Cadmium is the 48th element on the periodic table. It is a poisonous metal and within the environment it is classified as a harmful pollutant. It can be released into the environment from natural sources like volcanoes, and from human activities such as fertilizer use, fossil fuel combustion, mining and smelting, waste incineration, and even tobacco smoking.  The percentages of total emissions can be seen via the data visualization below.
Some properties of cadmium include:
|Density (at 0oC)||8.69 g/cm3|
|Boiling point||1040 K|
|Melting point||594.22 K|
Due to its toxicity cadmium use in industry has been limited, however it is still used for some applications. Most uses involves combining it with nickel within nickel-cadmium batteries. It is also used in control rods within nuclear reactors because of its neutron absorbing properties. Cadmium is used outside of the energy sector in creating corrosion resistant metals and even brightly coloured paints.
Cadmium is very poisonous to humans, and its target organ is the kidney. It may either be inhaled or ingested which may lead to several complications such as kidney stones, osteopororis, softening of the bones and even lung cancer. High levels of inhalation result in complications of breathing due to chronic obstructed airway disease, and can also cause effects like pulmonary oedema which can be lethal.
Emissions of cadmium have been reduced drastically in recent years. To see this, along with more data on cadmium and other pollutants, click here. These reduced emissions are in part due to the awareness of the toxic effects, however there is still more that can be done. Recycling of cadmium products should always be done after the product's lifetime, and it should never be disposed of improperly.
The chart below shows the human releases of Cadmium in Canada.
For more information on cadmium, please see the International Cadmium Assocation.