Midterm-Final Flashcards
(375 cards)
1
Q
____ was used as a medicine for skin disease that resulted in many people dying in francce
A
Salinon (triethyltin)
2
Q
Canned foods are easily contaminated by tin - how does this happen?
A
Usually through seams or the can itself.
3
Q
What compounds can cause more leaching of tin into canned food?
A
Nitrates, caramel, sulphur compounds.
4
Q
How can one avoid tin leaching into cans?
A
take food out immediately after opening can
5
Q
Where does Vanadium come from?
A
Fossil fuels, mining, and oily foods
6
Q
Do we need Vanadium?
A
It seems to be essential in nutrition (perhaps in reducing the need for molybdenum by intestinal symbionts)
7
Q
Where does Vanadium accumulate and what does it do in the body?
A
Accumulates in fat. Accelerates bone mineralization
8
Q
What products contain vanadium?
A
Batteries, surgical tools, plating, saws
9
Q
What happens during vanadium poisoning?
A
GI problems, headache, green tongue, metallic taste in mouth
10
Q
What vitamin is used as an antitode for vanadium poisoning?
A
Vitamin C
11
Q
Where is Zinc found?
A
Fossil fuels, mines, smelters, galvanized iron, plumbing fixtures, tanks, zinc-carbon batteries
12
Q
What are the uses of Zinc in the body?
A
Needed for normal insulin secretion, inhibits replication of rhinoviruses, essential in nutrition
13
Q
What products typically contain zinc?
A
bike chains, basically anything galvanized, supplements
14
Q
Zinc _____ is a powerful poison used in many places as a rodenticide
A
Zinc phosphide
15
Q
Vitamin ___ enhances Zinc absorption
A
Vitamin D
16
Q
Where does Zinc accumulate in the body
A
Muscles, bone, prostate. Higher in healing tissues (wounds/fractures)
17
Q
When is the Zinc body burden highest?
A
Around age 45
18
Q
What occurs from Zinc deficiency?
A
Smells are super weird, poor appetite,
19
Q
Zinc deficiency is most common in what type of people?
A
Alcoholics
20
Q
The Canadian drinking water guideline for zinc is ____micrograms/L
A
___?
21
Q
few more zinc things like symptoms
A
dssd
22
Q
What are radionuclides?
A
have both chemical and radiation hazard (radioactive elements)
23
Q
What are some sources of radionuclides?
A
Disintegrate from other elements, come naturaly from radioactive minerals in rocks, mines, reactors, hospital/research facility waste, storage of fuel rods, satellite crashes, fallout from nuclear weapons testing and reactor disasters
24
Q
What is the difference between particle and non particle radiation?
A
Alpha and Beta radiation are legitimate particles (Can’t penetrate as much) whereas gamma radiation and x-rays can penetrate
25
How does half life differ between the environment and in the body?
Much lower half life in body
26
What is one place in MB where the water is too radioactive to drink?
Lac Du Bonnet
27
Where does Uranium accumulate in the body? What about food?
Deposited in bone. Bioaccumulates in crops (esp. in Okanagan valley)
28
The guideline for uranium is ___ micrograms/L
20
29
more uranium
yup
30
Strontium-___ is radioactive. Where does it usually come from
Strontium-90. Comes from mostly nuclear weapons testing
31
Describe the interactions between strontium and cows
GRass, vegetables eaten by cows ends up in milk (ends up incorporated instead of calcium), bioconcentrates in milk
32
Where is Cesium-137 most common
northern MB waters, baltic sea.
33
What is Radon gas?
radioactive gas produced by decay of uranium in rocks/soil. Dissolves in groundwater
34
____ is the second leading cause of lung cancer in canada
Radon gas
35
Why is radon a major health concern in MB?
Very common, has no smell or taste. Causes lung cancer, but seeps into basements through cracks/seems in foundation. .5 of MB houses have radon levels higher than what is considered safe
36
What is the biggest risk for radon gas exposure through water in MB?
owning a well. Aerating the water displaces radon gas which causes it to accumulate in the basement
37
Why does sealing cracks in houses increase radon gas exposure?
it can't dissipate out of basemen
38
how are cigarettes and radon synergistic?
Radon gas + cigarettes increase lung cancer risk 10X
39
most of radon exposure is through ____
inhalation
40
How did the fukushima reactor affect canadians?
Most fish caught in BC is now contaminated with radioactive materials
41
Organic parameters contain at least the elements ___ and ___
C and H
42
Surface water generally contains (more/less) organic matter than groundwater
more
43
How are organic molecules affected by municipal water treatment?
