There are places where toxin levels are high enough that entire food sources must be avoided.[1]

Bioaccumulation is when the concentration of chemicals increases within an organism or species. This can occur when toxic substances are ingested.[2] These toxic substances are very difficult for organisms to excrete, therefore, accumulate in their tissues. One common pollutant that bioaccumulates is mercury, which specifically accumulates in fish. Organic compounds and metals can both bioaccumulate.

Bioaccumulation vs Biomagnification

An important result of bioaccumulation is biomagnification. This describes when toxins magnify upward in the food chain—whereas bioaccumulation describes when toxins accumulate within a single organism.

Biomagnification is a very closely related idea. To learn more about it, click here.

For Further Reading


  1. Cleanmarine internet:
  2. D. Mackay and a. Fraser, “Bioaccumulation of persistent organic chemicals: mechanisms and models,” Environmental Pollution, vol. 110, no. 3, pp. 375–391, Dec. 2000.

Authors and Editors

Bethel Afework, Jordan Hanania, Braden Heffernan, James Jenden, Kailyn Stenhouse, Sumaya, Jason Donev
Last updated: January 4, 2019
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