CK12 Earth Science

Table 19.2: (continued)

Type of Hazardous Waste Example Why it is Hazardous

Medical wastes Surgical gloves, wastes con-

taminated with body fluids

such as blood, x-ray equip-

ment

Toxic to humans and other

organisms; may be chemi-

cally active

Paints Paints, paint thinners, paint

strippers, wood stains

Toxic; flammable

Dry cleaning chemicals Many various chemicals Toxic; many cause cancer in

humans

Agricultural chemicals Pesticides, herbicides, fertil-

izers

Toxic to humans; can harm

other organism; pollute soils

and water

Impacts of Hazardous Waste

Many hazardous waste materials have serious impacts on human health. They often cause
cancer and can also cause birth defects. They can make people sick for very long times.
Breathing the air or drinking the water that is contaminated with hazardous waste is a
major health threat.

Two chemicals that are especially toxic in the environment are lead and mercury. Lead
harms people by damaging their brain and nervous system. Lead is especially harmful in
children under the age of six; about 200 children die every year from lead poisoning. Lead
was once a common ingredient in gasoline and paint (Figure19.11). In the 1970’s and
1980’s, the United States government passed laws completely banning lead in gasoline and
paint. This has prevented the lead poisoning of millions of children in the United States.
However, several other countries still use gasoline with lead in it. Also, homes built before
the 1970’s may contain paint that has lead in it. These still pose a threat to human health.

Mercury is a pollutant affecting the whole world (Figure19.12). Mercury enters the envi-
ronmentfromvolcaniceruptions, burningcoalandfromwasteproductslikeoldbatteriesand
electronic switches. It is also found in old discarded electronic appliances like television sets.
Like lead, mercury also damages the brain and impairs nervous system function. Mercury
often accumulates in fish, so people and other animals that eat the fish then are in danger
of getting the mercury in their own bodies.

Preventing Hazardous Waste Pollution

The United States is currently the world’s largest producer of hazardous wastes. However, as
China becomes more industrialized, it may take over the number one spot. Countries with