males then compete with wild males to mate, ultimately reducing the next
generation’s population.
CASE STUDY
AFRICAN SLEEPING SICKNESS: Sleeping sickness is a parasitic disease
in humans. Caused by a protozoa and transmitted by the tsetse fly, the disease
is endemic in certain regions of sub-Saharan Africa, covering about 36
countries and 60 million people with about 40,000 people dying from the
disease every year. Studies of the tsetse fly show that females generally only
mate once in their lifetime. To control this disease, male tsetse flies are
sterilized through radiation. These sterilized male flies are then released into
areas where sleeping sickness is prevalent and mate with the females. Because
the male is sterile, and the females mate only once, the population of tsetse
flies in the affected area drops dramatically.CARBAMATES
Carbamates, also known as urethanes, affect the nervous system of pests. 100
grams of a carbamate has the same effect as 2,000 grams of a chlorinated
hydrocarbon such as DDT. Carbamates are more water soluble than chlorinated
hydrocarbons, which brings a greater risk of them being dissolved in surface
water and percolating into groundwater.
CASE STUDY
On December 2, 1984 at the Union Carbide pesticide plant in Bhopal, India, a
leak of chemicals from a plant manufacturing a carbamate pesticide leaked,
which resulted in the exposure of hundreds of thousands of people. Roughly
8,000 people have since died from gas-related diseases with 200,000 people
having permanent injuries.CHLORINATED HYDROCARBONS AND OTHER PERSISTENT ORGANIC COMPOUNDS
(POPS)
Chlorinated hydrocarbons, such as the pesticide DDT, are synthetic organic
compounds that belong to a group of chemicals known as persistent organic
pollutants or POPs. POPs are organic compounds that are resistant to
environmental degradation through chemical, biological, and photolytic
processes. Because of this, they have been observed to persist in the