Zinc in a sustainable society

An Ask the Expert feature with International Zinc Association

Dr Andrew Green, Director of Environment and Sustainability for the International Zinc Association explains the advantages of using zinc.

Sustainable development as a guiding principle has become a societal, regulatory and market driver. Markets are increasingly shifting toward high-performing and environmentally responsible products. Thus the environmental and social attributes of materials and products are now influencing design and purchasing decisions. The zinc industry welcomes this new paradigm because zinc – both as a raw material and in the final product form – has the characteristics that sustainable development demands. The International Zinc Association (IZA) has been working hard over the last few years to develop a Life Cycle Inventory (LCI) database for zinc and zinc containing products that provides end users with the data they need to assess the sustainability of zinc and its final products.

Zinc is a versatile material that is an integral part of the building products and construction industries. Zinc coatings stop steel from corroding, vastly extending the durability and life expectancy of the galvanised steel products. With low cost and energy consumption zinc castings produce strong, precision building products that are used everywhere, from door handles and locks to plumbing fixtures and window hardware. Zinc sheet, used in roofing and siding, provides a beautiful and protective covering that lasts for generations. And, all of these zinc products, when they do reach the end of life, are 100 percent recyclable, over and over again without any loss of metal quality. 

Zinc has another attribute that is arguably the most important of all, zinc is essential for life. Every living organism – humans, animals, plants and the smallest micro organisms – need zinc. Zinc is an essential trace element (the adult body contains two to three grams of zinc) that is present in organs, tissues, bones, fluids and cells. Zinc is essential for proper functioning of the immune systems, enzymes and the perpetuation of genetic material. Zinc deficiency is recognised by the World Health Organisation as a leading cause of illness and disease in developing countries. Zinc deficiency in agricultural soils impairs crop yield and quality, as well as reduces zinc content in the crops themselves. The international zinc industry actively supports dietary and agricultural zinc enhancement programmes to address these major human health concerns, primarily in the developing world. 

But how does zinc improve the sustainability of construction projects? Let’s look at one zinc end use application – hot dip galvanising of fabricated steel structures. The galvanising process produces a tough, tenacious corrosion resistant zinc coating that is an impervious barrier between the steel and the corrosive atmosphere. These excellent mechanical properties combined with zinc’s low corrosion rate ensure that in most environments galvanising will provide a maintenance free coating life. Without this level of protection, which is most often the case with other protective coating systems, financial resources are consumed through repeated maintenance operations, either painting or repairs. In addition to the financial costs, maintenance is often a hazardous procedure on elevated steel structures and causes disruptions to the public. Maintenance also has a direct life cycle energy cost. A German study has shown that 57 tonnes of carbon dioxide would be saved if 500 tonnes of steel used in a car park were galvanised rather than painted.

Similar analysis can be performed on other zinc containing products and the zinc industry encourages architects and building engineers to conduct these studies and IZA is available to assist. The zinc industry through IZA’s Zinc for Life programme (www.zincforlife.org) provides LCI data on primary zinc production as well as on downstream transformation industries that produce the final product. The zinc industry is committed to providing stakeholders with the facts and figures they need to make environmentally and socially responsible choices on the building products and construction designs that are used.

Zinc is durable, recyclable and essentiality well positioned as a material of choice for a sustainable society.

The International Zinc Association (IZA) is a non-profit organization based in Brussels, Belgium and Durham, North Carolina, USA. IZA’s team of internationally recognized experts conduct programmes in environment and sustainable development, technology and market development and communications. For more information, please visit www.zincworld.org.