Reaction mass of cobalt sulphide and nickel sulphide and trinickel disulphide

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

ISO 11268-2 (Effects of Pollutants on Earthworms. 2. Determination of Effects on Reproduction)

Deviations:

no

Principles of method if other than guideline:

not applicable

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Cobalt dichloride

EC Number:

231-589-4

EC Name:

Cobalt dichloride

Cas Number:

7646-79-9

Molecular formula:

Cl2Co

IUPAC Name:

cobalt(2+) dichloride

Details on test material:

- Name of test material (as cited in study report): CoCl2.6H2O
- source: VVWR, Belgium
- Other: No other parameters reported

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

To confirm the nominal cobalt concentrations in the soil, soils were digested in hot acid (HCI:HN03, 1:5 v/v, microwave heating)

Test substrate

Vehicle:

no

Details on preparation and application of test substrate:

All the soils were thoroughly mixed with concentrations of CoCL2.6H2O and moisture content was between 50 and 60% of water holding capacity (WHC). After spiking, samples were allowed to equilibrate for one week under the same conditions as those used for the toxicity tests.

Test organisms

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: earthworm
- Source: Blades Biological (Cowden, UK)
- Age at test initiation (mean and range, SD): adult with fully developed clitellum
- Weight at test initiation (mean and range, SD): 400-700mg ww

ACCLIMATION
not reported

Study design

Study type:

laboratory study

Substrate type:

natural soil

Limit test:

no

Total exposure duration:

28 d

Post exposure observation period:

the number of worms and cocoons was determined after washing the soil through a 1 mm sieve

Test conditions

Test temperature:

20 ± 1°C

pH:

4.3-7.5

Moisture:

50-60% of water holding capacity

Details on test conditions:

10 adult worms with a fully developed clitellum, were exposed to test jar containing 500g soils (wet weight). At the start of the test, 2 % (dry weight) finely ground cow dung was supplied. At the end of the tests (day 28), the number of worms and cocoons was determined after washing the soil through a 1 nun sieve. During exposure, all test vessels were kept at 20 ± 1 DC and a lightdark cycle of 16:8 at 400 - 800 lux. Soil moisture content (50 - 60 WHC) was adjusted twice a week by replenishing weight loss with the appropriate amount of deionised water. four to five replicates. Test jars were monitored daily to visually assess possible behavioural changes of the organisms.

TEST SYSTEM
- Test container (material, size): jar
- Amount of soil or substrate: 500 g ww
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
The soils tested were 10 natural soils exhibiting large variance in soil characteristics. see table 1 below.

OTHER TEST CONDITIONS
- Photoperiod: 16/8 light/dark
- Light intensity: 400-800 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : reproduction

VEHICLE CONTROL PERFORMED: no

TEST CONCENTRATIONS
The concentrations of cobalt (added as CoCh.6H20 , VWR, Belgium) were chosen in logarithmic series. The ranges of concentrations were selected based on (1) results of cobalt toxicity in two artificial soils OECD and LUF A.2 to E. albidus (Lock et aI. , 2006) and of the range finding tests 6 with three soils (Kasterlee, bcuven and Brecy) using E. fetida; ana \2) the linear relationship between metal toxicity (expressed as ECso) and the Cation Exchange Capacity (CEC) of the soils observed in previous studies (Lock et ai., 2003 ; Van Eeckhout et ai., 2005).

Nominal and measured concentrations:

not reported

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

56 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Athens soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 27-113

Effect concentrations 2

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

57 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Jyndevad soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 21.9-148

Effect concentrations 3

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

201 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co on Kasterlee soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 124-327

Effect concentrations 4

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

122 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Aluminusa soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 59-244

Effect concentrations 5

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

100 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Woburn soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 42-216

Effect concentrations 6

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

130 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Sidney soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 72-231

Effect concentrations 7

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

426 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Souli II soil

Basis for effect:

reproduction

Remarks on result:

other: 95% CL: 310-584

Effect concentrations 8

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

385 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Brecy soil

Basis for effect:

reproduction

Remarks on result:

other: 955 CL: 228-637

Effect concentrations 9

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

163 mg/kg soil dw

Nominal / measured:

meas. (not specified)

Conc. based on:

other: added Co in Leuven soil

Basis for effect:

reproduction

Remarks on result:

other: No reliable EC10 available, NOEC used instead

Details on results:

not reported

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

From the obtained concentration-response relationships, the EC50s and ECl0s (with 95% confidence limits) were calculated using the log-logistic response model (Haanstra et ai. , 1995). k y = l+(~JS X50 Where y = response of measured endpoint (e.g. number of juveniles or cocoons) k = response of measured endpoint at x = 0 s = slope parameter x = concentration (on a linear scale) Xso = ECso (median effective concentration) 9 The above mentioned model is re-parameterized to estimate both ECso and ECIO together in one run of the program: k Where y = response of measured endpoint (e.g. number of juveniles or cocoons) k = response of measured endpoint at x = 0 x = concentration (on a linear scale) Xso = ECso (median effective concentration) x)O = ECso (10% effective concentration) Model fitting and the calculations of the 95% confidence limits was carried out using LevenbergMarquardt (Levenberg, 1944; Marquardt, 1963), which is included in the Statistica 6.0 Software (Statsoft, Tulsa, OK). Comparison among ECso values based on the 95% confidence limits was performed following procedure described in Sprague and Fogels (1977). Reproduction of F candida, E. fetida and E. albidus after 28 or 42 days of exposure were statistically compared with those in the control soils using analysis of variance (ANOV A) followed by the Dunnett-test. When the assumption of normality or homogeneity of variance was not met, a non parametric analysis (Mann Whitney U-tests) was applied. Results of these analyses are expressed as p-values, with p < 0.05 were considered significant. These analyses were used to derive the No Observed Effect Concentration (NOEC) and Lowest Observed Effect Concentration (LOEC) values for the different soils. The relationship between the toxicity data (NOEC, EClOs and ECsos) and the soil parameters were investigated using linear regression analysis (Statistica 6.0).

Any other information on results incl. tables

According to REACH guidance Chapter R. 10 (Table R.10 -1) EC 10 values are used preferentially for PNEC derivation and therefore NOEC values are only presented as supporting information. However, one NOEC value is used for PNEC derivation since the EC10 was not reliable.

Duration	Endpoint	Effect Conc.	Nominal/Measured	Conc.based on	Basis for effect
28 d	NOEC	196 mg/kg soil dw	meas. (not specified)	other: total Co in Kasterlee soil	reproduction
28 d	NOEC	170 mg/kg soil dw	meas. (not specified)	other: total Co in Leuven soil	reproduction
28 d	NOEC	370 mg/kg soil dw	meas. (not specified)	other: total Co in Brecy soil	reproduction
28 d	NOEC	88 mg/kg soil dw	meas. (not specified)	other: total Co in Jyndevad soil	reproduction
28 d	NOEC	181 mg/kg soil dw	meas. (not specified)	other: total Co in Aluminusa soil	reproduction
28 d	NOEC	179 mg/kg soil dw	meas. (not specified)	other: total Co in Woburn soil	reproduction
28 d	NOEC	573 mg/kg soil dw	meas. (not specified)	other: total Co in Souli II soil	reproduction
28 d	NOEC	<62 mg/kg soil dw	meas. (not specified)	other: total Co in Atherns soil	reproduction
28 d	NOEC	162 mg/kg soil dw	meas. (not specified)	other: total Co in Sidney soil	reproduction

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In total, 9 results were selected for PNEC derivation: between 56 mg added Co/kg (Athens soil) and 385 mg added Co/kg (Souli II soil).

Executive summary:

not applicable