Toxicology Flashcards
1
Q
toxicology
A
the study of the effects of chemicals on living organisms
2
Q
no amount of alcohol is safe to drink
A
25, 000 people drinking 1 drink a day- will be 1 extra alcohol related health problem. if 2 drinks- 15 more such problems
3
Q
society problem alcohol
A
individually not a huge risk- if you look at any large pop= actually translates into a lot of cases= this is when it becomes a real problem
4
Q
ischaemic heart disease
A
heart not getting enough blood- consuming small amount of alcohol actually reduces the risk of it/ however there is an increase risk cancer + other diseases- better no alcohol
5
Q
tap water contains
A
trihalomethanes- spring water has a possibility of bisphenol A (BPA) being leached into it = this is an endocrine disruptor
6
Q
anti perspirant has parabens
A
linked to endocrine disruptors
7
Q
chemicals found in air/shower when showering
A
108 chemicals
8
Q
nail polish has a plasticizer called dibutyl phtalate
A
hormone disruptor- comes from studies done on rodents
9
Q
rubber in balloons has nitrosamines
A
carcinogen
10
Q
3 parts per billion of antimony in
A
plastic water bottles
11
Q
detect presence of chemicals does not mean doing anything
A
all about the dosage/ amount of that particular chemical
12
Q
Acceptable Daily intake (ADI)
A
6 parts per billion= we find in plastic water bottles is bellow the ADO
13
Q
need test animals- no observed adverse effect level (NOAEL)
A
rodent pop start giving substance testing- increasing amounts until find a change- then decrease the amount to max of what does not cause any change then divide this number by 100 = ADI
14
Q
Risk
A
in a specific situation, what is the harm? can change
15
Q
hazard
A
cannot change
16
Q
risk vs hazard
A
ex: bear can take off a human head= very hazardous- if bear in zoo= lower risk of happening- if in wild= risk increased
17
Q
Risk =
A
hazard X exposure X vulnerability
18
Q
Chemicals are not to be feared or worshipped-
A
they are to be understood!
19
Q
everything in the world is made up of
A
chemicals
- building blocks of all matter
- 134 known substances- 99.9% naturally occurring
20
Q
-because something is natural does not mean it is safe
A
- socrate was forced to drink the juice of the hemlock plant- contains coniine
- ricin comes from the castor oil plant
- dart frog
21
Q
synthetic does not mean dangerous
A
aspirin is synthetically developed- has an anticoagulant effect= again, dosage is important
22
Q
human body
A
complex and contains many chemicals
23
Q
the smell of coffee contains
A
1000 different compounds
-many are known carcinogens
24
Q
carcinogen
A
substance that has the ability to produce cancer (hazard)- coffee is not carcinogenic- we would know bc so many people drink it
-dont cause cancer bc their dose is too low + body had properties to rid us of toxins
(caffeic acid, benzene, styrene, formaldehyde, furfural, acrylamide)
25
Three tree poison
monkey dies after jumping 3 diff trees- sir walter raleigh
26
urari
toxin= he to whom it comes, falls (name comes from natives)
| -extracted from wine jungle
27
today urari is called curare
charles waterton 1812= curare in the right dose could cause muscle relaxation without death
28
claude bernard
discovered curare blocked nerve impulses from the brain to muscles
-because contains tubocurarine
29
used in surgery to paralyze muscles
curare- first time in mtl by dr harrold griffith
30
Dr Harrold Griffith
first physician use currare to relax the muscle of a patient undergoing an appendectomy 1942
-today we have derivatives developed which are safer to use
31
curare =
poison + drug= all about dosage!!!
32
sulfanilamide
first drug effective against bacteria causes strep throat 1937
-was pill but uSA solution form- what dissolve in? (doesnt dissolve in water)
33
Harold Watkins
dissolve sulfanilamide in diethylene glycol
| - only testing was sticking his finger in and taste sweet= kids will like it
34
sulfanilamide scandal
patients took medication for bacterial infection= excruciating abdominal pain, vomited, blind, dies..
