Registration Dossier

Administrative data

Endpoint:
toxicity to terrestrial plants: long-term
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
June 04, 2007 - July 02, 2007
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Rationale for read-across: in the environment, lime substances rapidly dissociate or react with water. These reactions, together with the equivalent amount of hydroxyl ions set free when considering 100mg of the lime compound (hypothetic example), are illustrated below: Ca(OH)2 <-> Ca2+ + 2OH- 100 mg Ca(OH)2 or 1.35 mmol sets free 2.70 mmol OH Ca(OH)2 + 2Ca2SiO4 +9CaCO3 + 13H2O <-> 14Ca2+ + 2SiO2 + 9CO2 + 28OH- 100 mg “Reaction mass of limestone and dicalcium silicate” or 0.08 mmol sets free 2.24 mmol OH- has to be noted that CO32- is not expected to directly release two hydroxyl ions under most environmental conditions (depends on CO2 concentrations and pH) and this is therefore a worst case assumption. From these reactions it is clear that the effect of "Reaction mass of limestone and dicalcium silicate" will be caused either by calcium or hydroxyl ions. Since calcium is abundantly present in the environment and since the effect concentrations are within the same order of magnitude of its natural concentration, it can be assumed that the adverse effects are mainly caused by the pH increase caused by the hydroxyl ions. Furthermore, the above mentioned calculations show that the base equivalents are within a factor 2 for lime (chemical), hydraulic and calcium hydroxide. As such, it can be reasonably expected that the effect on pH of "Reaction mass of limestone and dicalcium silicate" is comparable to calcium hydroxide for a same application on a weight basis. Consequently, read-across from calcium hydroxide to "Reaction mass of limestone and dicalcium silicate" is justified.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 208 (Terrestrial Plants Test: Seedling Emergence and Seedling Growth Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
IUPAC name: calcium dihydroxide
Product type: Precal 50 S
Active ingedrient / purity: calcium dihydroxide / 98.2% (analysed)
Batch No.: 7025
Received: 2007-01-30
Expiry date: January 2009
Appearance: solid, white powder
Water solubility (20°C): 1.26 g/l
Storage conditions: room temperature, under dry conditions
Stability: at least for 2 years when stored at recommended conditions

Sampling and analysis

Analytical monitoring:
no
Details on sampling:
On day 21 after 50% seedling emergence, soil samples are taken for pH measurements.

Test substrate

Vehicle:
no
Details on preparation and application of test substrate:
TEST SOIL
Origin: agricultural soil from site Gerichshain (batch G 01/2007), stored for at least 1 year before used in the test
Soil type: sandy loam according to "AG Bodem" of BBA 1994, loam according to USDA
pH value (CaCl2): 5.9 (ISO 10390)
C(org): 0.9%
Humus content: 1.5%
Water holding capacity: 38.8 g/100 g dry soil
Particle size: 9.9% < 0.002 mm (clay), 45.9% between 0.002 and 0.063 mm (silt) and 44.3% between 0.063 and 2.0 mm (sand)
No pesticides or fertilisers were applied on the origin plot of the used soil for at least 5 years because the plot was fallow land

Test organisms

open allclose all
Species:
Beta vulgaris
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Common name: sugar beet
Variety: Achat
PSeeds prchased from: Strube-Dieckmann GmbH & Co. KG, Söllingen
Batch: SD04-04-07-19
Determined germination rate: 94%
Species:
Brassica napus
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Common name: oilseed rape
Variety: Express
Seeds purchased from: Saaten-Union GmbH, Isernhagen
Batch: SU03-04-07-17
Determined germination rate: 96%
Species:
other: Spinacia oleracea
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Common name: spinach
Variety: Lavewa
Seeds purchased from: N.L. Chrestensen, Erfurt
Batch: 455815
Determined germination rate: 94%
Species:
Pisum sativum
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Common name: pea
Variety: Maxigolt
Seeds purchased from: Dehner Gartencenter, Taucha
Batch: 2924
Determined germination rate: 90%
Species:
Triticum aestivum
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
Common name: wheat
Variety: Tommi
Seeds purchased from: Saaten-Union GmbH, Isernhagen
Batch: SU03-04-07-18
Determined germination rate: 98%
Species:
other: Allium porrum
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
Common name: leek
Variety: Genita
Seeds purchased from: Dehner Gartencenter, Taucha
Batch: 1665
Determined germination rate: 88%

Study design

Test type:
early seedling growth toxicity test
Study type:
laboratory study
Substrate type:
artificial soil
Limit test:
no
Total exposure duration:
21 d
Remarks:
21 days after 50% seedling emergence in the control group

