Zinc is Essential for the Environment
All life on earth has evolved in the presence of natural levels of zinc. Due to its general availability to organisms and unique characteristics, zinc has an essential role in various biological processes. As such, zinc is an essential element for all forms of life, from the smallest micro-organisms to man.
The Natural Cycling of Zinc
Organisms take up the essential elements they need from their environment, which means directly from air, water, soil, or from food. When their cellular requirements for these elements are satisfied, growth and development are optimized.
The zinc industry is continually funding research to develop information and state-of-the-science methodologies which allow zinc’s bioavailability to be predicted in a range of environmental conditions, such as in water and sediments.
Zinc in the Environment
The environmental impact of zinc – and of all essential elements – cannot be assessed in the same way as man-made chemical compounds. Because zinc occurs naturally, eliminating it from the environment would not be possible. Moreover, because zinc is essential, achieving such a goal would ultimately lead to detrimental effects throughout an ecosystem. In other words, “less” is not necessarily “better”.
Elevated levels of zinc in the environment occur because of various man-made activities, and sources of emissions include municipal and industrial effluents, historical impurity, mining activities, geology and diffuse sources (unintentional sources that are not directly connected with zinc production or manufacturing). An extensive risk assessment of zinc in Europe concluded that “the current uses of zinc and zinc compounds do not [by themselves] lead to the elevated regional levels found in surface water and sediment”. The distribution, transport and effects (bioavailability) of zinc in water, sediment and soil depend largely on the site-specific chemical and physical characteristics of the environment and an organism’s condition (e.g. age, size, prior history of exposure, etc.). For these reasons, environmental assessment of zinc must take these factors into account to be meaningful.
For more information, please visit http://www.zinc.org/sustainability.