4-(4-isopropoxyphenylsulfonyl)phenol

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to terrestrial plants: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2004-03-30 to 2004-09-06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

The soil was delivered and analysed by the LUFA Speyer.
Following parameters were analysed:
Lufa 2.3 (sandy loam; USDA)
all particles smaller than 0.2 cm
1.02 ± 0.17 % organic carbon
pH 6.3 ± 0.4

Species:

Avena sativa

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

Monocotyledonae
Poaceae
Avena sativa
Oat

Species:

Brassica napus

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

Dicotyledonae
Brassicaceae
Brassica napus
Oilseed Rape

Species:

Glycine max (G. soja)

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

Dicotyledonae
Fabaceae
Glycine max
Soybean

Test type:

seedling emergence and seedling growth test

Study type:

laboratory study

Substrate type:

natural soil

Limit test:

no

Total exposure duration:

21 d

Test temperature:

Temperature [°C]: day / night
Mean: 24.3 / 17.9
Minimum: 23.1 / 17.1
Maximum: 25.5 / 18.6

pH:

6.3 ± 0.4

Moisture:

Humidity [% R.H.]: day / night:
Mean: 52.9 / 61.4
Minimum: 34.9 / 46.3
Maximum: 65.2 / 75.4

Details on test conditions:

Test Environment: The test was performed in a growth chamber under controlled conditions.
Light Regime: 16 h light : 8 h dark;
Light intensity (day):
Mean: 9498 Lux;
Minimum: 5360 Lux;
Maximum: 18200 Lux;
Irrigation: Bottom watering (through saucers) was done where necessary after a daily spot check. Water was given in order to assure optimal water supply of the plants.
Moisture Check: A spot check on soil moisture was carried out daily.
Fertilizer: Flory 9 (Euflor) 1 g/L with Sequestren (Ciba-Geigy) 0.05 g/L was given after development of the first true leaves. Fertilizer was given one to three times a week depending on the development of the plants.

Nominal and measured concentrations:

Nominal concentrations: mg D-8/kg soil dry weight - 1000; 400; 160; 64; 25.6, 10.24
No measured concentrations.

Reference substance (positive control):

no

Species:

Avena sativa

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

697.15 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Key result

Species:

Brassica napus

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

65.39 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Species:

Glycine max (G. soja)

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

302.65 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight.

Species:

Avena sativa

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 25.6 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Key result

Species:

Brassica napus

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 10.24 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Species:

Glycine max (G. soja)

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 25.6 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Details on results:

Avena sativa:
Fresh Weight:
Fresh weight was statistically significantly reduced at all tested concentrations (12 to 53 %). The growth stages were not affected. Based on fresh weight the effective concentrations were determined.
Germination:
The germination rate was 100 % in the control. The germination rate ranged between 90 and 98 % in the treatment groups without showing any treatment related tendency or statistical significance compared to the controls.
Mortality:
Mortality was not observed.
Phytotoxicity, 21 DAA:
Phytotoxic effects were growth reduction. Phytotoxicity was observed at 160 mg D-8/kg soil dry weight and above up to the highest concentration (2 to 3 %).
DAA = days after application

Brassica napus:
Fresh Weight:
Fresh weight was statistically significantly reduced at all tested rates (10 to 82 %). The growth stages were slightly reduced at 160 mg test item/kg soil and above. Based on fresh weight the effective concentrations were determined.
Germination:
The germination rate was 95 % in control. The germination rate ranged between 90 and 100 % in the treatment groups without showing any treatment related tendency or statistical significance compared to the control.
Mortality:
Mortality was observed at 10.24 mg D-8/kg soil dry weight (3 %). This was not statistically significant and treatment related. Mortality was observed between day 7 and 14 when germination was observed but from the next week the seedling could not be counted any more.
Phytotoxicity, 21 DAA:
Phytotoxic effects, chlorosis and growth depression, were observed at 64 mg D-8/kg soil dry weight and above up to the highest concentration (2 to 23 %).
DAA = days after application

