Pesticides diseases and DDT 1 What are two

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Pesticides, diseases, and DDT 1) What are two ways chemicals get into the environment?

Pesticides, diseases, and DDT 1) What are two ways chemicals get into the environment? b) What is the difference between persistent and non-persistent? 2) What is the difference between pesticides, herbicides, and insecticides? 3) What does ingestion and absorption mean? 4) What is one pro and one con for DDT?

Looking at this photo: How are chemicals getting into our water system?

Looking at this photo: How are chemicals getting into our water system?

Types of wastes Non- persistent: Will break down by natural ways in the environment.

Types of wastes Non- persistent: Will break down by natural ways in the environment. Ex) sewage Persistent: Will not break down in the environment very easily. Ex) DDT, mercury

Pesticides Pesticide: Herbicides Insecticides What they control plants insects Example pests Weeds Mosquitoes Example

Pesticides Pesticide: Herbicides Insecticides What they control plants insects Example pests Weeds Mosquitoes Example pesticides Roundup DDT

DDT • Dichlorodiphenyltrichloroethane … We’ll just call it DDT

DDT • Dichlorodiphenyltrichloroethane … We’ll just call it DDT

DDT - Used in WWII to exterminate lice. PRO

DDT - Used in WWII to exterminate lice. PRO

DDT: Lice/Typhus - The lice carried the disease typhus, which cause devastating effects, sometimes

DDT: Lice/Typhus - The lice carried the disease typhus, which cause devastating effects, sometimes even death, on the soldiers. PRO

DDT: Mosquitoes/ malaria - Mosquitoes carry malaria, which causes your red blood cells to

DDT: Mosquitoes/ malaria - Mosquitoes carry malaria, which causes your red blood cells to burst open. This means they can no longer carry oxygen. PRO

Pros of DDT: - In African countries, the use of DDT caused a drop

Pros of DDT: - In African countries, the use of DDT caused a drop of malaria from 70% to 5% in just 6 years. PRO

How DDT gets into organisms Ingestion: eat it. Digestive system Inhalation: Breath it in.

How DDT gets into organisms Ingestion: eat it. Digestive system Inhalation: Breath it in. Respiratory system Absorption: absorbed through the skin. Circulatory system

Evidence against DDT -It has a half-life of 12 years. Meaning it does not

Evidence against DDT -It has a half-life of 12 years. Meaning it does not leave the environment for many generations. - It is fat-soluble meaning it dissolves into fat stores and stays in organisms for decades. CON

Peregrine Falcon -Stops the flow of calcium from mother to eggs. This meant the

Peregrine Falcon -Stops the flow of calcium from mother to eggs. This meant the eggs were not at thick and strong as they should be. - These brittle eggs would break, resulting in less falcons making it to adulthood. - These birds almost went extinct CON

DDT: collects in the food chain - As DDT moves up the food chain.

DDT: collects in the food chain - As DDT moves up the food chain. More of it collects in the fat stores of animals.

Biomagnification - Build up of substances, such as pesticides, in an organism. - It

Biomagnification - Build up of substances, such as pesticides, in an organism. - It is being absorbed faster than the substance is lost.

DDT debate • Life-saving or life-threatening?

DDT debate • Life-saving or life-threatening?

Pesticides, diseases, and DDT 1) What are two ways chemicals get into the environment?

Pesticides, diseases, and DDT 1) What are two ways chemicals get into the environment? b) What is the difference between persistent and non-persistent? 2) What is the difference between pesticides, herbicides, and insecticides? 3) What does ingestion and absorption mean? 4) What is one pro and one con for DDT?