Registration Dossier

Administrative data

Endpoint:
toxicity to terrestrial plants: long-term
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Jan 2, 2004 to July 13, 2005
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: study performed according to international guidelines and GLPS using commercial product and published in the literature.

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
2005
Reference Type:
publication
Title:
Terrestrial toxicity evaluation of decabromodiphenyl ethane on organisms from three trophic levels.
Author:
Hardy et al.
Year:
2011
Bibliographic source:
Ecotoxicol Environ Saf 74(4):703-10.
Reference Type:
publication
Title:
Results of terrestrial and aquatic studies on the brominated flame retardant, decabromodiphenyl ethane, a.k.a. Ethane 1,2 bis(pentabromophenyl)
Author:
Hardy et al.
Year:
2009
Bibliographic source:
SETAC Annual Meeting, Nov 2009, New Orleans, LA

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EPA OPPTS 850.4100 (Terrestrial Plant Toxicity Tier I (seedling emergence))
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 850.4225 (Seedling Emergence Tier II)
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 208 (Terrestrial Plants Test: Seedling Emergence and Seedling Growth Test)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
The test substance was 97.53% DBDPEthane with 2.08% Nonabromodiphenyl Ethane as impurity.

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Test article concentrations were determined in soil at study initiation.

Test substrate

Vehicle:
no

Test organisms

open allclose all
Species:
Zea mays
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
The plant test species and source were as follows: corn (Zea mays) and Soybean (Glycine max), Johnny’s Selected Seeds, Albion, ME; onion (Allium cepa), Henry Field’s Seed and Nursery, Aurora, IN; ryegrass (Lolium perenne) and tomato (Lycopersicon esculentum), Meyer Seed Co., Baltimore, MD; and cucumber (Cucumis sativa), Park Seed Wholesale, Greenwood, SC. Seeds were not treated with fungicides, insecticides or repellents prior to test initiation.
Species:
Cucumis sativus
Plant group:
Dicotyledonae (dicots)
Species:
Glycine max (G. soja)
Plant group:
Dicotyledonae (dicots)
Species:
Lolium perenne
Plant group:
Monocotyledonae (monocots)
Species:
Lycopersicon esculentum
Plant group:
Dicotyledonae (dicots)
Species:
Allium cepa
Plant group:
Monocotyledonae (monocots)

Study design

Test type:
seedling emergence toxicity / vegetative vigour test
Study type:
laboratory study
Substrate type:
artificial soil
Limit test:
no
Total exposure duration:
21 d
Post exposure observation period:
no

Test conditions

Test temperature:
see below
pH:
see below
Moisture:
see below
Details on test conditions:
see below
Nominal and measured concentrations:
Nominal: 0, 391, 781, 1,563, 3,125 and 6,250 mg/ kg dry soil
Measured:
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Species:
Zea mays
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
6 250 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: seedling emergence and growth
Species:
Cucumis sativus
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
3 125 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: survival
Species:
Allium cepa
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
1 563 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: height, dry weight
Species:
Lolium perenne
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
6 250 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: seedling emergence and growth
Species:
Glycine max (G. soja)
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
6 250 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: seedling emergence and growth
Species:
Lycopersicon esculentum
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
3 125 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: Height, dry weight
Details on results:
In the seedling emergence tests, the measured concentration of DBDEthane in the matrix blank was < LOQ (100 mg/kg). The matrix fortification samples at 350 and 6500 mg/kg ranged from 89-100% of nominal with the lowest recovery at the highest dose level. DBDPEthane was not detected in the control soil (
Inadequate emergence of control onion and tomato seedlings resulted in a repeated test in these two species; final results represent the repeated test. The irrigation tube supplying water to one tomato replicate (1,563 mg/kg) was inadvertently removed from the tray during the test so that seedlings were not watered. This replicate was dropped from statistical analysis of height and dry weight due to non-treatment-related reductions.

No effects were observed on any endpoint in corn, ryegrass and soybean. Any reductions in mean height and weight relative to the control mean were not dose-responsive and incidental to treatment. At 6,250 mg/kg, survival in cucumbers was 18% lower than the controls (p<0.05). Onion mean height was reduced 22 and 24% relative to the control in the 3,125 and 6,250 mg/kg groups, respectively (p<0.05). Weight was also reduced by 32 and 30% at these dose levels. Height and dry weight of tomatoes were reduced at the high dose (p<0.5).


