1April 13, 2023FRANCESCA DI NICOLA

The fate of pesticides in the environment

PESTICIDE

Corso di Laurea Magistrale in Valutazione d’Impatto e Certificazione Ambientale

2April 13, 2023THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

1.What are pesticides?

2.What happens to a pesticide after use?

3.Effect and alternative approaches

3April 13, 2023

1. WHAT IS PESTIC IDE

Pesticides are chemicals or biological agents used to:

CONTROL

REPEL

ATTRACT

KILL

PESTS

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 ENVIRONMENTDI FRANCESCA DI NICOLA

4April 13, 2023

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

2. FATE OF PESTIC IDES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

5April 13, 2023

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.

2. FATE OF PESTIC IDES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

W

OOW a

aK

6April 13, 2023

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.

2. FATE OF PESTIC IDES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

7April 13, 2023

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.

2. FATE OF PESTIC IDES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

8April 13, 2023

The fate of a pesticide applied to soil depends on:

persistence and solubility.

2. FATE OF PESTIC IDES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

9April 13, 2023

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.

2. FATE OF PESTIC IDES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

10April 13, 2023

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

3. EFFECT AND ALTERNATIVE APPROACHES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI FRANCESCA DI NICOLA

11April 13, 2023

Many alternatives are available to reduce the effects of pesticides on the environment. There are a variety of alternative pesticides, for example:

3. EFFECT AND ALTERNATIVE APPROACHES

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI 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

April 13, 2023 12

1.What are pesticides?

2.The fate of pesticide

3.Effect and alternative approaches

THE FATE OF PESTICIDES IN THE ENVIRONMENTDI 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.

13April 13, 2023

Would You ever eat a poisoned apple?

Thank You Thank You Thank You THE FATE OF PESTICIDES IN THE ENVIRONMENT

DI FRANCESCA DI NICOLA