Glycine max:
Fresh Weight:
Fresh weight was significantly reduced compared to the control at all tested rates (25 to 59%). The growth stages were slightly reduced at 160 mg D-8/kg soil dry weight and above. Based on fresh weight the effective concentrations were determined.
Germination:
The germination rate was 100 % in the control. The germination rate ranged between 98 and 100 % in the treatment groups without showing any treatment related tendency or statistical significance compared to the control.
Mortality:
Mortality was not observed.
Phytotoxicity, 21 DAA:
Phytotoxic effects were chlorosis and growth depression. Phytotoxicity was observed at 64 mg D-8/kg soil dry weight and above up to the highest concentration (1 to 11 %).
DAA = days after application

Reported statistics and error estimates:

Statistical Analysis:
Fresh weight data were tested for normality by using Kolmogoroff-Smirnov-Test. Homogeneity was tested with Cochran-Test.
If the data were normally distributed, homogeneous and monotonous Dunnett-Test was used. If the data were normally distributed, homogeneous and not monotonous Williams-Test was used.
In order to determine the EC25 and EC50 values, a regression analysis (Probit-analysis) was performed.
For the germination and mortality data Fischer Exact Test was used.
The computer programs used to perform the statistical analyses were ToxRat SPiRiT Solutions (2001-2003), Version 2.07 and SYSTAT Version 9.
The significance level for all tests was α = 0.05.

The most sensitive species was Brassica napus with an EC50 of 65.39 mg D-8/kg soil dry weight followed by Glycine max and Avena sativa with EC50 values of 302.65 and 697.15 mg D-8/kg soil dry weight, respectively. The EC50 values were calculated based on fresh weight. D-8 caused no effect on the germination or mortality of the tested species in this study. As phytotoxic symptoms chlorosis and growth reduction were observed at 64 mg a.i./kg soil dry weight (Brassica napus) and at 160 a.i./kg soil dry weight (Glycine max and Avena sativa) up to the highest concentration, each.

Validity criteria fulfilled:

yes

Remarks:

In order for the test to be valid, the germination rate of the control seeds had to be minimum 65 %, the control seedlings should have exhibited normal growth throughout the test.

Conclusions:

Based on the fresh weight, the most sensitive species was Brassica napus with an EC50 of 65.39 mg D-8/kg soil dry weight followed by Glycine max and Avena sativa with EC50 values of 302.65 and 697.15 mg D-8/kg soil dry weight, respectively. The NOEC for Brassica napus was estimated to be <10.24 mg/kg dw soil. Whereas for the other specied it was <25.6 mg/kg dw soil.

Executive summary:

D-8 was tested for effects on the seedling emergence and seedling growth of 3 species out of 3 different plant families in accordance with OECD 208. As substrate soil LUFA Speyer was used. The seedling and emergence of three plant species – Avena sativa, Brassica napus and Glycine max, was observed during the exposure period of 21 days. At the end of the test the most sensitive specie was determined to be Brassica napus with an EC50 of 65.39 mg D-8/kg soil dry weight followed by Glycine max and Avena sativa with EC50 values of 302.65 and 697.15 mg D-8/kg soil dry weight, respectively. The EC50 values were calculated based on fresh weight. D-8 caused no effect on the germination or mortality of the tested species in this study. As phytotoxic symptoms chlorosis and growth reduction were observed at 64 mg a.i./kg soil dry weight (Brassica napus) and at 160 a.i./kg soil dry weight (Glycine max and Avena sativa) up to the highest concentration, each. The NOEC for Brassica napus was estimated to be <10.24 mg/kg dw soil. Whereas for the other specied it was <25.6 mg/kg dw soil.

