Distillates (coal tar), heavy oils

Toxicity to terrestrial plants

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference Type:

publication

Title:

Toxicity of eight polycyclic aromatic compounds to red clover (Trifolium pratense), ryegrass (Lolium perenne), and mustard (Sinapsis alba)

Author:

Sverdrup LE, Krogh PH, Nielsen T, Kjcr C, Stenersen J

Year:

2003

Bibliographic source:

Chemosphere, 53, 993-1003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 208 (Terrestrial Plants Test: Seedling Emergence and Seedling Growth Test)

Principles of method if other than guideline:

Comparative study including 4 aromatic and and 4 heteroaromatic compounds.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Phenanthrene

EC Number:

201-581-5

EC Name:

Phenanthrene

Cas Number:

85-01-8

Molecular formula:

C14H10

IUPAC Name:

phenanthrene

Details on test material:

- Name of test material (as cited in study report): Phenanthrene
Source: Sigma-Aldrich (Steinheim, Germany)
Purity: >96 %

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
PHYSICO-CHEMICAL PROPERTIES
- Vapour pressure: ~ 0.016 Pa (25 °C)
- Water solubility: ~ 1.3 mg/L (25 °C)
- log Pow: 4.5 - 4.6

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Initial concentration in test soil for verification of test-substance levels

Test substrate

Vehicle:

yes

Details on preparation and application of test substrate:

- Method of application to soil: Test substance dissolved in acetone, diluted from a stock solution:
250 ml acetone solution was mixed into 1.25 kg soil. Pure acetone was used for the control test. Solvent-free controls were also included.
- Vehicle: Acetone
- Evaporation of vehicle before use: The solvent was evaporated from the treated soil (spread on glass plates) in a fume head for 24 h.

Test organisms

1

Species:

Sinapis alba

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Mustard
- Plant family: Brassicaceae
- Variety: no data
- Source of seed: Ove Rassmussens Planteskole (Silkeborg, Denmark)

Prior to test start dameged/ discoloured seeds were rejected
Seeds of similar size were selected for the experiment

2

Species:

Trifolium pratense

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Red clover
- Plant family: Fabaceae
- Variety: no data
- Source of seed: DLF Trifolium (Randers, Denmark)

Prior to test start dameged/ discoloured seeds were rejected
Seeds of similar size were selected for the experiment

3

Species:

Lolium perenne

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Perennial ryegrass
- Plant family: Gramineae
- Variety: no data
- Source of seed: DLF Trifolium (Randers, Denmark)

Prior to test start dameged/ discoloured seeds were rejected.
Seeds of similar size were selected for the experiment.

Study design

Test type:

early seedling growth toxicity test

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

19 d

Post exposure observation period:

no data

Test conditions

Test temperature:

Night: 15 °C, day ~25 °C, sometimes higher

pH:

Soil pH: 6.2

Moisture:

Test soils were hydrated to 65 % of the water holding capacity with water (200 ml/kg soil).

Details on test conditions:

TEST SYSTEM
- Testing facility: Growth chamber placed in a green house
- Test container: Transparent cylinder made of hard plastics (35 cm high, inner diameter 9.5 cm), closed at the top and bottom with lids.
The upper lid was perforated with one hole.
- Amount of soil: 300 g wet weight per test container
- No. of seeds per container: 5
- No. of plants per replicate per dose: 5
- No. of replicates per treatment group: 4
- No. of replicates per control: 5
- No. of replicates per vehicle control: 5
- Plant density: ~71 cm2 / 5 seeds = ~14 cm2/seed; 300 g soil wet weight/5 seeds = 60 g/seed

All three species were tested simultaneously.

SOURCE AND PROPERTIES OF THE ARTIFICIAL SOIL:

Danish agricultural soil (Askov, Jutland): Sandy loam
- Coarse sand (0.2 – 2 mm) 38.4 %,
- fine sand (0.063 – 0.2 mm) 23.6 %,
- coarse silt (0.02 – 0.063 mm) 10.0 %,
- fine silt (0.002 – 0.02 mm) 12.3 %,
- clay (<0.002 mm) 13 %, humus 2.8 %
Organic carbon content: 1.6 %
Soil pH: 6.2
Density: 1.135 g/cm3
Cation exchange capacity: 8.14 meq/100 g

Pretreatment of the soil prior to use: Drying at 80 °C for 24 h, sieving: (2 mm mesh)

NUTRIENT MEDIUM (if used)
- Description:

GROWTH CONDITIONS
- Photoperiod: 16 h light, 8 h darkness alternately
- Light source: Cultivation lamps (400 W, 310 - 780 nm)
-Approximate photoflux density: 300 µE/m2/s on soil surface

- Day/night temperatures: Night: 15 °C, day ~25 °C, sometimes higher

EFFECT PARAMETERS MEASURED: Dry weight, fresh weight
Number of germinated seed by counting the seedlings that protruded above the soil surface

- Phytotoxicity rating/ harvest: 14 d after which 50 % of the seeds had emerged in the control samples

VEHICLE CONTROL PERFORMED: yes

Nominal and measured concentrations:

Nominal: 1, 10, 100, and 1000 mg/kg soil d.w.
Confirmation by analysis: 0.9, 9.9, 114, 1100 mg/kg soil d.w.

Results and discussion

Effect concentrations

Effect concentrations 1

Species:

Sinapis alba

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

ca. 13 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Remarks on result:

other: Estimation, related to 2 % organic carbon (standard)

Effect concentrations 2

Species:

Trifolium pratense

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

ca. 13 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Remarks on result:

other: Estimation, related to 2 % organic carbon (standard)

Effect concentrations 3

Species:

Sinapis alba

Duration:

21 d

Dose descriptor:

other: EC20

Effect conc.:

77 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Remarks on result:

other: 95% C.I. 41 - 110 mg/kg soil dw

Effect concentrations 4

Species:

Sinapis alba

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

480 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Effect concentrations 5

Species:

Trifolium pratense

Duration:

21 d

Dose descriptor:

other: EC20

Effect conc.:

37 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Remarks on result:

other: 95% C.I. 22 -52 mg/kg soil dw

Effect concentrations 6

Species:

Trifolium pratense

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

79 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Effect concentrations 7

Species:

Lolium perenne

Duration:

21 d

Dose descriptor:

other: EC20

Effect conc.:

300 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Effect concentrations 8

Species:

Lolium perenne

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

760 mg/kg soil dw

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

- fresh weight

Details on results:

No effect on seed germination observed at any exposure level: => LC50 supposed >> 1000 mg/kg soil d.w.
The NOEC values are estimates, as no effects data below EC20 were documented:
The results of the study indicate that NOECs for the tested PAHs to terrestrial plants is 10 mg/kg dw soil.
(except for fluoranthene which is supposed to have a NOEC of approx. 100 mg/kg dw.)

Reported statistics and error estimates:

The LC50 was determined using the Probit method (with SAS/STAT software).
EC20- and EC50 values were estimated by linear interpolation of the dose-response curve, confidence intervals by the regression procedure of SAS/STAT.
NOECs were determined using ANOVA and Dunnett´s procedure (at 5-% significance level).