Biomagnification Factor Calculator

Biomagnification Factor Calculator

Biomagnification tracks how a contaminant's concentration changes as it moves up a food chain, from prey to predator - distinct from bioaccumulation, which compares an organism to its environment rather than to what it eats.

BMF = Concentration in Predator / Concentration in Prey

Example

10 mg/kg in the predator, 2 mg/kg in its prey:

BMF = 10 / 2 = 5.0 (biomagnification is occurring)

Why It Compounds Up the Food Chain

A BMF greater than 1 at each trophic step compounds multiplicatively as you move up the food chain - this is exactly why top predators like large fish, birds of prey, and marine mammals (and ultimately humans who consume them) can accumulate contaminant levels many times higher than what exists at the base of the food chain, even when the base concentration itself seems negligible.

Well-Documented Examples

Mercury and certain persistent organic pollutants are classic examples of substances that biomagnify strongly through aquatic food chains - this is the underlying reason behind fish consumption advisories that specifically warn about larger, longer-lived predatory fish species (like tuna or swordfish) rather than smaller species lower in the food chain.