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Copper and human health
The healthly threshold is 4mg of Copper per liter of drinkable water. Public is usually exposed to an average of 0.7mg of Copper per liter. The World Health Organisation recommends a concentration of 2mg/l for Copper.
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The principal source of exposure for the consumer (the population in general) is food and drinking water. For adults, it is recommanded to absorb a minimum of 1mg per day and the maximum threshold is 11mg. In fact, consumers absorb between 0.6 mg and 2mg per day, uncovering there might be a potential deficit of copper absorbtion.
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Copper isn't a CMR substance (carginogenic, mutagenic or toxic for reproduction ) or a PBT substance (persistant, bioaccumulative and toxic).
Copper and the oceans
Copper is a natural component present in the oceans amongst other substances.
We find 11 main components in ocean waters.
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Chlorine |
2,5x10¹⁶ tons |
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Sodium |
1,4x10¹⁶ tons |
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Magnesium |
1,7x10¹⁵ tons |
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Calcium |
5,4 x 10¹⁴ tons |
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Potassium |
5,0x10¹⁴ tons |
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Silicone |
2,6x10¹² tons |
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Zing |
6,4x10⁹ tons |
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Copper |
2,6x10⁹ tons |
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Iron |
2,6x10⁹ tons |
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Manganese |
2,6x10⁸ tons |
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Cobalt |
2,5x10⁷ tons |
It is considered that only 1% of the Copper present in the oceans is going to be transformed into Copper Oxyde or Dioxyde. This copper oxide is going to evolve by itself in different ways :
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Absorption by organic elements or trace elements.
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Evolves as a binding agent for complex organic systems as Cu- Fulvic acid.
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Evolves as a binding agent for complex non-organic systems such as CuOH + .
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Reduction en ( Cu)I.
These different transformations in the oceans allow us to consider that Copper is :
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Non cumulative in the food chain.
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Non persistent because it makes his way through different bio-chemical mechanisms.
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Potentially toxic at a concentration level of 5µg/l (rate administered by the European Union), whereas TBT is toxic above 0.002µg/l. However, the concentration of Copper in sea water is subject of contradictory interpretations and evaluations. For example, the authorites of the Bay of San Diego in the US consider that high copper concentration is responsible for reducing underwater. In the Red Sea, the rate of naturally found Copper is 100 times more important than San Diego rate, and has not yet slowed down (and this after thousands of years) the development of an outstanding biodiversity, specially around reef corals.
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