Pesticides are not the only cause responsible for ecological damage, but they are certainly one of the more serious causes. This kind of danger has long been ignored, until the reported fears have become tragic realities.

1. May 26, 2014FRANCESCA DI NICOLA 1
The fate of pesticides in the environment
PESTICIDE
Corso di Laurea Magistrale in
Valutazione d’Impatto e Certificazione Ambientale

2. May 26, 2014
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA 2
1.What are pesticides?
2.What happens to a pesticide after use?
3.Effect and alternative approaches

3. May 26, 2014 3
Pesticides are chemicals or biological agents used to:
 CONTROL
 REPEL
 ATTRACT
 KILL
Pesticides can harm the environment
and cause harm to humans.
They are a cause of serious losses that
are undergoing bee populations.
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

4. May 26, 2014 4
The pesticides used in an arable crops, can:
be absorbed by plants or be ingested by organisms
volatilize into the
atmosphere
be leached out
by rain or
irrigation water
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

5. May 26, 2014 5
The most useful index for quantifying pesticide
bioaccumulation is the partition coefficient KOW.
BIOACCUMULATION refers to the accumulation of pesticides, or
other organic chemicals in an organism.
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA
W
O
OW
a
a
K 

6. May 26, 2014 6
VOLATILIZATION is described by Henry's law constant.
Kh characterizes the tendency for a pesticide to move between the air and
the "soil water."
Kh is defined as:
the concentration of pesticide in
air divided by the concentration
in water.
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

7. May 26, 2014 7
When the pesticide enters soil, may enter into SOLUTION, or may be
ABSORBED by the soil particles. The "distribution coefficient" value is a
measure of how well the pesticide binds to soil particles.
The Kd is the "soil-water" partitioning coefficient.
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

8. May 26, 2014 8
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

9. May 26, 2014 9
PERSISTENCE defines the "lasting-power" of a pesticide.
The persistence is closely linked to the degradation of the
pesticide.
The degradation is measured in half-life and corresponds at
the amount of time it takes for
one-half the original amount of a
pesticide in soil to be deactivated.
Compounds with an extremely long
degradation time are considered
persistent.
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

10. May 26, 2014 10
Pesticides can enter into organism through body, or by
ingestion of contaminated food.
Farmers and their families reach toxic levels in their bodies.
The exposure can cause mutations, produce tumors, etc.
Other problems associated with insecticides is the ability of
populations of insects become resistant in a couple of
generations.
Most pesticides kill beneficial as well as pest species.
DISEASES TO
HUMANS
LOSS OF
EFFICACY
KILL BENEFICIAL
ORGANISMS
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA

11. May 26, 2014 11
Many alternatives are available to reduce the effects of pesticides on the
environment.
There are a variety of alternative pesticides, for example:
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA
• manually remove weeds and
pests from plants,
• setting traps and baits for
catching
• The parasites can be prevented
by removing breeding sites of the
parasite,
• planting of native species that are
naturally more resistant to pests
native
• using biocontrol agents

12. May 26, 2014 12
1.What are pesticides?
2.The fate of pesticide
3.Effect and alternative approaches
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA
Pesticides are not the only cause responsible for ecological
damage, but they are certainly one of the more serious causes.
This kind of danger has long been ignored, until the reported
fears have become tragic realities.

13. May 26, 2014 13
THE FATE OF PESTICIDES IN THE ENVIRONMENT
DI FRANCESCA DI NICOLA