Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 275-702-5
CAS number: 71617-10-2
The ECHA guidance R.7c proposes a scheme for the thought processes that
must be considered with regard to the BCF for substances produced or
imported at 100 t/y or above (building on the concepts discussed by de
Wolf et al. 2007).
STEP 1: Characterisation of the substance
This includes the verification of the chemical structure, which is well
known for isopentyl p-methoxycinnamate. The relevant physico-chemical
properties should be gathered, which was done for isopentyl
p-methoxycinnamate. The substance has a vapour pressure of 0.0066 Pa at
25 °C, a water solubility of 0.8 mg/L at 20 °C, a log KOW of 4.78 and an
estimated adsorption coefficient of log KOC = 3.56. If the log KOW is
greater 3, a preliminary BCF estimate should be done with linear models
(e.g. Meylan et al. 1999) for substances with log KOW < 6, which is the
case for isopentyl p-methoxycinnamate.
STEP 2: Identification of possible analogues
A search for experimental data on chemical analogues should be
performed. This may lead to the conclusion that the substance belongs to
a group of substances that are known to have potential to bioaccumulate.
It may also help to clarify if log KOW is a good predictor for
A structural similar substance with experimental BCF data was found:
2-ethylhexyl 4-methoxycinnamate (BCF = 433 whole body w.w.)
STEP 3A: Evaluation of existing in vivo data
It should be evaluated if in vivo data on the substance, including data
on invertebrates, are available that can be used for the
characterisation of bioaccumulation potential. Such information is
available for isopentyl p-methoxycinnamate (see step 2).
STEP 3B: Evaluation of non-testing data
The use of log KOW based QSARs normally is recommended if KOW is a good
predictor of bioconcentration. A justification for use of a particular
model should be provided. In general, a cautious conclusion on the
predicted BCF values should be drawn and the upper range of predicted
values of the most relevant and reliable QSAR models should be used. In
this study, the BCF was predicted with two models being proposed in the
ECHA guidance R.7c. First, the BCF was estimated with the BCFBAF program
included in the EPI Suite program of the US EPA, which applies the
fragment-based approach of Meylan et al. 1999. The model gave a log BCF
of 2.82. Second, the BCF was calculated with the CAESAR BCF model
proposed by Zhao et al. 2008 giving a log BCF value of 1.45. Both QSAR
models give BCFs indicating that isopentyl p-methoxycinnamate may have a
certain potential for bioaccumulation in aquatic organisms.
Nevertheless, BCFs predicted with the models are below the cut-off
criterion of 2000 L/kg used for classification of a substance as
bioaccumulative. Thus, the B criterion is not fulfilled for isopentyl
STEP 3C: Evaluation of in vitro data
If in vitro data are available these may be used to estimate a BCF
value. Such data are not available.
STEP 4A: Weight of evidence assessment
The available and reliable information should be summarised and it
should be examined if any single piece of information merits a
conclusion on BCF or if further testing may be required. If no
experimental fish BCF data are available, the BCF should be estimated
from the KOW and it should be checked if the estimated BCF predicted
from the KOW may be reduced by applying a set of strong and weak
indicators given in ECHA guidance R.7c. Furthermore, data from
invertebrate studies may be taken into account.
The screening criterion of log KOW > 3 is fulfilled showing that the
substance may have the potential to bioaccumulate to a significant
extent. Two different validated QSAR models were then applied to get
further information on the substance’s BCF. The model from Meylan et al.
(1999) gives a log BCF of 2.82 and the model of Zhao et al. (2008) gives
a log BCF of 1.45. Both computed BCFs indicate that allyl
3-cyclohexylpropionate has a certain potential to bioaccumulate in
aquatic organisms. Nevertheless, both QSAR models return BCFs of less
than 2000 L/kg. A BCF above this cut-off value triggers classification
of a substance as bioaccumulative. Consequently, the substance should
not be considered as bio-accumulative. Further testing on the BCF of the
substance in aquatic organisms is deemed not necessary.
The bioconcentration factor of the substance was estimated with the
BCFBAF model included in the Episuite tool (as of September 2010). This
program uses a fragment-based approach that is based on a set of 610
non-ionic substances. The experimental log Kow value of 4.78 was used in
the calculation. The estimated BCF was 662 L/kg. Additionally, the BCF
of the substance was calculated using the CAESAR QSAR hybrid model (Zhao
et al. 2008). The estimated BCF with the second model was 28 L/kg. Both
modelled values are below the cut-off value of 2000 L/kg triggering
classification of substances as bioaccumulative. The B criterion is not
fulfilled and the substance is considered as not bioaccumulative.
The substance is considered as not bioaccumulative. It is proposed to use a BCF of 662 L/kg in the chemical safety assessment as this was the maximum predicted BCF.
The bioaccumulation factor (BCF) for fish was calculated using
QSAR based software approaches. The QSAR model used by Episuite (Epiweb
4.0, BCFBAF program) is based on correlations between BCF and chemical
hydrophobicity (as modelled by log KOW).
The Caesar BCF model is based on a dataset of 473 compounds with
experimentally determined BCF values. The final model is a Neural
Network based on 8 molecular descriptors.
, a log KOW of 4.78 (see section 4.7 of the IUCLID
dataset) was determined experimentally. Using this value, Episuite
[BCFBAF (v3.00)] calculated a BCF value of 662 L/kg body weight (BCFBAF
2010). Using the Caesar QSAR model software a BCF value 28 L/kg body
weight was obtained (Caesar 2010).
Both values are below the cut-off value of 2000 L/kg triggering
classification of substances as bioaccumulative. It is concluded that
the B criterion is not met and the substance is not considered as
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again