Reported statistics and error estimates:
Seedling emergence, survival, mean shoot weight, and seedling height were compared using the General Linear Model procedure of SAS version 8 and Dunnett’s post-test (p<0.05). Seedling emergence was defined as the number of emerged seedlings per ten planted seeds in each pot. Survival was the number of living seedlings in each pot per ten planted seeds. Mean shoot weight was the average dry shoot weight of living emerged seedlings in each pot. Height was the average height of living emerged seedlings in each pot. The NOEC and LOEC for condition and growth were also determined. The LOEC was the lowest concentration showing an adverse effect on a variable of interest, whereas the NOAEC is the maximum test concentration showing no adverse phytotoxic effects. Dunnett’s test was used to aid in establishing these concentration by determining which treatment groups differed significantly from the control group.

Any other information on results incl. tables

In the seedling emergence tests, the measured concentration of DBDEthane in the matrix blank was < LOQ (100 mg/kg). The matrix fortification samples at 350 and 6500 mg/kg ranged from 89-100% of nominal with the lowest recovery at the highest dose level.   DBDPEthane was not detected in the control soil (<LOQ of 100 mg/kg). Soil concentrations at test initiation were 94-102%, 94-101%, 93-110%, 86-99%, and 75-97% of nominal in the 391, 781, 1,563, 3,125 and 6,250 mg/kg groups, respectively. The range of soil concentrations at each dose level is derived from measured concentrations in the original corn, soybean, ryegrass, and cucumber tests and the repeated onion and tomato tests that experienced low control emergence.  

The temperature, relative humidity (%RH) and photosynthetically active radiation (PAR) (mean ± standard deviation) experienced by the corn, soybean, cucumber and ryegrass seedlings over the course of the study were 20.78 ± 1.08ºC, 29.37 ± 10.48 % and 8.3 ±0.7 moles, respectively. Environmental conditions experienced by tomato seedlings were 26.04 ± 1.85ºC, 63.37 ± 7.34 %RH, and 8.8 ± 1.3 moles PAR. Onion experienced 25.57 ± 1.60ºC, 73.52 ± 8.20 %RH, and 14.0 ± 1.4 moles PAR.

Inadequate emergence of control onion and tomato seedlings resulted in a repeated test in these two species; final results represent the repeated test. The irrigation tube supplying water to one tomato replicate (1,563 mg/kg) was inadvertently removed from the tray during the test so that seedlings were not watered. This replicate was dropped from statistical analysis of height and dry weight due to non-treatment-related reductions.   

No effects were observed on any endpoint in corn, ryegrass and soybean. Any reductions in mean height and weight relative to the control mean were not dose-responsive and incidental to treatment. At 6,250 mg/kg, survival in cucumbers was 18% lower than the controls (p<0.05). Onion mean height was reduced 22 and 24% relative to the control in the 3,125 and 6,250 mg/kg groups, respectively (p<0.05). Weight was also reduced by 32 and 30% at these dose levels. Height and dry weight of tomatoes were reduced at the high dose (p<0.5). 

Effects of DBDPEthane on seedling emergence, survival, height, and dry weight in a 21-d seedling emergence test with corn (Z. mays).

Test Concentration (mg/kg)

Number of Emerged Seedlingsa

(% Reduction)

Seedling Survival

(% Reduction)

Seedling Height (cm)

(% Reduction)

Dry Weight

(g)

(% Reduction)

Day 7

Day 14

Day 21

Control

8.75 ± 1.26b

9.25 ± 0.50

9.25 ± 0.50

9.25 ± 0.50

50.8 ± 5.42

0.32 ± 0.079

391

7.00 ± 0.86

(20%)

8.25 ± 1.26

(11%)

8.50 ± 1.00

(8%)

8.50 ±1.00

(8%)

50.4 ± 2.39

(1%)

0.33 ± 0.019

(-5%)

781

8.50 ± 0.58

(3%)

9.25 ± 0.96

(0%)

9.25 ± 0.96

(0%)

9.25 ± 0.96

(0%)

52.2 ± 1.06

(-3%)

0.34 ± 0.015

(-6%)

1563

8.75 ± 0.96

(0%)

9.25 ± 0.50

(0%)

9.25 ± 0.50

(0%)

9.25 ± 0.50

(0%)

55.8 ± 3.97

(-10%)

0.39 ± 0.059

(-23%)

3125

8.25 ± 0.96

(6%)

9.25 ± 0.50

(0%)

9.25 ± 0.50

(0%)

9.25 ± 0.50

(0%)

52.1 ± 2.68

(-2%)

0.36 ± 0.072

(-14%)

6250

8.25 ± 1.71

(6%)

9.00 ± 2.00

(3%)

9.25 ± 1.50

(0%)

9.25 ± 1.50

(0%)

48.1 ± 4.38

(5%)

0.31 ± 0.043

(4%)

an= 4 replicate pots of 10 seeds each/group.

bMean ± standard deviation. 

