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Ecotoxicological information

Toxicity to terrestrial plants

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Administrative data

Endpoint:
toxicity to terrestrial plants: long-term
Type of information:
(Q)SAR
Adequacy of study:
key study
Study period:
2017
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
Justification for type of information:
The target lipid model (TLM) is a framework that relates toxicity to the physicochemical properties of a nonpolar organic constituent. The TLM, and HC5, have been applied to soils and sediment using equilibrium partitioning (EqP) model. This framework utilizes organic carbon partition coefficients (Koc) to convert aquatic based effect levels (CW) to bulk soil- and sediment-based effect levels. The combined TLM-EqP framework was validated previously for soil and sediment acute and chronic toxicity endpoints. The registered substance is within the scope of the TLM and EqP frameworks.

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
Refinement and validation of TLM-derived HC5 values. Independent review.
Author:
McGrath JA, Di Toro DM, Fanelli CJ
Year:
2015
Bibliographic source:
HDR, Mahwah, NJ
Reference Type:
publication
Title:
Extension and validation of the target lipid model for deriving predicted no-effect concentrations for soils and sediments
Author:
Redman AD, Parkerton TF, Paumen ML, McGrath JA, den Haan K, DiToro DM
Year:
2014
Bibliographic source:
Environmental Toxicology and Chemistry, 33: 12, pp. 2679-2687.

Materials and methods

Test guideline
Qualifier:
no guideline required
Principles of method if other than guideline:
The target lipid model (McGrath et el., 2015) and equilibrium partitioning model (Redman et al., 2014) as described in the cited references were used to determine soil effect levels of the registered substance. A detailed explanation of the calculation method is provided in the 'Attached justification'.
For detailed model description and justification of QSAR prediction: see fields 'Justification for type of information' and 'Attached justification'.
GLP compliance:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
Benzene
EC Number:
200-753-7
EC Name:
Benzene
Cas Number:
71-43-2
Molecular formula:
C6H6
IUPAC Name:
benzene
Test material form:
not specified
Details on test material:
Common name: Benzene
No other data provided
Specific details on test material used for the study:
NA

Test organisms

open allclose all
Species:
Avena sativa
Plant group:
Monocotyledonae (monocots)
Species:
Brassica rapa
Plant group:
Dicotyledonae (dicots)

Results and discussion

Effect concentrationsopen allclose all
Species:
Avena sativa
Duration:
14 d
Dose descriptor:
LC50
Effect conc.:
133.825 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
seedling emergence
Species:
Avena sativa
Duration:
21 d
Dose descriptor:
EC10
Effect conc.:
25.637 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth
Species:
Brassica rapa
Duration:
14 d
Dose descriptor:
LC50
Effect conc.:
86.405 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
seedling emergence
Species:
Brassica rapa
Duration:
21 d
Dose descriptor:
EC10
Effect conc.:
16.553 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The TLM-EqP predicted effect values for Benzene were 86.405 and 16.553 mg/kg soil dw for short-term (14-day LC50) and long-term effects (21-day EC10) to Brassica rapa, respectively. The TLM-EqP predicted effect values for Benzene were 133.825 and 25.637 mg/kg soil dw for short-term (14-day LC50) and long-term effects (21-day EC10) to Avena sativa, respectively.
Executive summary:

The registered substance is highly volatile which complicates environmental testing. Therefore, a modeling framework is needed to account for the bioavailability of the substance to perform read-across and data gap filling. The TLM-EqP modeling has been validated as a suitable method for predicting effect values in terrestrial plants. The TLM-EqP predicted effect values for Benzene were 86.405 and 16.553 mg/kg soil dw for short-term (14-day LC50) and long-term effects (21-day EC10) to Brassica rapa, respectively. The TLM-EqP predicted effect values for Benzene were 133.825 and 25.637 mg/kg soil dw for short-term (14-day LC50) and long-term effects (21-day EC10) to Avena sativa, respectively.