They are not
44
How do synthetic organics degrade?
They basically don't.
45
What are some awful contaminants in laundry detergent?
Ethylene glycol, benzene, germicides, anticaking agents, antideposition agents, antidusting agents, perfumes, bleach, chelators, endocrine disruptors, sometimes proteolytic enzymes
46
What are surfactants?
Function to disperse nonpolar substances in water
47
Where are surfactants found?
Detergents, cleaners, industrial solvents, pesticides
48
Alkylbenzene sulphonates differ from alkylbenzene sulphates in what way?
sulphonates -
| sulphates -
49
Almost anything with a benzene ring is _____
very toxic
50
surfactants cause what issues in humans?
Easily absorbed, cause diarrhea, interfere with GI ability to digest foods (inhibits digestive enzymes)
51
Nonylphenol ethoxylate surfactants act as ______ disruptors. What problems can this cause?
endocrine disruptors, can cause early puberty in women
52
---- estrogenic??
kkk
53
Where is benzene found?
gasoline, lighter fluid, as a solvent, used to manufacture: pesticides, detergents, drugs, air fresheners
54
Benzene is volatile - what does this mean?
Converts to vapour easily - low boiling point (esp a problem when distilling water)
55
Benzene can persists for a long time in ___ water
groundwater, anaerobic conditions
56
How is benzene taken into the body?
Inhalation (cigarette smoke), or absorption through skin
57
What does benzene do in the body?
damages bone marrow, WBC, RBC, platelets (pancytopemia), depresses B and T cells, damages liver, causes cancer, accumulates in fat
58
Typically organics are more toxic in ___ (males/females) than ___. Why?
females than males, because women typically have more fat and these things accumulate in fat
59
_____ are a fruit containing benzoic acid
cranberries
60
What is one way to avoid benzene in your car?
Benzene is emitted by most car fixtures - so before you turn on AC, it is important to open car windows and allow benzene to leave
61
Carcinogenecity and bioconcentration of chlorinated benzenes increases with number of ____
chlorine atoms
62
What are phenolic compounds?
Naturally arising compounds with benzene ring as fundamental structural unit. Some are super large with many rings bound together
63
Phenolic compounds come from where?
Mostly pulp/paper mills, pesticide/drug manufacturing, plastics factories
64
Can we taste phenolic compounds?
yes, at 0.3mg/L
65
What happens when phenolic compounds go through a water treatment plant?
Produces worse carcinogens
66
What are acute symptoms of phenolic compounds?
abdominal pain, diarrhea, vomiting
67
What are chronic symptoms of phenolic compuonds?
liver/kidney damage, CNS damage, slow growth, fetotoxic, causes leukemia and lymphoma
68
MEthylene chloride is found in what?>
spray paints, adhesives, paint/glue removers, cleaning fluids, wood stains, varnishes, water repellents, cigarettes, many hygiene/cosmetics
69
Methylene chloride is metabilized in the body to ___
carbon monoxide
70
What activities increase absorption of methylene chloride?
being fat, excercising
71
How does CO affect the brain?
binds to hemoglobin PERMANENTLY
72
what are symptoms of methylene chloride intake?
CNS damage, psychotic symptoms, cancer
73
Where does ethylene glycol come from?
antifreeze, solvent. Disposal of used antifreeze down drain, winterizing water lines in cottages, boats, pools
74
What does antifreeze taste like?
sweet
75
A _ __ of antifreeze is lethal to a cat, a _ __ of antifreeze is lethal to a dog
teaspoon, tablespoon
76
About _____ mL of antifreeze is lethal to humans within 72 hours
100mL
77
propylene glycol is a toxic additive in many foods, drugs, and other products. name some
makeup, shampoo, deodorant, hair detangler, styling gel, bubble bath, conditioner, wallpaper stripper, de-icer
78
what are pthalate esters primarily used in?
Plastic products - keep plastic flexible
79
pthalate esters are found in what consumer products?
Pesticides, dyes, lubricants, nail polish, "fragrance", "parfum", hygiene, air fresheners, IV fluid, medical tubing/gloves
80
How do pthalates relate to food?
Found in aluminum foil, plastic wraps, plastic bottles such as condiment containers
81
How do pthalates affect humans?
affect mitchondria, implicated as hormone disruptor in early female puberty, cancer, internal bleeding, low sperm count/male reproductive disorders, allergic response.
