Difference between revisions of "Heavy metals"
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| − | Heavy metals contain both biological essential as not biological essential metals. Biological essential heavy metals include | + | Heavy metals contain both biological essential as not biological essential metals. Biological essential heavy metals include copper (Cu), iron (Fe) and zinc (Zn). Not biological essential heavy metals include lead (PB), [[mercury]] (Hg),[[cadmium]] (Cd) and tin (Sn). |
Heavy metals enter the sea usually through riverine influx, atmospheric deposition, volcanic activity and [[anthropogenic]] activities. Common anthropogenic sources of these elements are mining, melting, automobile emissions, sewage, [[antifouling paints]],... . | Heavy metals enter the sea usually through riverine influx, atmospheric deposition, volcanic activity and [[anthropogenic]] activities. Common anthropogenic sources of these elements are mining, melting, automobile emissions, sewage, [[antifouling paints]],... . | ||
When present above threshold concentrations, all heavy metals are potentially toxic. The exposure of marine organisms to toxic levels of metal contaminants can cause damage to tissue, inability to regenerate damaged tissue, growth inhibition, damage to DNA. Although most marine organisms marine organisms tend to accumulate heavy metals from the environment, they are capable to store, remove (trough feces, eggs, or molting) or detoxify (through [[metallothionein|metallothioneins]]) many of them. | When present above threshold concentrations, all heavy metals are potentially toxic. The exposure of marine organisms to toxic levels of metal contaminants can cause damage to tissue, inability to regenerate damaged tissue, growth inhibition, damage to DNA. Although most marine organisms marine organisms tend to accumulate heavy metals from the environment, they are capable to store, remove (trough feces, eggs, or molting) or detoxify (through [[metallothionein|metallothioneins]]) many of them. | ||
Revision as of 17:37, 8 July 2009
Heavy metals contain both biological essential as not biological essential metals. Biological essential heavy metals include copper (Cu), iron (Fe) and zinc (Zn). Not biological essential heavy metals include lead (PB), mercury (Hg),cadmium (Cd) and tin (Sn). Heavy metals enter the sea usually through riverine influx, atmospheric deposition, volcanic activity and anthropogenic activities. Common anthropogenic sources of these elements are mining, melting, automobile emissions, sewage, antifouling paints,... .
When present above threshold concentrations, all heavy metals are potentially toxic. The exposure of marine organisms to toxic levels of metal contaminants can cause damage to tissue, inability to regenerate damaged tissue, growth inhibition, damage to DNA. Although most marine organisms marine organisms tend to accumulate heavy metals from the environment, they are capable to store, remove (trough feces, eggs, or molting) or detoxify (through metallothioneins) many of them.