Autopsies kidney and liver failure= watkins took solution to prove.. was not safe!- suicide
-FDA inspectors- 107 dead- 260 permanent disabilities
-234 of 240 gallons recovered (had been manufactured)
35
june 15th 1938
president roosevelt signed into law the federal food, drug, cosmetic act- states companies ow had to prive their product was safe
36
hormesis
biological phenomenon whereby a beneficial effect results from exposure to low doses of an agent that is otherwise toxic at higher doses! EX: sun low= vit D- high= burns + skin cancer
37
Risk =
toxicity X exposure
38
lima beans contain
cyanide- not enough in it to cause toxic effects
| -lethal dose of cyanide 10,000 mcg
39
pufferfish toxic
puff up + release spikes have tetrodotoxin= poison enemies
- people eat them
- people cook intense training to not kill people eating them
- lethal dose 10.00 mcg
40
most toxic substance is produces by clostridium botulinum bacteria
produces botulin= found inside of a cold cut sausage- lethal dose= 0.03 mcg
-cases bottled garlic has developed botulin (rare)
41
botulinum in medicine
to paralyze muscles and stop tremors
- botox to paralyze muscles which reduces wrinkles
- botox may help ease headaches in some cases
- sometimes used to treat chronic anal fissures
42
difficulties
type of exposure/ whether through air, touching, etc.
43
biochemical individuality
people react to substances in different ways = everyone has diff immune syst= need to have built-in safety factors to combat this
44
acute and chronic effects
acute effects easy to investigate
45
teratogenic effetcs
happens when a pregnant woman is exposed to some substances that has an effect on the embryo
46
diethylstilbestrol (DES) - (teratogenic effects)
thought this would help women suffer miscarriages- did not + had neg effects
47
toxin recognition
-animal testing- not same as humans- need to think of the effect it actually has on humans + diff animals may experience something differently
48
psychological factors
placebo effect- believe something will be effective- it may actually have positive effects
49
Dr Harvey W. Wiley
chief of bureau of chemistry did not agree there were no laws for food supply, no study on conservation
50
1903 dr harvey
recruits the poison squad- would eat meals that were tainted with chemicals that wiley though were harmful
Ex: borax, salicylic acid, sodium benzoate, formaldehyde, copper sulfate (all preservatives)
51
poison squad
2 groups= 1 dosing/ other no
- dosage ranged from 0.5 to 4 grams daily
- all meals eaten at hygienic table- chemicals consumed in gelatin capsules- urine and feces were collected/mesured
- found these caused nausea, vomitting, stomach aches.
- stopped eating- felt better
- no long term damage
- led to Pure Food and Drug Act of 1906
52
pure food and drug act 1906
which removed harmful and misrepresented foods and drugs from the market and regulated manufacture and sale of drugs and food involved in interstate trate
53
natural detox system composed liver + kidneys
- organs filter out many toxins
- phase 1 enzymes= make the substance more water soluble (washed out through urine)
- phase 2 enzymes attach another molecule to the toxin; chemically change the toxin to help it be excreted
54
Cytochrome p-450 family of enzymes
most importante phase 1 enzymes
55
detox enzymes can be induced
- green tea can stimulate phase 2 enzyme glucuronyl transferase
- brocoli releases a compound called sulforaphane when chewed on= even more so w broc sprouts
- garlic stimulates glutathione-s-transferase
56
enzyme stimulation is not always beneficial
saint johns wort (flower)= marketed as an anti-depressant- consumed stimulates production of cytochrome enzymes because body tries to get rid of it
57
cyclosporine
drug used to suppress the immune system so that body wont reject an organ transplant
58
st johns wort stimulates
production of cytochrome p-450- combined with the immune system suppressant will rid the body of cyclosporine thus causing body reject the organ
*cannot combine it with drugs that are synthesized in the same way
59
acetaminophen
metabolized in the liver- where enzymes are produced that will take care of it
60
acetaminophen not very water soluble
enzymes try to make it more so by combining it with glucuronyl transferase
-BUT if take too much wont be enough glucuronyl transferase- so cytochrome p-450 (phase 1) stimulated leads reactive intermediate (N-acetyl-p-benzoquinone imine)= causes liver damage!!!
