Environmental Problem Associated with Waste Tire
1. Mosquitoes Disease
2. Fire Hazards
In 1990, over 240 million scrap tires were discarded in the United
States and approximately 3 billion waste tires had accumulated in stockpiles.
Each year, over 77% of the annual production of scrap tires, about
188 million tires per year, were landfilled, stockpiled or illegally dumped1).
Tires are bulky, and 75% of the space a tire occupies is void, so that the landfilling of scrap tires has several difficulties:
By 1998, 48 states had passed scrap tire laws, regulations or amendments
and 34 states provide market incentives to regulate scrap tires.
Sixty percent of scrap tires have been recycled and the stockpiles have
decreased to about 500 million tires2).
Even though the situation in the United States has improved, tire stockpiles
still exist and pose a threat to public health and safety.
Health Hazards
Tire piles are excellent breeding grounds for mosquitoes. Because
of the shape and impermeability of tires, they may hold water for long
periods of time providing sites for mosquito larvae development.
In the southern U.S. two exotic species predominate in tires.
These two species (Aedes aegypti and Aedes albopictus) are known to be
the principal vectors of Yellow Fever and Dengue disease which afflict
millions of people in the tropics.
In temperate regions of North America, Aedes triseriatus (the native
"Eastern Treehole Mosquito") and Aedes atropalpus predominate in scrap
tires3).
Tire stockpiles also have contributed to the introduction of non-native
mosquito species when used tires are transported to the United States.
The new species are often more difficult to control and spread more disease.
Aedes albopictus (the "Asian Tiger Mosquito") merits special consideration.
This species was accidentally transported from Japan to the western hemisphere
in the mid-1980's in shipments of used tires. It has since become
established in at least 23 states. It is considered the nation's
most dangerous species3).
It is obvious that the elimination of scrap tire piles will eliminate
a prolific mosquito habitat along with the associated disease risks.
It is also clear that the spread of the Asian Tiger Mosquito has been hastened
by interstate shipments of
scrap tires. Many states have banned importation of scrap tires for
this reason.
If elimination of tire piles is not feasible, mosquito abatement programs
may be required to suppress mosquito populations at tire piles. This task
is problematic and costly, particularly for large piles.
Fire Hazards
Waste tires and waste tire stockpiles are difficult to ignite. However,
once ignited, tires burn very hot and are very difficult to extinguish.
This is due to the 75% void space present in a whole waste tire, which
makes it difficult to quench the tires with water or to eliminate the oxygen
supply. In addition, the doughnut-shaped tire casings allow air drafts
to stoke the fire.
A large tire fire can smolder for several weeks or even months, sometimes
with dramatic effect on the surrounding environment. In 1983, a 7-million-tire
fire in Virginia burned for almost nine months, polluting nearby water
sources.
The air pollutants from fires include dense black smoke which impairs visibility and soils painted surfaces. Toxic gas emissions include polyaromatic hydrocarbons, CO, SO2, NO2, and HCl. The heat from tire fires also causes some of the rubber to break down into an oily material. Prolonged burning increases the likelihood of surface and groundwater pollution by the oily material. Using water to extinguish a tire fire is often a futile effort, since an adequate water supply is frequently unavailable. Smothering a tire fire with dirt or sand is perhaps the best current option for extinguishing tire fires. The sand or dirt is moved with heavy equipment to cover the burning tires. This technique does not contribute as greatly to the oil run-off problem and is generally faster and cheaper than foams or water4).