Chapter 1, Section 2
The Environment
One unintended consequence of new technologies is the production of pollutants. A pollutant is a material found in air, water, or soil that is harmful to humans or other organisms. Chemists help to identify pollutants and prevent pollution.
Identify Pollutants
Lead is a pollutant with a long history. The Romans used lead pipes for plumbing and stored their wine in lead-glazed vessels. Brain damage from lead poisoning may have caused Roman rulers to make bad decisions, which led to the fall of the Roman Empire. Until the mid-1900s, lead was used in many products, including paints and gasoline. A study done in 1971 showed that the level of lead that is harmful to humans is much lower than had been thought, especially for children. Low levels of lead in the blood can permanently damage the nervous system of a growing child. This damage causes many problems, including a reduced ability to learn.
Prevent Pollution
The use of lead paint in houses was banned in 1978. Using lead in gasoline and in public water supply systems was banned in 1986. Today, the major source of lead in children is lead-based paint in about 39 million homes built before 1978. When children play with flakes of peeling paint or touch surfaces covered with paint dust, they can transfer the paint to their mouths with their fingers. The strategies used to prevent lead poisoning include testing children’s blood for lead, regulation of home sales to families with young children, and public awareness campaigns with posters like the one in Figure 1.12. The graph in Figure 1.13 shows the results of these efforts.
Figure 1.12 This poster was used to warn people about the danger to children from lead-based paint.