82
Why is it that it is recommended to use fabric shower curtains to avoid pthalates?
High temp can aerosolize pthalates
83
How do microwaves relate to pthalate intake?
DO NOT MICROWAVE IN PLASTIC TRAYS, or microwavable popcorn bags
84
How do dioxins vary?
According to number and arrangement of chlorines
85
Where do dioxins come from?
Byproducts from manufacturing chlorinates pesticides, bleached pulp mills, incineration of chlorinated chemicals
86
What occurred when Dow Chemical employees were spreading a compound called "Brushkill"
This compound contained dioxin and people spreading it did not provide proper PPE, and people died of cancer and other illnesses
87
_____ is a U.S. military toxin used in WWII containing dioxin
Agent Orange
88
most of our exposure to dioxins come from ____
beef, fish, seafood, eggs
89
the half life in body fat of dioxins is _____
7.1 years
90
What occurs from dioxin poisoning?
hair loss, liver/nerve damage, male fetus more susceptible, females + children in general more susceptible, can attach to DNA, cause endometriosis.
91
aromatic compounds are what?
compounds containing benzene rings
92
PAHs are what?
polycyclic aromatic hydrocarbons
93
PAHs are found in what
fossil fuels, vaseline, smoking/frying/barbequing, tobacco smoke, paints/coatings, asphalt-lined distribution pipes, sewage effluent, industrial effluent, road leaching
94
PAHs cause what?
asthma, heart problems, low IQ, very high carcinogenic
95
Why is BBQing the biggest average exposure to PAHs?
Char has PAHs, fat dripping into fire produces PAHs
96
Bisphenol-A is abbreviated to....?
BPA
97
Where is BPA found?
polycarbonate plastics, nalgene, shatterproof plastic, food can linings, eyeglass lenses, older baby bottles/nipples, receipt paper, glossy paper, printer ink, high levels in recycled paper
98
BPA can be identified by the recycling symbol #___
#7
99
How does BPA act on the body?
Hormone disruptor, estrogen mimic. Causes the usual reproductive problems, developmental/attention problems, cancer
100
What are PCBs?
Polychlorinated biphenyls
101
Where do PCBs come from?
Electrical transformers, capacitors, old microscope immersion oils, old fireproofing, carbonless copy paper, adhesives, pesticide extenders
102
TRUE OR FALSE: PCBs can be inhaled
true
103
Atmospheric DDT is converted to ___ by UV light
PCB
104
Toxicity of PCBs increases with number of _____s
chlorines on molecule
105
How do PCBs act in the body
mimic estrogen, accumulate in fat, concentrate in breast milk
106
The disease caused by PCB exposure is called ____
Yusho disease
107
What are symptoms of Yusho disease (excessive PCB)
CNS depression, brown pigmentation of skin/nails (looks like freckles), characteristic chemical body odor, cancer
108
Polybrominated flame retardants are very similar to ____s. What is the difference?
PCBs - have bromine atoms instead of chlorine atoms
109
Polybrominated flame retardants are found in what?
Water/food (contaminated), used as flame retardant, dust - furniture, electronics, airplanes, any sealed (energy efficient) building,
110
Polybrominated flame retardants are otherwise known as ____
PBDEs (polybrominated diphenyl ethers)
111
TRUE OR FALSE: wild salmon have higher flame retardant levels than farmed salmon
FALSE
112
PBDEs/polybrominated flame retardants cause what symptoms?
oh boy
113
PFCs are otherwise known as _____
perfluorinated compounds
114
Where are PFCs found?
teflon, food container liners, none-stick materials, stain/water repellent treatments, toaster ovens, space heaters, heat lamp
115
The primary manufacturer of PFCs is ____
Dupont
116
PFCs have been implicated in the death of what animal. How?
Birds - extremely toxic to birds. "Teflon toxicosis", results in millions of bird deaths in the vicinity of teflon factories.
117
What are effects of PFCs in humans?
Birth defects (ex. cleft palate), developmental/hormone problems.
118
Why is the use of PFCs in cooking a huge deal?
More toxic above 400F and most toxic about 680F - people can die from cooking in high heats
119
PFCs are synergistic with ____
cigarette smoke
120
What is a good way to avoid PFCs?
buy "PFOA" free, keep pet birds out of kitchens, phase out teflon cookware
121
What is triclosan?
Antibacterial agent found in many antiseptics such as hand sanitizer, dish soaps, toothpaste, underwear, shower curtains, cutting boards, mouthwash, toyota steering wheels, chopsticks, pillow cases, so many other things that we may not want bacteria on
122
What problems are posed by triclosan?
