The downloadable materials included on this website are provided to interested parties at no cost; however, to download any material you need to first request a password by completing a form with your name, e-mail address and affiliation. The registration information provides us with contact information so that we can send notifications for model updates. The models are updated occasionally to address potential errors and “bugs in the code” and to reflect scientific advancements.

The most recent versions of the models and databases are most relevant since they include updates and possibly corrections to previous versions. Users are strongly encouraged to read the associated papers listed with the models and the “help” and “about” information accompanying the models (when included) before using them. Excel spreadsheets are expected to work using Microsoft Office or other similar programs (Note: Visual Basic for Applications support is often required).

For more information about these models, tools and databases please contact Jon Arnot.

The Bioaccumulation Assessment Tool (BAT)

The Bioaccumulation Assessment Tool (BAT) facilitates the systematic and transparent integration of information in a consistent framework to inform bioaccumulation assessment decision-making.

The BAT is a user-friendly spreadsheet-based tool to guide the collection, generation, evaluation, and integration of various lines of evidence (LOE) to aid bioaccumulation assessment decision-making for aquatic and terrestrial organisms.  The BAT provides a consistent Quantitative Weight of Evidence (QWOE) approach that includes critical evaluations of data confidence. The BAT can provide guidance for integrated testing strategies should further information be necessary for decision-making.


+ Read more about the Bioaccumalation Assessment Tool (BAT)
Chemicals are being assessed for bioaccumulation (B) potential using various LOEs, methods, metrics and classification criteria.  In vivo laboratory-based lines of evidence include the bioconcentration factor (BCF) and biomagnification factor (BMF).  In vitro biotransformation rate data (S9, hepatocytes) can also be applied for “B” assessment using in vitro-in vivo extrapolation (IVIVE) methods.  Field-based LOEs include the BMF, bioaccumulation factor (BAF), and the Trophic Magnification Factor (TMF). In silico LOEs include quantitative structure-activity relationships (QSARs) for the BCF and the biotransformation rate constant (kB) and mass balance bioaccumulation (toxicokinetic) models.

The BAT was developed with stakeholder involvement including representatives from academia, government and industry with research support from Cefic-LRI The BAT is implemented (coded) in Visual Basic for Applications (VBA) and the Graphical User Interface is designed in Excel™. The BAT User Manual and Quick Start Guide are embedded as pdfs within the Excel file. This Quick Start Guide can be considered to expedite the use of the BAT; however, all BAT users are strongly encouraged to read the User Manual before using the BAT. A recent presentation of the BAT system given to stakeholders is available here.

How to Cite:

– Armitage JM, Toose L, Embry M, Foster KL, Hughes L, Arnot JA. 2018. The Bioaccumulation Assessment Tool (BAT) Version 1.0. Developed by ARC Arnot Research and Consulting Inc., Toronto, ON, Canada

BAT Ver.1.0 was publicly released October 2018.

Do you already have a password? Click here.



* Please carefully follow all instructions on the download request form

Risk Assessment IDentification and Ranking (RAIDAR) Model

RAIDAR is an evaluative, regional-scale, mass balance model for screening level exposure and risk assessment.

Risk Assessment IDentification and Ranking – Indoor and Consumer Exposure (RAIDAR-ICE) Model

RAIDAR-ICE is a versatile, efficient tool for screening and prioritization of neutral organic chemicals based primarily on near-field direct and indirect exposure pathways and associated potential human health concerns.

The Indoor Chemical Exposure Classification/Ranking Model (ICECRM)

The Indoor Chemical Exposure Classification/Ranking Model (ICECRM) is a steady-state model for the screening-level assessment of near-field human exposure to neutral organic chemicals released indoors. ICECRM adopts an existing multimedia indoor chemical fate model and couples it with exposure routes to humans and a human toxicokinetic model.

FHX (Far-field Human eXposure) model

FHX is an evaluative, regional-scale, mass balance model for screening level far-field human exposure assessment.

FHX-CAN (Far-field Human eXposure in Canada) model

FHX-CAN is an evaluative, regional-scale, mass balance model for screening level far-field human exposure assessments in selected regional areas of Canada.

In Vitro Mass Balance Model (IV-MBM)

In Vitro Mass Balance Model (IV-MBM) was designed to simulate the distribution of neutral organic chemicals in the in vitro test systems based on i) the partitioning properties of the chemical and ii) the properties (e.g., volume fraction of serum albumin in the test medium) and dimensions of the in vitro test system.

AQUAWEB (Aquatic Food Web) model

AQUAWEB is a site-specific bioaccumulation model for aquatic food webs and provides estimates of chemical concentrations in organisms of aquatic food webs from chemical concentrations in the water and the sediment. The model is presented in rate constant format for assessing the bioaccumulation of non-ionic hydrophobic organic chemicals at steady-state.

Bioconcentration for Ionizable Organics (BIONIC)

The BIONIC model estimates the bioconcentration factor (BCF, L/kg) of neutral organic and ionizable organic chemicals (IOCs) in fish and is an outcome of the CEFIC-LRI ECO21 project which ended in 2015.


San Francisco Bay Food Web Bioaccumulation model

This model was developed to assess the effects of PCBs in wildlife and fishermen in San Francisco Bay and to identify potential risk management actions. The objective of this model is to estimate the concentrations of PCBs in a set of key species that reside in the Bay as a result of PCB concentrations in sediments and water in the Bay. 

Screening-level BCF and BAF models

This model provides screening-level estimates of the bioaccumulation factor (BAF) for generic fish species in lower, middle and upper trophic levels of aquatic food webs. The model also provides screening-level estimates of the bioconcentration factor (BCF) for water exposures only (i.e., in laboratory bioconcentration tests).

Human Biotransformation and Total Elimination Half-life QSARs (IFS)

The whole body, total elimination half-life (HLT) and the whole body, primary biotransformation half-life (HLB) are key parameters determining the extent of bioaccumulation, biological concentration, and risk from chemical exposure.


Fish biotransformation rate constant (or half-life) QSARs

We have developed and published databases that have subsequently been used to develop and validate QSARs for predicting fish biotransformation half-lives from chemical structure. The first fish biotransformation half-life QSAR is included in the BCFBAF module of the U. S. EPA’s EPI Suite™ software package.


In Vitro-In Vivo Extrapolation: Fish Bioconcentration Factor (IVIVE – Fish BCF) Model

The OECD has developed standardized test guidelines for measuring in vitro biotransformation rates using S9 and hepatocyte (HEP) assay systems from rainbow trout liver tissues. Models are required to extrapolate the in vitro rates to in vivo liver clearance and whole body biotransformation rates and to incorporate these rates in toxicokinetic models to calculate bioaccumulation assessment endpoints such as the bioconcentration factor (BCF). One model for extrapolating in vitro S9 and HEP biotransformation rates to fish BCFs is the one developed by Nichols et al. 2013. An on-line version of the Nichols et al., 2013 IVIVE-Fish BCF model is available.

Limitations of liability and disclaimer of warranty
ARC Arnot Research & Consulting Inc. and all associated collaborators do not guarantee, warrant, or make any representations, either expressed or implied, regarding the use, or the results of the use of the materials provided with regards to reliability, accuracy, correctness, or otherwise. There are no warranty rights granted to users of the models or databases provided.

Users assume the entire risk as to the results and performance of the models and databases. ARC Arnot Research & Consulting Inc. and all associated collaborators are not liable under any circumstances, for any damages whatsoever, arising out of the use, or the inability to use, the models and databases provided, even if advised of the possibility of such damages.