None significantly different from control (p = 0.05).

Effects of DBDPEthane on seedling emergence, survival, height, and dry weight in a 21-d seedling emergence test with ryegrass (L. perenne). 

Test Concentration (mg/kg)

Number of Emerged Seedlingsa

(% Reduction)

Seedling Survival

(% Reduction)

Seedling Height (cm)

(% Reduction)

Dry Weight

(g)

(% Reduction)

Day 7

Day 14

Day 21

Control

7.25 ± 0.50b

8.00 ± 0.82

8.00 ± 0.82

8.00 ± 0.82

14.3 ± 1.51

0.017 ± 0.0045

391

6.00 ± 1.41

(17%)

6.25 ± 1.50

(22%)

6.25 ± 1.50

(22%)

6.25 ± 1.50

(22%)

14.7 ± 1.97

(-3%)

0.022 ± 0.0056

(-29%)

781

6.75 ± 3.20

(7%)

7.25 ± 3.20

(9%)

7.75 ± 2.63

(3%)

7.75 ± 2.63

(3%)

14.4 ± 1.67

(0%)

0.024 ± 0.0051

(-37%)

1,563

8.00 ± 0.82

(-10%)

8.25 ± 0.50

(-3%)

8.50 ± 0.58

(-6%)

8.50 ± 0.58

(-6%)

14.6 ± 2.31

(-2%)

0.022 ± 0.0024

(-28%)

3,125

8.50 ± 0.58

(-17%)

9.00 ± 0.82

(-13%)

9.00 ± 0.82

(-13%)

8.75 ± 1.26

(-9%)

14.1 ± 1.78

(2%)

0.021 ± 0.0009

(-23%)

6,250

9.50 ± 0.58

(-31%)

9.50 ± 0.58

(-19%)

9.50 ± 0.58

(-19%)

9.25 ± 0.96

(-16%)

16.0 ± 2.51

(-12%)

0.026 ± 0.0051

(-49%)

an= 4 replicate pots of 10 seeds each/group.

bMean ± standard deviation. 

None significantly different from control (p>0.05).

Effects of decabromodiphenyl ethane (DBDPEthane) on seedling emergence, survival, height, and dry weight in a 21-day seedling emergence test with soybean (G. max)

Test Concentration (mg/kg)

Number of Emerged Seedlingsa

(% Reduction)

Seedling Survival

(% Reduction)

Seedling Height (cm)

(% Reduction)

Dry Weight

(g)

(% Reduction)

Day 7

Day 14

Day 21

Control

6.75 ± 1.50

7.75 ± 0.50

8.00 ± 0.82

8.00 ± 0.82

21.5 ± 1.68

0.34 ± 0.021

391

5.50 ± 2.38b

(19%)

6.25 ± 0.96

(19%)

6.50 ± 1.00

(19%)

6.50 ± 1.00

(19%)

18.6 ± 2.28

(13%)

0.35 ± 0.036

(-3%)

781

5.25 ± 1.50

(22%)

7.25 ± 2.36

(6%)

7.50 ± 2.38

(6%)

7.50 ± 2.38

(6%)

19.0 ± 2.66

(12%)

0.35 ± 0.028

(-3%)

1,563

5.25 ± 1.26

(22%)

6.75 ± 2.06

(13%)

7.00 ± 2.31

(13%)

7.00 ± 2.31

(13%)

18.9 ± 2.20

(12%)

0.38 ± 0.056

(-11%)

3,125

6.75 ± 1.26

(0%)

8.00 ± 2.16

(-3%)

8.25 ± 1.71

(-3%)

8.25 ± 1.71

(-3%)

20.2 ± 1.73

(6%)

0.33 ± 0.046

(3%)

6,250

7.00 ± 2.16

(-4%)

8.00 ± 1.41

(-3%)

8.25 ± 0.96

(-3%)

8.25 ± 0.96

(-3%)

20.7 ± 0.94

(4%)

0.34 ± 0.019

(1%)

an= 4 replicate pots of 10 seeds each/group.

bMean ± standard deviation. 

None significantly different from control (p>0.05).


Effects of decabromodiphenyl ethane (DBDPEthane) on seedling emergence, survival, height, and dry weight in a 21-day seedling emergence test with cucumber (C. sativa).

