Figure 23.18 Biomagnification of DDT. When DDT was widely used to control insects, it could be found in very low concentrations in the water. However, its concentration increases in particles with which it binds in the water such as algae. At each higher trophic level, the insecticide becomes more concentrated.

Data from G. M. Woodwell, C. F. Wurster, Jr., and Peter A. Isaacson, DDT residues in an East Coast estuary: A case of biological concentration of a persistent insecticide, Science 156 (1967): 821–824.