4	105.1	14.1	20.9
10.9	68.9	107.5	12.4	18.0
20.8	58.0	90.5	12.2	21.1
39.5	49.5	77.2	10.5	21.2
75.0	2.0	2.9	2.3	113.0

Validity of the study:

- The mortality of parent animals (female Daphnia) did not exceed 20 % in the control group (observed mortality was 10 %). The accidental or inadvertent parental mortality was ≤ 20 % in each test concentrations.
- The mean number of live offspring per parent animal having survived in the control group at the end of the test was 64.1 (≥ 60), with variation coefficient of 10.62 (≤ 25 %).
All validity criteria were within acceptable limits and therefore the study can be considered as valid.

Validity criteria fulfilled:

yes

Conclusions:

Based on the results of this 21-day chronic toxicity study, the test item Diammonium peroxodisulphate (APS) had significant influence on the reproductive output of Daphnia magna. The determined NOEC and LOEC based on nominal concentrations for reproduction were 20.8 mg/L and 39.5 mg/L. An EC10 and EC50 of 25.9 mg/L (95% confidence limit: 9.7 - 35.1 mg/L) and 44.0 mg/L (95% confidence limit: 31.5 - 67.8 mg/L) for reproduction was oberseved, respectively. For mortality a NOEC vaule of 39.5 mg/L and a LOEC value of 75.0 mg/L was observed.

Executive summary:

The influence of the test item Diammonium peroxodisulphate (APS) on the reproductive output of Daphnia magna was observed in a 21-day chronic toxicity study according to OECD guideline 211, EU method C.20 and OPPTS 850.1300. In a semi static test system, young female Daphnia were exposed to aqueous test media containing the test item for 21 days at the nominal test item concentrations of 3.0, 5.8, 10.9, 20.8, 39.5 and 75.0 mg/L. The analytically measured test item concentrations remained within ± 20 % of the nominal, therefore the biological results are based on the nominal concentrations.

No significant inhibition in reproduction was noticed in the concentrations of 3.0, 5.8, 10.9 and 20.8 mg/L. The total number of living offspring per parent animal reduced significantly compared to the control in the two highest concentrations of 39.5 and 75.0 mg/L. No considerable mortality of parents (up to 20 %) was observed in the control and in the concentrations of 3.0, 5.8, 10.9, 20.8 and 39.5 mg/L and all parent animals died during the test in the highest concentration of 75.0 mg/L.

Based on the results of this 21-day chronic toxicity study, the test item had significant influence on the reproductive output of Daphnia magna.

The determined NOEC and LOEC based on nominal concentrations for reproduction were 20.8 mg/L and 39.5 mg/L. An EC10 and EC50 of 25.9 mg/L (95% confidence limit: 9.7 - 35.1 mg/L) and 44.0 mg/L (95% confidence limit: 31.5 - 67.8 mg/L) for reproduction was observed, respectively. For mortality a NOEC vaule of 39.5 mg/L and a LOEC value of 75.0 mg/L was observed.

Description of key information

Based on the results of this 21-day chronic toxicity study, the test item Diammonium peroxodisulphate (APS) had significant influence on the reproductive output of Daphnia magna. The determined NOEC and LOEC based on nominal concentrations for reproduction were 20.8 mg/L and 39.5 mg/L. An EC10 and EC50 of 25.9 mg/L (95% confidence limit: 9.7 - 35.1 mg/L) and 44.0 mg/L (95% confidence limit: 31.5 - 67.8 mg/L) for reproduction was oberseved, respectively. For mortality a NOEC value of 39.5 mg/L and a LOEC value of 75.0 mg/L was observed.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

25.9 mg/L

Additional information

The influence of the test item Diammonium peroxodisulphate (APS) on the reproductive output of Daphnia magna was observed in a 21-day chronic toxicity study according to OECD guideline 211, Eu method C.20 and OPPTS 850.1300. In a semi static test system, young female Daphnia were exposed to aqueous test media containing the test item for 21 days at the nominal test item concentrations of 3.0, 5.8, 10.9, 20.8, 39.5 and 75.0 mg/L. The analytically measured test item concentrations remained within ± 20 % of the nominal, therefore the biological results are based on the nominal concentrations.

No significant inhibition in reproduction was noticed in the concentrations of 3.0, 5.8, 10.9 and 20.8 mg/L. The total number of living offspring per parent animal reduced significantly compared to the control in the two highest concentrations of 39.5 and 75.0 mg/L. No considerable mortality of parents (up to 20 %) was observed in the control and in the concentrations of 3.0, 5.8, 10.9, 20.8 and 39.5 mg/L and all parent animals died during the test in the highest concentration of 75.0 mg/L.

Based on the results of this 21-day chronic toxicity study, the test item had significant influence on the reproductive output of Daphnia magna.

The determined NOEC and LOEC based on nominal concentrations for reproduction were 20.8 mg/L and 39.5 mg/L. An EC10 and EC50 of 25.9 mg/L (95% confidence limit: 9.7 - 35.1 mg/L) and 44.0 mg/L (95% confidence limit: 31.5 - 67.8 mg/L) for reproduction was oberseved, respectively. For mortality a NOEC vaule of 39.5 mg/L and a LOEC value of 75.0 mg/L was observed.