The models of toxic biomagnification (the process of chemical buildup in tissue over time as one animal eats another) used by regulators ignore differences in the way different species accumulate environmental chemicals. Many toxins are more likely to settle in the tissues of mammals than in algae, shellfish, and fish; hexachlorocyclohexane, for instance, a chemical in the pesticide lindane, does not accumulate to high levels in fish but does in polar bears, because it easily escapes in water but not in air.
The models of toxic biomagnification (the process of chemical buildup in tissue over time as one animal eats another) used by regulators ignore differences in the way different species accumulate environmental chemicals. Many toxins are more likely to settle in the tissues of mammals than in algae, shellfish, and fish; hexachlorocyclohexane, for instance, a chemical in the pesticide lindane, does not accumulate to high levels in fish but does in polar bears, because it easily escapes in water but not in air.