Test Concentration (mg/kg)

Number of Emerged Seedlingsa

(% Reduction)

Seedling Survival

(% Reduction)

Seedling Height (cm)

(% Reduction)

Dry Weight

(g)

(% Reduction)

Day 7

Day 14

Day 21

Control

7.75 ± 1.26b

8.50 ± 0.58

8.50 ± 0.58

8.50 ± 0.58

9.5 ± 2.28

0.23 ± 0.058

391

8.25 ± 1.71

(-6%)

8.50 ± 1.29

(0%)

8.50 ± 1.29

(0%)

8.50 ± 1.29

(0%)

11.6 ± 2.06

(-22%)

0.28 ± 0.39

(-26%)

781

7.50 ± 1.00

(3%)

8.00 ± 0.82

(6%)

8.25 ± 0.50

(3%)

8.25 ± 0.50

(3%)

8.00 ± 1.43

(16%)

0.19 ± 0.042

(15%)

1563

8.00 ± 0.82

(-3%)

8.25 ± 0.96

(3%)

8.25 ± 0.96

(3%)

8.25 ± 0.96

(3%)

9.8 ± 1.89

(-3%)

0.23 ± 0.059

(-2%)

3125

8.00 ± 0.82

(-3%)

9.00 ± 0.82

(-6%)

9.00 ± 0.82

(-6%)

9.00 ± 0.82

(-6%)

12.2 ± 1.09

(-28%)

0.26 ± 0.045

(-14%)

6250

6.25 ± 0.96

(19%)

7.00 ± 0.82

(18%)

7.25 ± 0.96

(15%)

7.00* ± 0.82

(18%)

8.0 ± 1.78

(16%)

0.22 ± 0.058

(5%)

an= 4 replicate pots of 10 seeds each/group.

bMean ± standard deviation.

*Significantly different from control mean (p<0.05).


 

Effects of decabromodiphenyl ethane (DBDPEthane) on seedling emergence, survival, height, and dry weight in a 21-day seedling emergence test with onion (A. cepa).

Test Concentration (mg/kg)

Number of Emerged Seedlingsa

(% Reduction)

Seedling Survival

(% Reduction)

Seedling Height (cm)

(% Reduction)

Dry Weight

(g)

(% Reduction)

Day 7

Day 14

Day 21

Control

5.00 ± 1.41b

5.25 ± 0.96

5.25 ± 0.96

5.25 ± 0.96

16.2 ± 1.85

0.021 ± 0.0049

391

5.75 ± 0.96

(-15%)

5.75 ± 0.96

(-10%)

5.75 ± 0.96

(-10%)

5.75 ± 0.96

(-10%)

13.0 ± 3.16

(20%)

0.017 ± 0.0053

(20%)

781

5.25 ± 2.36

(-5%)

5.50 ± 2.38

(-5%)

5.50 ± 2.38

(-5%)

5.25 ± 2.36

(0%)

14.2 ± 1.14

(12%)

0.018 ± 0.0050

(15%)

1563

5.50 ± 1.91

(-10%)

5.50 ± 1.91

(-5%)

5.75 ± 2.06

(-10%)

4.50 ± 1.91

(14%)

14.8 ± 1.67

(8%)

0.018 ± 0.0030

(17%)

3125

5.00 ± 1.41

(0%)

6.50 ± 1.29

(-24%)

6.50 ± 1.29

(-24%)

6.50 ± 1.29

(-24%)

12.7* ± 1.18

(22%)

0.015 ± 0.0030

(32%)

6250

6.75 ± 1.50

(-35%)

6.75 ± 1.50

(-29%)

7.00 ± 1.41

(-33%)

6.75 ± 1.50

(-29%)

12.3* ± 1.60

(24%)

0.015 ± 0.0019

(30%)

Note: Inadequate emergence of control seedlings resulted in a repeated test. The results represent the repeated test.

an= 4 replicate pots of 10 seeds each/group.

bMean ± standard deviation. 

*Significantly different from control mean (p<0.05).


 

Effects of decabromodiphenyl ethane (DBDPEthane) on seedling emergence, survival, height, and dry weight in a 21-d seedling emergence test with tomato (L. esculentum).

Test Concentration (mg/kg)

Number of Emerged Seedlingsa

(% Reduction)

Seedling Survival

(% Reduction)

Seedling Height (cm)

(% Reduction)

Dry Weight

(g)

(% Reduction)

Day 7

Day 14

Day 21

Control

9.00 ± 0.82b

9.00 ± 0.82

9.00 ± 0.82

9.00 ± 0.82

15.9 ± 0.88

0.218 ± 0.0214

391

8.00 ± 1.15

(11%)

9.25 ± 0.50

(-3%)

9.25 ± 0.50

(-3%)

9.25 ± 0.50

(-3%)

15.5 ± 3.13

(3%)

0.211 ± 0.0413

(3%)

781

8.25 ± 0.96

(8%)

8.50 ± 1.29

(6%)

