Lecture 2

Question 1

What can you define classes of contaminants by?

Answer 1

• chemistry
• level of concern
• mode of action
• novelty

Question 2

What does POP stand for?

Answer 2

persistent organic pollutants

Question 3

What are the dirty dozen POPs?

Answer 3

• PCBs
• PCDD and PCDF
• “-drins”
• Chlordane
• DDT
• Heptachlor
• Hexachlorobenzene
• Mirex
• Toxaphene

Question 4

What are the uses of PCB?

Answer 4

coolant/lubricant in transformers

Question 5

What are the uses of PCDD and PCDF?

Answer 5

industrial by-product

Question 6

What are the uses of “-drins”?

Answer 6

organichlorine insecticides

Question 7

What are the uses of chlordane?

Answer 7

agricultural pesticides

Question 8

What are the uses of DDT?

Answer 8

anti-malarial pesticides

Question 9

What are the uses of heptachlor?

Answer 9

insecticides

Question 10

What are the uses of hexachlorobenzene?

Answer 10

pesticide, industrial by-product

Question 11

What are the uses of mirex?

Answer 11

insectice, flame retardant

Question 12

What are the uses of toxaphene?

Answer 12

insecticide

Question 13

What kind of chemicals should we worry about?

Answer 13

• persist in env
• resistant to metabolism
• bioaccumulate and biomagnify
• highly toxic
• PBT chemical = persistent, bioaccumulative, toxic

Question 14

How can you differentiate organic pollutants?

Answer 14

• contain C and >1 C-H covalent bond

- C-H = low polarity, low water solubility

Question 15

What are PAHs?

Answer 15

• Polycyclic Aromatic Hydrocarbons

Question 16

How can you differentiate PAHs?

Answer 16

• 2or + fused benzene rings

Question 17

Characteristics of PAHs?

Answer 17

• persistent
• natural and anthropogenic sources
• env significant PAHs range from 2 to 7 rings

Question 18

What are sources of PAHs?

Answer 18

• pyrogenic
• petrogenic
• natural
• anthropogenic

Question 19

How to differentiate pyrogenic PAHs?

Answer 19

• high T combustion
• unsubstituted
• high molecular weight

Question 20

How to differentiate petrogenic PAHs?

Answer 20

• petroleum

- higher % alkylated PAHs

Question 21

How to differentiate natural PAHs?

Answer 21

• oil seeps
• forest/grass fires
• volcanoes
• wood and animal decay

Question 22

How to differentiate anthropogenic PAHs?

Answer 22

• oil spill, leaks
• burning fossil fuels
• cigarettes

Question 23

What are the two categories of PAHs?

Answer 23

1. low molecular weight -LMW (2-3rings)

2. high molecular weight - HMW (>3 rings)

Question 24

How to differentiate LMW PAHs?

Answer 24

• water soluble
• not bioaccumulate
• acutely toxic

Question 25

How to differentiate HMW PAHs?

Answer 25

- hydrophobic - resistant to oxidation, reduction, vaporization - accumulate in sediments and organism - carcinogens

Question 26

What are the effects of PAHs?

Answer 26

- metabolize to more toxic derivatives - cause death - impair immune system - mammals - impair reproduction, reduce growth and dev most (not mammals) - alter behaviour and cause blood disorders (except plants)

Question 27

What are HAHs?

Answer 27

halogenated aromatic hydrocabons

Question 28

How to differentiate HAHs?

Answer 28

-many congeners

Question 29

What are the effect of HAHs?

Answer 29

similar to PAHs - dev abnormalities - carcinogenic - endocrine disruption - immune effect - very potent

Question 30

What are the sources of HAHs?

Answer 30

- PCBs | - Dioxin, Furans

Question 31

What are the sources of PCBs?

Answer 31

- manufactured compounds - dielectric fluids - monsanto

Question 32

What is the environmental fate of PCBs?

Answer 32

- persistent - trasport -> absorb particles - accumulate

Question 33

How many congeners do PCBs have?

Answer 33

209

Question 34

How to recognize Dioxins and Furans?

Answer 34

``` Dioxin = PCDD Furan = PCDF ```

Question 35

How many congeners do PCDD have?

Answer 35

75

Question 36

How many congeners do PCDF have?

Answer 36

135

Question 37

What are DLCs?

Answer 37

dioxin like compounds subset of HAHs dioxins, furans and non-ortho substituted PCBs very potent toxicant that exert toxicity through AHR pathways

Question 38

What are non-ortho substituted PCBs?

Answer 38

ortho-substituted PCB that dont bind to AHR

Question 39

Briefly describe the AHR pathway:

Answer 39

1. contaminant binds to AHR 2. induce expression of metabolic enzymes - CYP1A 3. CYP1A metabolizes contaminants

Question 40

Do all DLC bind to AHR path?

Answer 40

Yeas and they activate it

Question 41

Can DLC metabolize CYP1A

Answer 41

not very well

Question 42

What are organic pesticides?

Answer 42

chemicals used to kill pests

Question 43

What are the categories of pesticides?

Answer 43

- organochlorines - DDT, chlordane - organophosphates - monocrotophos, chlorpyrifos - noenicitinoids - imidacloprid

Question 44

Defining aspects of organochlorines?

Answer 44

- persistent, biomagnify

Question 45

Defining aspects of organophosphates?

Answer 45

- inhibit acetylcholinesterase (neurotransmiter) | - extremely toxic to birds at low doses

Question 46

Defining aspects of noenicitinoids?

Answer 46

-neuroactive insecticide

Question 47

How can we differentiate Metals?

Answer 47

- naturally occuring - not created nor destroyed - human act alter

Question 48

What are essential metals?

Answer 48

iron, zinc, copper, manganese, chromium, molybdenum, selenium

Question 49

What are non-essential metals?

Answer 49

cadmium, lead, mercury

Question 50

Define emerging contaminants:

Answer 50

chemicals that being manufactured for first time, not historically been considered as contaminant but now are

Question 51

Are emerging chemicals rapidly increasing?

Answer 51

YES