Registration Dossier

Administrative data

Endpoint:
bioaccumulation in aquatic species: fish
Type of information:
(Q)SAR
Adequacy of study:
key study
Study period:
depending on ECHA feedback; expected 2011-2012
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:
1. SOFTWARE: BCFBAF v3.01 (Sep 2012) in EPI Suite v4.11, U.S. Environmental Protection Agency

2. MODEL (incl. version number): BCFBAF v3.01 regression method

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL: CASRN 27247-96-7, SMILES: O(N(=O)=O)CC(CCCC)CC; also input experimental log Kow of 5.24

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
[Explain how the model fulfils the OECD principles for (Q)SAR model validation. Consider attaching the QMRF or providing a link]

- Defined endpoint: bioconcentration factor (BCF) in fish

- Unambiguous algorithm:

Log BCF  =  0.6598 Log Kow  -  0.333  + Σ correction factors ( (n = 396, r2 = 0.792, Q2 = 0.78, std dev = 0.511, avg dev = 0.395)

- Defined domain of applicability:

MW 68.08 - 991.80 (training set of 527 chemicals) -- target substance has a MW of 175.23
log Kow: -1.37 to 11.26 -- target substance has log Kow of 5.24

- Appropriate measures of goodness-of-fit and robustness and predictivity:

Accuracy of training set: r2 = 0.833; s.d= 0.502; a.d. 0.382 (n = 527)
Accuracy of validation set: r2 = 0.82; s.d. = 0.59; a.d. = 0.46 (n = 158)

- Mechanistic interpretation:

passive diffusion (partitioning) into the lipid phase (process by which lipophilic organic chemicals are bioaccumulated in fish through the respiratory organs)


5. APPLICABILITY DOMAIN
[Explain how the substance falls within the applicability domain of the model]
- Descriptor domain:target substance is within the log Kow and MW parametric domain
- Structural and mechanistic domains:
- Similarity with analogues in the training set:The training set contains a diverse set of chemicals, some of which are structurally similar to the target, e.g. 2-ethylhexyl vinyl ether
- Other considerations (as appropriate): The BCFBAF model for non-ionic compounds is meant for use for a wide variety of chemicals.

6. ADEQUACY OF THE RESULT
[Explain how the prediction fits the purpose of classification and labelling and/or risk assessment]

Data source

Reference
Title:
BCFBAF v3.01
Year:
2012
Bibliographic source:
Meylan et al. 1997.  "Improved Method for Estimating Bioconcentration Factor (BCF) from Octanol-Water Partition Coefficient", SRC TR-97-006 (2nd Update), July 1997; prepared for U.S. EPA; prepared by: ; SRC, North Syracuse, NY 13212.  

Materials and methods

Test guidelineopen allclose all
Guideline:
OECD Guideline 305 (Bioaccumulation in Fish: Aqueous and Dietary Exposure) -I: Aqueous Exposure Bioconcentration Fish Test
Version / remarks:
experimental data in the training set is gathered mostly by OECD 305 type tests
Guideline:
other: ECHA Practical guide: how to use and report (Q)SARs, v3.1 - July 2016

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
SMILES: O(N(=O)=O)CC(CCCC)CC

Results and discussion

Bioaccumulation factor
Key result
Type:
BCF
Value:
1 332 L/kg

Any other information on results incl. tables

BCFBAF model estimated the BCF of 2 -ethylhexyl nitrate to be 1332 L/kg by the regression method.

Applicant's summary and conclusion