Travis and Arms revisited: a second look at a widely used bioconcentration algorithm

Area of Science:

• Environmental Chemistry
• Toxicology
• Risk Assessment

Background:

• The octanol-water partition coefficient (Kow) is crucial for predicting organic compound uptake in food chains.
• Established equations by Travis and Arms (1988) estimate biotransfer factors but faced scrutiny regarding validity and applicability.
• Previous assessments by the US Environmental Protection Agency (EPA) highlighted the need to re-evaluate these biotransfer estimation methods.

Purpose of the Study:

• To validate the original Travis and Arms equations for estimating organic compound transfer into milk and beef.
• To assess the appropriateness of these equations across the full range of log Kow values.
• To update biotransfer factor equations using recent literature and expanded datasets.

Main Methods:

• Literature review of existing studies on organic compound biotransfer.
• Validation of the original Travis and Arms (1988) biotransfer equations.
• Data compilation from recent literature to supplement the original dataset.

Main Results:

• Evaluation of the technical validity and reproducibility of the Travis and Arms equations.
• Identification of limitations in the current application of these biotransfer estimation models.
• Development of updated equations to improve accuracy and expand applicability.

Conclusions:

• The original Travis and Arms equations require validation and potential updates for reliable biotransfer factor estimation.
• Addressing the identified limitations and incorporating current data are essential for reducing uncertainties in risk assessments.
• Updated equations will enhance the prediction of organic chemical uptake in food products, particularly when empirical data are scarce.