From Coastal Wiki
Definition of heptachloronorbornene:
Heptachloronorbornene is a very hydrophobic chemical intermediate in the syntheses of the stable chlorinated cyclodiene insecticides such as aldrin and isodrin.
This is the common definition for heptachloronorbornene, other definitions can be discussed in the article
Little is know about its environmental effects. It has been shown to display a very high tendency to bioaccumulate, and was found in edible fish from rivers in the USA. 
Environmental standards and legislation
Included in the OSPAR list of substances of priority action
- ↑ Harald J. Geyer, Gerhard G. Rimkus, Irene Scheunert, Andreas Kaune, Karl-Werner Schramm, Antonius Kettrup, Maurice Zeeman, Derek C.G.Muir, Larry G. Hansen, Donald Mackay;Bioaccumulation and Occurrence of Endocrine-Disrupting Chemicals (EDCs), Persistent Organic Pollutants (POPs), and Other Organic Compounds in Fish and Other Organisms Including Humans. The Handbook of Environmental Chemistry,Vol. 2 Part J, Springer-Verlag Berlin Heidelberg 2000
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