Steel + Zinc: The Healthy Metal
What is Zinc?
Before we examine the impact of hot-dip galvanized steel to the environment, it is import to understand the primary component of the hot-dip galvanized coating – zinc. Zinc is a healthy metal, infinitely recyclable without the loss of any physical or chemical properties. Natural, essential, and abundant, approximately 30% of the world’s zinc supply comes from recycled sources annually, and 80% of zinc that can be recycled is reclaimed.
Zinc is Natural
Zinc, the 27th most abundant element in the Earth’s crust, naturally exists in air, water, and soil. Most rocks and many minerals contain zinc in varying amounts. Approximately 5.8 million tons of zinc are naturally cycled though the environment annually by plant and animal life, rainfall, natural phenomena, and other activity. During the course of evolution, all living organisms have adapted to the zinc in their environment and use it for specific metabolic processes. The amount of zinc present in the environment varies from place to place and season to season.
Zinc is Essential
Zinc is also essential to life for humans and even the smallest microorganisms. Zinc aids in digestion, reproduction, kidney function, breathing, diabetes control, taste, smell, and much more. Although zinc in excess can be detrimental, zinc deficiency is a much greater concern. The World Health Organization (WHO) estimates 800,000 people in developing countries die each year due to lack of zinc in their diet.
Zinc is Common
Zinc is common in day-to-day life, in fact, zinc oxides and other compounds are used in a number of household products. Zinc oxide blocks more UV rays than any other single ingredient, thus it is common in sunscreens. Zinc is also used in cosmetics, tires, the treatment of sunburns, diaper rash, acne, cold sores, dandruff, the common cold, burns, other wounds, and much more. Additionally, one of the oldest and most common uses for zinc is in construction.
Infinitely Renewable Resources
In addition to being natural and abundant, both zinc and steel are infinitely recyclable without the loss of any physical or chemical properties. This means rather than being down-cycled into other, lesser product, zinc and steel can be used as zinc and steel again and again without compromising their integrity. Therefore, hot-dip galvanized steel is a cradle-to-cradle product, as there is essentially no “grave” for the zinc or steel.
The 100% recyclability of hot-dip galvanized steel is a great benefit to minimizing environmental impact, but it is only half of the story. The ability for both zinc and steel to be recycled is important, but to capitalize on the positive contribution, they must actually be reclaimed for reuse. Therefore it is important to consider both the recycled content, amount of a product produced from recycled sources, and reclamation rate, how often a product is actually recycled at the end of its useful life. Steel is the most recycled material in the world, and zinc has a very high reclamation rate – and often the zinc and steel are put right back into use.