THE ANTHROPOCENE - Plastics and Environmental Sustainability - page 20

and services for consumers. With renewables, managed harvesting or use
should not present a special problem. But with scarce materials such as
rare earth oxides, a problem that parallels that of fossil fuels exists. Metals
occur as concentrated ores; their use entails extracting them and using
them often in minute quantities in various products and then dispersing
them as waste into theenvironment. Post-use metals are very expensive and
tedious to recover. The global and US consumption of selected materials of
construction in 2011 is given in Table 1.1 .

Table 1.1 Approximate Global Use of Selected Building Materials
(2011 Data)

Region Cement Roundwood Steel Plastic Aluminum

World (BMT) 3.6 1.74 1.52 0.28 0.04

United States
(MMT)

72 145 90 47.5 3.6

The table is based on data from “Materials and the Environment”
(www.forestinfo.org)

Itisinterestingtocalculatethetotalembodiedenergy(GJ)indifferenttypes
of building materials based on the data in Table 1.1 . The bar diagrams in
Figure 1.8 compares the global materials-use energy and carbon emissions
for selected materials based on 2011 data. In numerous applications, the
functionality demands of the product can be delivered using less-scarce
and lower energy-intensive substitutes such as plastics. In Chapter 3 , the
advantage of using plastics as a substitute material will be discussed in
greater detail.