Reference 2

Endpoint:

toxicity to terrestrial plants: short-term

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

from 2003-10-27 to 2004-09-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

The soil was delivered and analysed by the LUFA Speyer.
Following parameters were analysed:
Lufa 2.3 (sandy loam; USDA)
all particles smaller than 0.2 cm
1.02 ± 0.17 % organic carbon
pH 6.3 ± 0.4

Species:

Avena sativa

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

Monocotyledonae
Poaceae
Avena sativa
Oat

Species:

Brassica napus

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

Dicotyledonae
Brassicaceae
Brassica napus
Oilseed Rape

Species:

Glycine max (G. soja)

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

Dicotyledonae
Fabaceae
Glycine max
Soybean

Test type:

seedling emergence and seedling growth test

Study type:

laboratory study

Substrate type:

natural soil

Limit test:

yes

Total exposure duration:

21 d

Test temperature:

Temperature [°C]: day / night:
Mean: 24.7 / 17.8
Minimum: 23.0 / 16.9
Maximum: 27.6 / 18.7

pH:

6.3 ± 0.4

Moisture:

Humidity [% R.H.]: day / night:
Mean: 54.8 / 64.8
Minimum: 44.2 / 50.4
Maximum: 68.0 / 77.4

Details on test conditions:

Test Environment: The test was performed in a growth chamber under controlled conditions.
Light Regime: 16 h light : 8 h dark
Light intensity (day):
Mean: 9473 Lux
Minimum: 5120 Lux
Maximum: 18890 Lux
Irrigation: Bottom watering (through saucers) was done where necessary after a daily spot check. Water was given in order to assure optimal water supply of the plants.
Moisture Check: A spot check on soil moisture was carried out daily.
Fertilizer: Flory 9 (Euflor) 1 g/L with Sequestren (Ciba-Geigy) 0.05 g/L was given after development of the first true leaves. Fertilizer was given one to three times a week after the first true leaves were developed.

Nominal and measured concentrations:

Nominal: 1000 mg test item/kg soil dry weight
No measured concentrations.

Reference substance (positive control):

no

Key result

Species:

Avena sativa

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Species:

Avena sativa

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Key result

Species:

Brassica napus

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Species:

Brassica napus

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Key result

Species:

Glycine max (G. soja)

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Species:

Glycine max (G. soja)

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: fresh weight

Details on results:

Brassica napus:
Fresh Weight:
Fresh weight was statistically significantly reduced at 1000 mg test item/kg soil (83.53 %). The growth stages were slightly reduced at 1000 mg test item/kg soil. Based on fresh weight the effective concentrations were determined.
Germination:
The germination rate was 100 % in control and 95 % in the treatment group. This was not statistically significant compared to the control.
Mortality:
Mortality was not observed.
Phytotoxicity, 21 DAA:
Phytotoxic effects, chlorosis and growth depression, were observed at 1000 mg D-8/kg soil dry weight (30 %).
DAA = days after application

Avena sativa:
Fresh Weight:
Fresh weight was statistically significantly reduced at 1000 mg test item/kg soil (59.92 %). The growth stages were not affected. Based on fresh weight the effective concentrations were determined.
Germination:
The germination rate was 88 % in control and 90 % in the treatment group. This was not statistically significant compared to the control.
Mortality:
Mortality was not observed.
Phytotoxicity, 21 DAA:
Phytotoxic effects were chlorosis and growth depression. Phytotoxicity was observed at 1000 mg D-8/kg soil dry weight (5 %).
DAA = days after application

Glycine max:
Fresh Weight:
Fresh weight was statistically significantly reduced at 1000 mg test item/kg soil (32.59 %). The growth stages were not affected. Based on fresh weight the effective concentrations were determined.
Germination:
The germination rate was 85 % in control and 90 % in the treatment group. This was not statistically significant compared to the control.
Mortality:
Mortality was not observed.
Phytotoxicity, 21 DAA:
Phytotoxic effects were growth reduction. Slight phytotoxicity was observed at 1000 mg D-8/kg soil dry weight.
DAA = days after application

Reported statistics and error estimates:

Statistical Analysis:
For normally distributed and homogenous data pairwise comparison was done with Student t-Test for homogenous variances.
For the germination data Fischer Exact Test was used.
The significance level for all tests was alpha = 0.05.
The computer programs used to perform the statistical analyses were ToxRat SPiRiT Solutions (2001-2003), Version 2.07 and SYSTAT Version 9.

