Essential for life
Copper is essential for all forms of life. It exists naturally in the environment being essential for the metabolism of animals, plants and humans. It is regulated by homeostasis and does not accumulate in food chain. In agriculture it is widely used to improve soil quality and as food supplement to keep cattle healthy. Copper is a natural essential element, which should not be mistaken with manmade chemicals or toxic heavy metals, which can accumulate in humans, sea life, and plants. Copper is heavy by its density (8,94 g/cm3), but this has nothing to do with hazard or environmental properties.
Bioavailability
In nature, copper appears in the form of solid mineral and as a trace element in plants, organisms and water. It is primarily the dissolved ionic form that is available to be absorbed by humans, animals and plants. Absorption, storage and excretion of copper are completely normal phenomenon in the natural cycle. Being released to nature in ion form copper will be quickly bound to particles or minerals which are no longer bioavailable.
Natural cycle of copper
Runoff and patina
Copper sheet exposed to atmospheric conditions gradually forms a surface layer of corrosion, known as the patina. The prevailing concentrations of air pollution and the environmental conditions essentially determine the composition and protective properties of the patina. Owing to the environmental interaction, a small part of the patina dissolves and is released from the copper surface during precipitation. This is called the runoff. The sulfur dioxide in the atmosphere is one major factor that influences the corrosion process. A substantial decline of the sulfur dioxide in the air since the 1980’s has resulted in a substantial decrease in the runoff.
Entries in the environment
The copper voluntary risk assessment has shown that only 1% of the overall amount of copper that enters into the environment from anthropogenic sources can be attributed to copper from outdoor designs. If the natural seasonal process (falling of leaves) is taken into account this portion is even less. Research also shows that the bioavailable portion of copper in the runoff is quickly and considerably reduced and stays in the immediate vicinity of the roof.
Life cycle of copper
The copper industry has compiled up-to-date life cycle data for its products. Production data has been collected from across the copper industry in co-operation with recognised life cycle consultants using standardized methodology. The long life and recyclability of copper products have a positive impact on their life cycle, from cradle to grave. For more information please visit: www.copper-life-cycle.org.
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