8.50 ± 1.29

(6%)

8.50 ± 1.29

(6%)

16.2 ± 0.77

(-2%)

0.251 ± 0.0092

(-15%)

1563

8.00 ± 0.82

(11%)

8.50 ± 1.00

(6%)

8.50 ± 1.00

(6%)

8.50 ± 1.00

(6%)

15.0 ± 1.7c

(6%)

0.222 ± 0.0263c

(-2%)

3125

6.50* ± 2.38

(28%)

7.50 ± 1.29

(17%)

7.50 ± 1.29

(17%)

7.50 ± 1.29

(17%)

14.5 ± 1.06

(9%)

0.264 ± 0.143

(-21%)

6250

3.25* ± 0.96

(64%)

7.50 ± 0.58

(17%)

7.75 ± 0.96

(14%)

7.50 ± 1.00

(17%)

10.0* ± 2.24

(37%)

0.130* ± 0.043

(40%)

Note: Inadequate emergence of control seedlings resulted in a repeated test. The results represent the repeated test.

an= 4 replicate pots of 10 seeds each/group.

bMean ± standard deviation.

cMean, standard deviation and % reduction based on 3 replicates rather than four. One replicate dropped due to inadvertent lack of watering.

*Significantly different from control mean (p<0.05).


LOEC, NOEC, and EC25values from six species of plants exposed to DBDPEthane in soil.

Species

Observed effects (mg/kg)

Calculated EC25(mg/kg)

LOEC

NOEC

Most sensitive endpoint(s)

EC25value

Most sensitive endpoint(s)

Corn

>6,250

6,250

---a

>6,250

---

Cucumber

6,250

3,125

Survival

>6,250

---

Onion

3,125

1,563

Height, dry weight

2,440

Dry weight

Ryegrass

>6,250

6,250

---

>6,250

---

Soybean

>6,250

6,250

---

>6,250

---

Tomato

6,250

3,125

Height, dry weight

4,990

Height

aNot applicable

Seedling Condition Rating System

Rating

Category

Description

0

No Effect

No noticeable effect

10

Slight Effect

Effect barely noticeable

20

Some effect, not apparently detrimental

30

Effect more pronounced, not obviously detrimental

40

Moderate Effect

Effect moderate, plants appear able to recover

50

More lasting effect, recovery somewhat doubtful

60

Lasting effect, recovery doubtful

70

Severe Effect

Heavy injury, loss of individual leaves

80

Plant nearly destroyed, a few surviving leaves

90

Occasional surviving leaves

100

Complete Effect

Death of entire Plant

Rating scale adapted from:

           Frans, Robert E. and Ronald E. Talbert. 1977. Design of Field Experiments and the Measurement and Analysis of Plant Responses. Pages 15-23 in B. Truelove, ed. Research Methods in Weed Science. Southern Weed Science Society, Auburn University, Alabama.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Exposure to DBDPEthane at the highest doses tested (6250 mg/kg dry soil) did not effect corn, ryegrass and soybean seedling emergence and growth.  The NOEC in corn, ryegrass and soybean was 6250 mg/kg. The NOEC in cucumber and tomato was 3125 mg/kg and in onion, 1563 mg/kg. Some effects were noted in onion, cucumber and tomato, which allowed calculation of EC25. The calculated EC25 ranged from 2,440 (onion) to >6,250 mg/kg (corn, cucumber, ryegrass, soybean) based on dry weight (onion) and height (tomato; EC25=4,990 mg/kg).
Executive summary:

The purpose of the 21-d plant study was to determine the effects of the test article on the seedling emergence and growth of six species of plants. The study consisted of a negative control and five treatment groups with four replicate pots of 10 seeds/pot. DBDPEthane was incorporated into the test soil for each treatment group prior to seed planting. The nominal test concentrations were 391, 781, 1,563, 3,125 and 6,250 mg/ kg dry soil. A control group, with no test substance incorporation, was maintained concurrently. Seeds were impartially assigned to growth pots on the day of test initiation, and pots were placed in a randomized block design on a greenhouse table. Observations of emergence and general assessments of seedling condition were made on Days 7, 14, and 21. Plant height and condition scores were made on Day 21, and plants were clipped at soil level and the above-ground portion dried for determination of dry weights. The seedling condition rating system was adapted from Franset al. (1997) with ratings ranging from 0 (no noticeable effect) to 100 (death of entire plant).   The NOECs of DBDPEthane (mg/kg dry soil) in six species of terrestrial plants were 6250 (corn), 3125 (cucumber), 1563 (onion), 6250 (ryegrass), 6250 (soybean), and 3125 (tomato).