A chlorinated hydrocarbon with a half-life of 15years (1).
Comes into ecosystems as a synthetic pesticide. (1)
Almost non-toxic to humans but damaging to the nervous systems
of insects. (1)
Exemplary Case: Long Island Estuary, U.S.A., 1967
- extensive use of the pesticide over the years
- biomagnification factor of DDT: 800x
- effects: DDT was absorbed by zooplankton and was biomagnified
as it moved through crustaceans and fish -> hell-thinning in
birds, the last trophic level (ospreys, eagles, etc.) ->
inability to brood
- solution: banning of DDT in the U.S.A. in 1972 -> birds
gradually recovered. The bold eagle came back (1)
http://marine.usgs.gov/fact-sheets/fs41-98/
Radioactive Materials
Unstable substances that emit energy
Damage all kinds of living tissue
Exemplary Case: The Chernobyl Accident,
Ukraine, 1986
- large amounts of caesium-137 released in the air and brought
around northern Europe
- resulted in genetic damage in fish species and bird species
that feed on them in the Baltic Sea
- in Bulgaria, there was a ban on milk products because there
were biomagnified as cows consumed contaminated grass
- solution: the Chernobyl NPP plant was sealed, and milk and
meat consumption was restricted over Europe to prevent human
casualties. (5)
