A restricted substance is — a material that is restricted by either 1) government (via policy or regulation) due to its impact on the environment, human health or public safety; 2) stakeholder such as an NGO (via standards or simply public opinion) due to its impact on health or the environment; or 3) due to its limited availability as a natural resource.
Organic - (animal [angora, down], lumber [teak, Brazilian rosewood], cotton, seafood / fish, palm oil, cocoa)
Chemicals - (carcinogens, precursors to chemical weapons, SVHC – substances of very high concern [REACH])
Minerals - (conflict, rare earth)
Natural Resources - water