Test conditions

Test temperature:
16-36°C (short-term temperature over 40°C)
pH:
pH test soil: 5.9
pH at day 0: 5.9 - 9.4
pH at end test: 5.7 - 9.0
Moisture:
Relative humidity: 25-92% (short-term relative humidity under 45%)
Details on test conditions:
PREPARATION
The test item was incorporated directly into the soil by mixing with the soil in a mixing machine.
TEST CONDITIONS
Test pot: plastic flower pot (Ø 15 cm), amount 1.0 kg
Number of plants/pot: 3 for Pisum sativum, 4 for Brassica napus, Beta vulgaris and Spinacia oleracea and 5 for Triticum aestivum and Allium porrum.
Number of pots: 14 for Pisum sativum, 10 for Brassica napus, Beta vulgaris and Spinacia oleracea and 8 for Triticum aestivum and Allium porrum.
Number of seeds/treatment: 40-42
Fertilising: Pflanzenvollnahrung (Dehner Gartenzentrum)
Fertilizer nutrients: 4% N, 3% P2O5 and 3% K2O
Fertilizer dressing: once, 7 days after germination
Fertilizer solution: 100 ml/pot
Irrigation: daily with 40 ml tap water (room temperature, pH 7.3 and conductivity 580 μs/cm)
CLIMATIC TEST CONDITIONS
Relative humidity: 25-92% (short-term relative humidity under 45%)
Illumination: light period: 16 h (including 6h HQL-light)
Nominal and measured concentrations:
Nominal concentrations: 0, 0.51, 1.08, 2.27, 4.76 and 10.0 g test item/kg soil dry weight.
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Species:
other: Allium porrum
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
5.64 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
seedling emergence
Remarks on result:
other: NOEC for seedling emergence: 2.27 g/kg dw
Species:
other: Allium porrum
Duration:
21 d
Dose descriptor:
LC50
Effect conc.:
10.83 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: seedling survival
Species:
other: Allium porrum
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
3.53 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Remarks on result:
other: NOEC: 2.27 g/kg dw; LOEC: 4.76 g/kg dw
Species:
Beta vulgaris
Duration:
21 d
Dose descriptor:
other: EC50 and LC50
Effect conc.:
> 10 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: seedling emergence (7 days) and survival (21 days)
Remarks on result:
other: NOEC for seedling emergence: 4.76 g/kg dw
Species:
Beta vulgaris
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
3.8 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Remarks on result:
other: NOEC: 1.08 g/kg dw; LOEC: 2.27 g/kg dw
Species:
Brassica napus
Duration:
21 d
Dose descriptor:
other: EC50 and LC50
Effect conc.:
> 10 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: seedling emergence (day 7) and survival (day 21)
Remarks on result:
other: NOEC for seedling emergence: 10 g/kg dw
Species:
Brassica napus
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
4.15 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Remarks on result:
other: NOEC: 1.08 g/kg dw; LOEC: 2.27 g/kg dw
Species:
Pisum sativum
Duration:
21 d
Dose descriptor:
other: EC50 and LC50
Effect conc.:
> 10 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca(OH)2)
Basis for effect:
other: seeding emergence (7 days) and survival (21 days)
Remarks on result:
other: NOEC for seedling emergence: 4.76 g/kg dw
Species:
Pisum sativum
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
6.18 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Remarks on result:
other: NOEC: 2.27 g/kg dw; LOEC: 4.76 g/kg dw
Species:
other: Spinacea oleracea
Duration:
21 d
Dose descriptor:
other: EC50 and LC50
Effect conc.:
> 10 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: seedling emergence (7 days) and survival (21 days)
Remarks on result:
other: NOEC for seedling emergence: 4.76 g/kg dw
Species:
other: Spinacea oleracea
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
2.67 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Remarks on result:
other: NOEC: 1.08 g/kg dw; LOEC: 2.27 g/kg dw
Species:
Triticum aestivum
Duration:
21 d
Dose descriptor:
other: EC50 and LC50
Effect conc.:
> 10 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: seedling emergence (day 7) and survival (day 21)
Remarks on result:
other: NOEC for seedling emergence: 10 g/kg dw
Species:
Triticum aestivum
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
5.14 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Remarks on result:
other: NOEC: 2.27 g/kg dw; LOEC: 4.76 g/kg dw
Species:
other: Allium porrum
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
2.27 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Triticum aestivum
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
2.27 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Brassica napus
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
1.08 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Beta vulgaris
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
1.08 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Species:
other: Spinacia oleracea
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
1.08 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Pisum sativum
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
2.27 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
other: Allium porrum
Duration:
21 d
Dose descriptor:
LOEC
Effect conc.:
4.76 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Triticum aestivum
Duration:
21 d
Dose descriptor:
LOEC
Effect conc.:
4.76 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Brassica napus
Duration:
21 d
Dose descriptor:
LOEC
Effect conc.:
2.27 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Beta vulgaris
Duration:
21 d
Dose descriptor:
LOEC
Effect conc.:
2.27 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
other: Spinacia oleracea
Duration:
21 d
Dose descriptor:
LOEC
Effect conc.:
2.27 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Species:
Pisum sativum
Duration:
21 d
Dose descriptor:
LOEC
Effect conc.:
4.76 g/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(Ca (OH)2)
Basis for effect:
other: shoot fresh weight
Details on results:
Seedling emergence in the control: ≥ 70%
Mean survival of emerged control seedlings: ≥ 90%
Seedling do not exhibit visible phytotoxic effects in the control and the plants exhibit only normal variation growth and morphology for that particular species.
Upon addition of the test item to the soil, a rapid increase in soil pH from 6.1 to 6.9, 7.7, 8.4, 8.9 and 9.4 respectively was observed. The soil pH decreased again during the course of the study. Additional pH
measurements of soil samples were analysed without air-drying. The results indicate that the initial soil pH was underestimated as a result of carbonisation of the test item during air-drying of the soil
samples.
Growth inhibition was observed in all plants especially at 4.76 and 10 g/kg dw.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The results of the test indicate that of the six crop species tested, the dicotyledonae Brassica napus, Beta vulgaris and Spinacia oleracea and the monocytyledonae Allium porrum were most sensitive to the effects of Calcium dihydroxide (hydrated lime). Survival after seedling emergence (LC50) was only affected in the monocotyledonae Allium porrum.
Upon addition of the test item to the soil, a dose-dependent increase in soil pH was observed. In the course of the study, the pH value decreased. The increase in pH value of the soil after addition of Calcium dihydroxide is considered to determine the toxicity to plants.