The most sensitive species was Brassica napus followed by Avena sativa and Glycine max.

Germination rate and mortality were not affected by D-8.

Phytotoxic symptoms like chlorosis and growth depression were observed for Brassica napus and Avena sativa.

Glycine max showed growth depression, only.

Validity criteria fulfilled:

yes

Remarks:

The study is valid because the plants showed normal growth throughout the test, the germination in the control pots was above 65 % and survival of control plants was > 90 %.

Conclusions:

The most sensitive specie was determined to be Brassica napus followed by Avena sativa and Glycine max with reductions in fresh weight of 84, 60 and 33 %, respectively.

Executive summary:

D-8 was tested for effects on the seedling emergence and seedling growth of 3 species out of 3 different plant families in accordance with OECD 208. As substrate soil LUFA Speyer was used. The seedling and emergence of three plant species – Avena sativa, Brassica napus and Glycine max, was observed during the exposure period of 21 days in a limit test with a test concentration of 1000 mg/kg soil dry weight. The most sensitive specie was determined to be Brassica napus followed by Avena sativa and Glycine max with reductions in fresh weight of 84, 60 and 33 %, respectively. All reductions were statistically significant compared to the control. Germination rate and mortality were not affected by D-8. Phytotoxic symptoms observed for Brassica napus were chlorosis and growth depression. Avena sativa and Glycine max showed growth depression, only.

Description of key information

In a seedling emergence test, based on the fresh weight, the most sensitive species was Brassica napus with an EC50 of 65.39 mg D-8/kg soil dry weight followed by Glycine max and Avena sativa with EC50 values of 302.65 and 697.15 mg D-8/kg soil dry weight, respectively. The NOEC for Brassica napus was estimated to be <10.24 mg/kg dw soil. Whereas for the other specied it was <25.6 mg/kg dw soil.

Key value for chemical safety assessment

Short-term EC50 or LC50 for terrestrial plants:

65.39 mg/kg soil dw

Long-term EC10, LC10 or NOEC for terrestrial plants:

10.24 mg/kg soil dw

Additional information

Key study - OECD 208

D-8 was tested for effects on the seedling emergence and seedling growth of 3 species out of 3 different plant families in accordance with OECD 208. As substrate soil LUFA Speyer was used. The seedling and emergence of three plant species – Avena sativa, Brassica napus and Glycine max, was observed during the exposure period of 21 days. At the end of the test the most sensitive specie was determined to be Brassica napus with an EC50 of 65.39 mg D-8/kg soil dry weight followed by Glycine max and Avena sativa with EC50 values of 302.65 and 697.15 mg D-8/kg soil dry weight, respectively. The EC50 values were calculated based on fresh weight. D-8 caused no effect on the germination or mortality of the tested species in this study. As phytotoxic symptoms chlorosis and growth reduction were observed at 64 mg a.i./kg soil dry weight (Brassica napus) and at 160 a.i./kg soil dry weight (Glycine max and Avena sativa) up to the highest concentration, each. The NOEC for Brassica napus was estimated to be <10.24 mg/kg dw soil. Whereas for the other specied it was <25.6 mg/kg dw soil.

Supporting study - OECD 208

D-8 was tested for effects on the seedling emergence and seedling growth of 3 species out of 3 different plant families in accordance with OECD 208. As substrate soil LUFA Speyer was used. The seedling and emergence of three plant species – Avena sativa, Brassica napus and Glycine max, was observed during the exposure period of 21 days in a limit test with a test concentration of 1000 mg/kg soil dry weight. The most sensitive specie was determined to be Brassica napus followed by Avena sativa and Glycine max with reductions in fresh weight of 84, 60 and 33 %, respectively. All reductions were statistically significant compared to the control. Germination rate and mortality were not affected by D-8. Phytotoxic symptoms observed for Brassica napus were chlorosis and growth depression. Avena sativa and Glycine max showed growth depression, only.