Unit 4 Ecotoxicity

Question 1

What is toxicology?

Answer 1

The study of poisons/toxins and their effects on organisms

Question 2

What is ecotoxicology?

Answer 2

The study of toxicology including environmental factors

Question 3

What is the most common use of toxins for ecotoxical studies?

Answer 3

Development testing and use of pesticides

Question 4

What is a persistent factor?

Answer 4

How long it takes for the chemical to break down. Shorter better

Question 5

What’s the difference between fat solubility and water solubility?

Answer 5

Water soluble substances can be excreted from your body and can be easily entered into water systems where as fat soluble substances absorb into fatty substances and can build up over time

Question 6

What is biomaccumulation/biomagnification?

Answer 6

A little bit of toxins everyday until excessive.

Exponential increase

Question 7

What is a antagonistic effect?

Answer 7

Two or more substances cancel each other out (less toxicity)

Question 8

What is a synergistic effect?

Answer 8

When 2 or more toxins have a pronounced effect.

Question 9

What is the percentage of intended pathway to actual pathway

Answer 9

2% reaches where we want it to go and 98% does not

Question 10

What is the grasshopper effect?

Answer 10

When toxins are moved to the piles through wind currants by “jumping” up or down

Question 11

What is genetic based tolerance?

Answer 11

When an organism mutates and becomes tolerant to the toxin

Question 12

How do we manage toxins?

Answer 12

Conduct risk assessments that describe quantity and hazards and evaluate the harm.

Question 13

What is risk

Answer 13

Probability that an activity or exposure will be harmful.

Question 14

What are the factors in evaluation of risk?

Answer 14

• hazard identification
• dose response assessment
• exposure assessment
• risk characterization

Question 15

What is LD50 and ED 50

Answer 15

Lethal dose that kill 50% of the population and

Effective dose that causes specific responses to 59% of the population.

Question 16

What can a dose response curve give us?

Answer 16

Can help identify LD50 ED50 and the threshold level

Question 17

What is hazard quotient?

Answer 17

It is the estimate exposure and toxicity that uses the highest amount of environmental concentration and then observing the most sensitive organism in that environment

Question 18

What is EEC

Answer 18

Exposure consintration

Question 19

What is TBC

Answer 19

Effect concentration

Question 20

What is the formula and ration for HQ

Answer 20

EEC/TBC=HQ

HQ>1 toxic effects
HQ<1no toxic effects

Question 21

What are persistent organic pollutants (POPs)

Answer 21

Synthetic compounds used in manufacturing, insulators, cooling

Question 22

Who is Rachel Carson?

Answer 22

Author of silent spring, grandmother of environmental science, raised public awareness about ddt

Question 23

What is the Stockholm convention?

Answer 23

An organization that includes POPs management and cleaning up the dirty dozen

Question 24

What is the most toxic form of mercury? Why?

Answer 24

Methylmurcury, organic- eaten by bacteria and entered into the food chain (fat soluble)

Question 25

How is mercury released by humans?

Answer 25

Burning coal, smelting etc

Question 26

How has the Canada mercury emissions changed since 1990?

Answer 26

It is 87% lower and 95% comes from the USA

Question 27

What is substance agriculture?

Answer 27

Small production, just for the family

Question 28

What is a slash and burn approach to agriculture?

Answer 28

Cutting then burning a forested area to use ash as fertilizer, then abandon to let the forest grow back, but the forest doesn't grow back because all the nutrients are gone

Question 29

What is industrialized agriculture?

Answer 29

Crop yields are enhanced through the use of large machines and large inputs of resources (cash crops)

Question 30

When/what was the green revolution?

Answer 30

1940-1960 It was the introduction of high trials crops, chemical fertilizers, synthetic pesticides, multiple cropping, and lower production costs

Question 31

What were the problems with the green revolution?

Answer 31

Pollution and fanatical investment for farmers and less developed land

Question 32

What contributes to soil conservation?

Answer 32

- attributes that make the soils clump and crumble - water retention capacity - soil community contributing to organic layer - Clay sand and salt vary in size to let water in

Question 33

What are the 4 major components of soil and how much of each for ideal soil

Answer 33

5% organic material 45%minerals 25% water 25%air

Question 34

What is the cation exchange capacity (CEC)

Answer 34

It is when clay (negatively charged) holds cations/minerals in place for plants to absorb

Question 35

What are the layers of soil that has not been plowed ?

Answer 35

``` O horizon (organic) A horizon (topsoil) B horizon (subsoil) C horizon (weathered rocks/water) D horizon (parent material) ```