61
acetaminophen + alcohol
leads to production of cytochrome p-450
62
glutathione-S-transferase
used to combat the liver damage to reduce the toxicity (need gluthione to do this)
-important as a detoxifying agent but cannot be absorbed intact
63
high cystein whey protein
sold as a product to increase the immune system
64
supplements can present a problem-
over last decade liver injury from herbal supplements have tripled
65
DryElite powder had a drug in it that was not listed-
slap on the hand- replaced it with "natural product" (bael fruit) but still had bad effects- was taken off market
66
in hemoglobin there is
heme- which holds the iron
67
red blood cells dont have a very long lifetime-
body needs to use enzymes to get rid of the leftover heme,
| -glucu creates bilirubin which combines with it to make it more water-soluble- so it can be excreted
68
babies get jaundice bc
have insufficient glucuronyl transferase- can combat this by using a blue light which actually has enough energy via "bili" lights
69
allergies- seldane
antihistamine which did not make you drowsy
70
enzyme used to create the active metabolite which has the antihistamine effect
cytochrome
71
anti-fungal medication ketoconazole + cytochrome
interacted= blocks it- dont get the conversion into the active metabolite- caused heart attacks
72
to fix this- the active metabolite
synthesized without going through these steps- this is what is now known as allegra
73
felodipine
alcohol had no effect
- grape juice yes bc felodipine is is synth by cytochrome p-450 / grape-juice inhibits cytochrome p-450 so the dosage was no longer right and there was too much of the felodipine
- MUHC and other hospitals chose to eliminate grape juice
74
active ingredient in grape juice
group called furanocoumarins
75
depression- monoaminoxidase inhibitor (MAOI)
- norepinephrine, serotonin, dopamine
- people who took these + eat cheese= developing high blood pressure (hypertension) bc cheese contains tyramine- usually broken down by the body- MAOI inhibited the MAO that was breaking down the tyramine- which was leading to these issues
76
rubber ducks cut open- bacteria found inside
- not actually rubber- polyvinyl-chloride (PVC) ducks
- 19 ducks bathed every other day= all toys developed biofilms- no more hole in rubber ducks
- not harmful
77
dioxin
most toxic man made chemical
| -does not occur in nature; refers to group of compounds
78
most notorious dioxin compound
tetrachlorodibenzodioxin (TCDD)
| -most potent carcinogen ever tested on animals
79
charles darwin
naturalist
-first person to suggest plants grew bc they generated certain hormones that allowed them to- died (1880s) before first hormone was isolate (1928)
80
first hormone isolate
1928 Auxin
81
scientists came up structures modified versions of Auxin to see effects
- 2,4-dichlorophenoxyacetic acid (2,4-D)
- 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)
- these structures caused such rapid growth that the plants didnt have enough nutrients to keep up
82
agent orange
called this bc of the barrel- contaminated with TCDD-
83
victor yuschenko
poisoned w dioxin- had chloride acne and everyone thought he was going to die.. but He still alive
84
love canal
lot of chemical spills in this area- dioxin was release so people thought that it was causing others to die- no one died but there were respiratory issues- there was also a large deal of other chemicals let out into the area
-plp dont know dioxin actually involved- bc all other chems
85
effects from chem exposure (love canal)
- high white blood cell counts
- chromosome damage
- miscarriages
- learning problems
- eye irritation
- abdominal pain
86
unreasonable dioxin worries
can release dioxin by microwaving containers- not true!!! made from polyethylene or polypropylene which dont contain chloride- therefore dioxin cannot be created!
87
just bc 2 things are associated does not mean they are the
cause!
| "after it, therefore bc of it"
