Ashes (residues), plant

Toxicity to terrestrial plants

Administrative data

Endpoint:

toxicity to terrestrial plants: short-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

ISO 11269-2 (Soil quality - Determination of the effects of pollutants on soil flora - Part 2: Effects of contaminated soil on the emergence and early growth of higher plants)

Version / remarks:

(1995)

GLP compliance:

no

Remarks:

Test were performed to fulfill the requirements of 2000/532/EG and Dir 91/689/EEC, GLP was not required for that purpose

Test material

Test material information

1

Reference substance name:

Ashes (residues)

EC Number:

268-627-4

EC Name:

Ashes (residues)

Cas Number:

68131-74-8

Molecular formula:

Not available / UVCB substance

IUPAC Name:

FBC Ash (residues of coal combustion in fluidized bed combustion boilers)

Test material form:

solid: particulate/powder

Details on test material:

Wirbelschichtasche (WSA)

Specific details on test material used for the study:

mg/kg (in solid FBC ash samples)
Arsenic (As) 10.8
Cadmium, Cd 0.93
Cobalt (Co) 8.17
Chromium (Cr) 47.4
Copper (Cu) 140
Molybdenum (Mo) 16.7
Nickel (Ni) 27.3
Lead (Pb) 65.5
Antimony (Sb) 9.34
Selenium (Se) 5.76
Vanadium (V) 104
Zinc (Zn) 415

Sampling and analysis

Analytical monitoring:

no

Test substrate

Details on preparation and application of test substrate:

In these experiments, the respective test organisms were exposed to a series of dilutions (=mixtures of the sample to be tested with a control material). Each dilution stage was characterized by its G value (new designation: LID value = Lowest Ineffective Dilution (ISO 2006)), i.e. the reciprocal dilution factor (e.g. G value = 4 corresponds to a mixture of 25% sample plus 75% control material)

Taking into account the moisture of the samples and the standard soil, 7200 g dry weight of the mixture were prepared per dilution stage
- each testing vessel was filled with 900 g (± 10 g) of this mixture

Test organisms

1

Species:

Brassica napus

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

Brassica napus (variety: LIFORUM, LUFA, Speyer)
The seeds were stored in the dark at 4°C between trials.

2

Species:

Avena sativa

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

Avena sativa (variety: ARAGON, Saat-Union GmbH, Iserhagen)
The seeds were stored in the dark at 4°C between trials.

Study design

Test type:

early seedling growth toxicity test

Study type:

laboratory study

Substrate type:

artificial soil

Remarks:

LUFA standard soil 2.3

Limit test:

no

Total exposure duration:

15 d

Remarks:

starting on the day when at least 50% of the seeds had germinated in the control vessels (Day 0)

Test conditions

Test temperature:

23 ± 3°C

Moisture:

40-50%

Details on test conditions:

TEST SYSTEM
- Test container (type, material, size): Plastic cups (Göttinger plant pots, 120×120×120 mm)
- Amount of soil: Taking into account the moisture of the samples and the standard soil, 7200 g dry weight of the mixture were prepared per dilution stage
- each testing vessel was filled with 900 g (± 10 g) of this mixture
- Method of seeding: Sowing was carried out using tweezers at a depth of about 1 cm. After the emergence assessment, the seedlings per replica were thinned out to 5 representative representatives distributed evenly over the pot.
- No. of seeds per container: 10
- No. of plants (retained after thinning): 5
- No. of replicates per treatment group: 4
- No. of replicates per control: 4


SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
LUFA standard soil 2.3


NUTRIENT MEDIUM (if used)
Substral plant mutrient medium (Scotts Celaflor GmbH and Co. KG, Ingelheim); Dilution: 70 mL fertilizer in 10 L deionized water

GROWTH CONDITIONS
- Photoperiod: , the light/dark phase was 16/8 h.
- Light intensity and quality: The light intensity was 13000 ± 2000 lx
- Day/night temperatures: 23 ± 3°C
- Relative humidity (%): 40-50%
- Watering regime and schedules: The test vessels were individually placed in reservoirs filled with 100 mL deionized water so that the test mixtures could soak up the water
- Water source/type: deionized water
- Volume applied: 100 mL
- Interval of applications: one time
- Method of application: the test vessels were placed in the reservoirs


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

The plants were scored at the end of the test, the end point "fresh weight" was determined. In addition, the above-ground shoot length and optical abnormalities such as chlorosis, necrosis and deformation were recorded, which provide information about possible phytotoxicity.

VEHICLE CONTROL PERFORMED: no

TEST CONCENTRATIONS
- Range finding study: In the first step, a preliminary test with the dilution levels 1/1, 1/2, 1/4, 1/8 and 1/16 and one or two replicates each was carried out with test substance. The preliminary test must be repeated in order to be able to determine suitable dilution levels for the dose-effect test

- Test concentrations:
- Results used to determine the conditions for the definitive study: Based on the results of these preliminary tests, full dose-response tests according to ISO 11269-2 (1995) were set up in a second step, the samples were tested with LUFA standard soil 2.3 in three to five dilution stages mixed: 1/64; 1/32; 1/16; 1/8; 1/4

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Species:

Avena sativa

Duration:

15 d

Dose descriptor:

EC50

Effect conc.:

> 66.7 other: g/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Effect concentrations 2

Species:

Brassica napus

Duration:

15 d

Dose descriptor:

EC50

Effect conc.:

66.7 - 142.8 other: g/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Details on results:

see table 1 and table 2 for individual growth inhibition

Any other information on results incl. tables

Tab. 1: Weight inhibition in the plant growth tests with Avena sativa (oats); Effective threshold: 30%

Dilution level	1/64 1,6 %	1/32 3,1 %	1/16 6,25 %	1/ 8 12,5 %	1/4 25 %
reduction of fresh weight (%)	8,2	-5,5	27,9	-	-

 

Tab. 2 Weight inhibition in the plant growth tests with Brassica napus (rapeseed); Effective threshold: 30%

 

 

Dilution level	1/64 1,6 %	1/32 3,1 %	1/16 6,25 %	1/ 8 12,5 %	1/4 25 %
reduction of fresh weight (%)	-11,3	-30,2	32,9	81,1	95,6

 

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of this study, the EC50 for growth rate was not calculated but determined to lie between EC50 = 66.7 - 142.9 g/kg soil dw for Brassica napus and for Avena sativa: EC50 > 66.7 g/kg soil dw.

Executive summary:

The toxicity of Ashes from fluidized bed combustion coal fired power stations with and without co-combustion of secondary fuels (FBC Ash) to plants was assessed by Römbke (2008) according to the ISO 11269-2 Soil quality — Determination of the effects of pollutants on soil flora — Part 2: Effects of chemicals on the emergence and growth of higher plants (1995). During an exposure period of 15 days the plant species Avena sativa (Monocotyledonae) and Brassica napus (Dicotyledonae) were exposed to different concentrations of FBC ash in soil. The test starting on the day when at least 50% of the seeds had germinated in the control vessels (Day 0).

The plants were scored at the end of the test, the end point "fresh weight" was determined. In addition, the above-ground shoot length and optical abnormalities such as chlorosis, necrosis and deformation were recorded, which provide information about possible phytotoxicity.

Under the conditions of this study, the EC50 for growth rate was not calculated but determined to lie between EC50 = 66.7 - 142.9 g/kg soil dw for Brassica napus and for Avena sativa: EC50 > 66.7 g/kg soil dw.