N-1-naphthylaniline

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to terrestrial plants: long-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented publication which meets basic scientific principles

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

no

Specific details on test material used for the study:

PHYSICO-CHEMICAL PROPERTIES
- log Pow: 3.3
- volatile

Analytical monitoring:

yes

Vehicle:

yes

Details on preparation and application of test substrate:

- Method of mixing into soil (if used): household mixer
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone or small amount of quartz sand

Species:

Lactuca sativa

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Lettuce
- Plant family: Asteraceae
- Variety: Ravel R2

Test type:

early seedling growth toxicity test

Study type:

laboratory study

Substrate type:

natural soil

Limit test:

no

Total exposure duration:

14 d

Post exposure observation period:

not relevant

Test temperature:

21 ± 4 °C

pH:

7.5 (1 N KCl)

Moisture:

Soil: 25-30% moisture content (80% of water holding capacity)

Details on test conditions:

TEST SYSTEM
- Testing facility: Institute of Environmental Sciences, P.O. Box 6011, 2600 JA Delft, The Netherlands
- Test container (type, material, size): 0.25L plastic trays, covered with glass trays until germination
- Amount of soil: 400 g
- No. of seeds per container: 10 seeds
- No. of plants (retained after thinning): 5
- No. of replicates per treatment group: 2
- No. of replicates per control: 2


SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Soil texture (if natural soil)
- % clay: 12%
- Soil taxonomic classification: agricultural loam
- Organic carbon (%): 1.4% (organic matter content)
- Pretreatment of soil: sieved (4 mm mesh size)


GROWTH CONDITIONS
- Photoperiod: 16 hours day/8 hours night
- Light source: fluorescent tubes
- Light intensity and quality: 1600 lux
- Relative humidity (%): 40-80%
- Wind velocity: none (climatic chamber)
- Watering regime and schedules:
- Water source/type: Evaporation avoided by glass lids, later water replaced by demineralized water
- Interval of applications: daily


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Growth by fresh weight of shoots


VEHICLE CONTROL PERFORMED: yes, in preliminary tests (prior publication)


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3.2

Nominal and measured concentrations:

Nominal: 0, 10, 32 and 100 mg/kg soil
Measured at day 0: 70-150% recovery
Measured at day 14: <50% recovery

Reference substance (positive control):

no

Key result

Species:

Lactuca sativa

Duration:

14 d

Dose descriptor:

EC50

Effect conc.:

> 100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Species:

Lactuca sativa

Duration:

7 d

Dose descriptor:

EC50

Effect conc.:

ca. 100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Results with reference substance (positive control):

not relevant

Reported statistics and error estimates:

Logistic model according to Haanstra et al. 1985; dead plants and ungerminated seeds not taken into account.

Reference 2

Endpoint:

toxicity to terrestrial plants: short-term

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented publication which meets basic scientific principles

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
Please refer also to Read-Across Statement attached in Section 13

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
In this read-across approach data on Naphthalene (CAS 91-20-3, EC 202-049-5) is used to fill data gaps for N-1-naphthylaniline (CAS 90-30-2, EC 201-983-0), in accordance with Regulation No 1907/2006 (REACH), Annex XI. The basis for this read-across approach is the “Read-Across Assessment Framework” (RAAF) (ECHA 2017). The read-across hypothesis for the analogue approach is that N-1-naphthylaniline and Naphthalene exhibit a comparable ecotoxicological hazardous potential as a consequence of structural similarity. The target substance N-1-naphthylamine is a member of Naphthalenes, with the Naphthalene structure being part of the molecule, representing a relevant structure in terms of their ecotoxicological effects. The differences in the molecular structure and the associated differences in physical properties explain the slight differences in the potency of the substance. Nonetheless, from a regulatory point of view, the degree of danger of both substances is comparable.
According to the RAAF this approach is covered by scenario 2, based on “different compounds with qualitatively similar properties”.
“This scenario covers the analogue approach for which the hypothesis is based on different compounds with the same type of effect(s). For the REACH information requirement under consideration, the effects obtained in a study conducted with one source substance are used to predict the effects that would be observed in a study with the target substance if it were to be conducted. The same type of effect(s) or absence of effect is predicted. The predicted strength of the effects may be similar or based on a worst-case approach.”

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Target chemical:
N-1-naphthylaniline, CAS number: 90-30-2, EC number: 201-983-0, Molecular formula: C16H13N, Molecular weight: 219.28 g/mol

Source chemical:
Naphthalene, CAS: 91-20-3, EC number: 202-049-5, Molecular formula: C10H8, Molecular weight: 128.17 g/mol

3. ANALOGUE APPROACH JUSTIFICATION
QSAR profiling reveal no significant differences between the source Naphthalene and the target substance N-1-naphthylaniline, the available data show a comparability of the relevant physico-chemical parameters and a similarity in the ecotoxicological profile, what justifies this read across. Thus, the available studies for the source substances Naphthalene are used to fill data gaps N-1-naphthylaniline for the following ecotoxicological endpoints: Toxicity to sediment organisms, Toxicity to soil microorganisms except arthropods, Toxicity to terrestrial arthropods, Toxicity to terrestrial plants and Toxicity to birds (for further details please refer to attached Read-Across Statement in Section 13).

