Non Degradable pollutants
Pollution caused by substances, on which biotic and abiotic agencies of decomposition art ineffective, is a unique type of pollution. Chemicals causing it are a part and parcel of inorganic matter which constitutes this planet. Toxic trace elements and heavy metals come under the category of non-degradable pollutants.
The problem caused by these elements is in fact due to their concentration in the environment in bio-available state. They cannot be destroyed. Dispersal and dilution in such a manner that these toxic elements are no longer available to the biosphere in toxic state and quantities eliminate this type of pollution.
Hydrogen, carbon, nitrogen, oxygen, sodium, potassium, magnesium, phosphorus, sulphur and calcium collectively constitute about 99.5% of a living organism by weight. Fourteen other elements which include: boron, cobalt, copper, fluorine, silicon, vanadium, chromium, manganese, iron, selenium, molybdenum, tin, iodine and zinc make up the remaining 0.5% of the mass of a living organism.
These elements are considered essential trace elements for the biosphere. The rest of the elements which occur on this planet are either non-essential for the growth and development of living beings or their function within a biological system has not been demonstrated so far. Some of these trace elements whether essential or non-essential when present in the environment in bio- available state above a certain concentration become harmful to the living organisms.