4. DATA MATRIX
(please refer to attached Read-Across Statement in Section 13)

Reason / purpose for cross-reference:

read-across source

Key result

Species:

other: Trifolium repens

Duration:

15 d

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Remarks:

(dry weight)

Species:

other: Trifolium repens

Duration:

15 d

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: DNA content variations 2c nuclei

Species:

other: Trifolium repens (roots)

Duration:

15 d

Dose descriptor:

other: 17% DNA polymorphisms

Effect conc.:

50 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: random DNA change

Species:

other: Trifolium repens (roots)

Duration:

15 d

Dose descriptor:

other: 23% DNA polymorphisms

Effect conc.:

100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: random DNA change

Details on results:

- Other effects: Naphthalene did not affect white clover (Trifolium repens) development and ploidy, but showed DNA sequence changes (fragmentation, point and chromosomal mutations) in roots and shoots, slightly more in roots.

Reported statistics and error estimates:

Plant growth and flow cytometry: Statgraphics plus version 4.0, ANOVA and Dunnett's test (normality and homogeneity of variance satisfied), otherwise log transformation and Kruskal-Wallis

AFLP: Comparison of proportaion analysis

Reference 3

Endpoint:

toxicity to terrestrial plants: short-term

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented publication which meets basic scientific principles

Qualifier:

no guideline followed

Principles of method if other than guideline:

phytotoxicity test in nutrient solution

GLP compliance:

no

Specific details on test material used for the study:

PHYSICO-CHEMICAL PROPERTIES
- log Pow: 3.3
- volatile

Analytical monitoring:

yes

Vehicle:

yes

Details on preparation and application of test substrate:

- Chemical name of vehicle (organic solvent, emulsifier or dispersant): tributylalcohol
- semistatic: nutrient solution renewed 3 times per week

Species:

Lactuca sativa

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Lettuce
- Plant family: Asteraceae
- Variety: Ravel R2

Test type:

early seedling growth toxicity test

Study type:

laboratory study

Substrate type:

other: nutrient solution

Limit test:

no

Total exposure duration:

16 d

Test temperature:

21 ± 4 °C

pH:

7.5 (1 N KCl)

Details on test conditions:

TEST SYSTEM
- Testing facility: Institute of Environmental Sciences, P.O. Box 6011, 2600 JA Delft, The Netherlands
- Test container (type, material, size): 0.25L plastic trays and water saturated perlite, covered with glass trays until germination
- Test container (after seedlings >3 cm transferred): 1L pots filled with nutrient solution
- No. of seeds per container: 10 seeds
- No. of plants (retained after thinning in 1 L pots): 5
- No. of replicates per treatment group: 2
- No. of replicates per control: 2



GROWTH CONDITIONS
- Photoperiod: 16 hours day/8 hours night
- Light source: fluorescent tubes
- Light intensity and quality: 1600 lux
- Relative humidity (%): 40-80%
- Wind velocity: none (climatic chamber)
- Watering regime and schedules:
- Water source/type: Evaporation avoided by glass lids, later water replaced by demineralized water
- Interval of applications: daily


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Growth by fresh weight of shoots


VEHICLE CONTROL PERFORMED: yes, in preliminary tests (prior publication)


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3.2

Nominal and measured concentrations:

Nominal: 0 and unknown concentrations in mg/L
Measured at day 0: 70-150% recovery
Measured at day 16: <50% recovery

Reference substance (positive control):

no

Key result

Species:

Lactuca sativa

Duration:

16 d

Dose descriptor:

EC50

Effect conc.:

13 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Remarks on result:

other: 4.8-34

Reported statistics and error estimates:

Logistic model according to Haanstra et al. 1985; dead plants and ungerminated seeds not taken into account.

In contrast to the soil experiments, the nutrient solution results showed a higher sensitivity (probably due to renewal of test substance with nutrient solution test), also no adsorption processes were observed in nutrient solution. The relationship between toxicity of all miscellaneous substances tested in the study in soil solution and nutrient solution gave the regression: y=1.3x + 0.27 (r=0.87, n=19)

Additional information

No data are available for the toxicity of N-phenyl-1-naphthylamine to terrestrial organisms. Therefore, information from a supporting, structurally analogue compound (naphthalene) was taken into account.

In the key study, the effect of naphthalene (purity approx. 95%) on Lactuca sativa early seedling growth was tested in a soil medium according to OECD guideline 208 (Hulzebos 1993). Nominal concentrations of 0, 10, 32 and 100 mg/L were tested, with acetone or quartz sand as solvent (several test substances in study, not further specified). The effect on seedling growth was determined as EC50(14d) > 100 mg/kg soil. Less than 50% of the test substance was recovered at test end using analytical methods.

More sensitive results were achieved in the same study using a nutrient solution as medium (semi-static). The effect of naphthalene (purity approx. 95%) on seedling growth was determined as EC50(16d) of 13 mg/L. Another supporting study investigating growth and genotoxic effects of naphthalene (purity unknown) with Trifolium repens determined an EC0(15d) > 100 mg/kg soil based on growth, an EC0(15d) >100 mg/kg soil based on 2c nuclei DNA content variations, and 17% DNA polymorphism at 50 mg/kg soil and 23% DNA polymorphism at 100 mg/kg soil, respectively.