Breaks down to dioxin.
| promotes antibiotic resistance
123
When are pharmaceuticals a very big problem in drinking water
particularly in communities downstream of another community - not removed from wastewater - no DW guideline
124
What pharmaceuticals are most widely found in the water?
antibiotics, hormones (ex. BC pills), cholesterol pills, painkillers (ex. ibuprofen)
125
_/_ of all GI illnesses in Canada are due to microorganisms in tapwater
1/3
126
Why are pathogens sometimes not found in water?
May be present in water at such low densities they are not detectable. May exist as strains that do not show up in tests. Samples very heterogenous across a water body, a year
127
what is required to screen for giardia or cryptosporidium?
run at least 1000L of water through filter
128
Why are viruses a huge concern in water?
Any human virus that can be excreted will likely be transferred by water. Water treatment/filtration does no help with virus, May remain latent for a long period of time in the body
129
Viruses that most often have long latency periods are ____
oncogenic viruses
130
How many viruses need to be ingested to produce illness?
Dependent on type of various, state of individual
131
If water is dirty, does that mean there are lots of viruses?
No. In fact, viruses are more common in "clean" water
132
What enteric viruses are most common?
Hep A
133
How does one acquire Hep A and what does it do?
Acquired from ice, swimming pools, drinking water? spreads to blood and invades liver.
134
Where are bacteria found in water?
All surface waters contain bacteria, but most are benign
135
What bacterial species causes many musty tastes/odours in water?
Actinomycetes
136
Where do actinomycetes such as streptomyces proliferate?
Anaerobic environments (ex. water reservoirs)
137
What is one substance produced by actinomycetes that makes fish smelly?
Geosmin
138
What are the two most common iron-bacteria genera found in MB?
Gallionella, Sphaerotilus
139
Where are iron bacteria often found in water?
Groundwater with high iron or sometimes in iron pipe distribution systems
140
What do iron bacteria do?
Convert soluble Fe to insoluble ferric hydroxide
141
What does Sphaerotilus do in the water?
Secrets mucilage sheath and creates slime, plugging filters and interfering with water flow
142
Iron bacteria result in what problems in water?
Rusty discoloration of water, odour, iron taste
143
Which sulphate reducing bacterial species is most common in MC?
Thiobacillus
144
Thiobacillus bacteria can produce sulphuric acid - what does this do?
Corrode metal/concrete pipe
145
Desulphovibrio desulphuricans converts sulphur to _____
H2S
146
Pathogenic bacteria in water come from what practices?
sewage, manure, wildlife, pets, landfills, industrial effluents
147
If most pathogenic bacteria cannot proliferate in water, how do they infect humans?
remain viable for an extremely long time
148
Globally, pathogenic bacteria are the ____ greatest killer of children under 2 years old
SINGLE!!
149
obligate anaerobes in our digestive tract outnumber other organisms by ______:1
1000:1
150
What are some general traits of coliform bacteria?
Bacilli, lactose-fermentors (CO2 producers), all aerobic or facultatively anaerobic
151
Total coliform counts are always expressed as ___
MPN - most probable number per 100mL
152
Fecal coliform bacteria come from feces of whom?
Warm blooded animals/birds - indicate that fecal contamination has occurred
153
How often is water sampled for coliforms?
Weekly if above 5000 pop'n, biweekly otherwise
154
max levels for total coliforms is what?
10% of samples, with 10MPN - none must be fecal
155
What is the primary cause of travellers diarrhea/sickness?
different (geographic) people have different strainsof normal flora, and travellers do not have antibodies against them
156
What are some symptoms of E. coli infection?
nausea, diarrhea, dehydration, usually no fever, intestinal epithelium invasion, enterotoxin production,
157
What are the best fixes for e. coli infeciton?
Loperamide hydrochloride, pepto bismol
158
What causes the actual symptoms in Shigella infection?
Enterotoxins - in fact you don't even need to ingest shigella if the toxin is present
159
In what ways are shigella bacteria so hardy?
Can survive in cold water (4 degrees), need less than 10 to infect
160
What are the primary sources of Klebsiella and what are some symptoms?
fecal contam, pulp mills. Symptoms: Endocarditis, UTI, meningitis, respiratory failure
161
What are the primary sources of Yersinia spp?
Natural zoonotic reservoirs (animal defecation), livestock, pets
162
Does chlorination kill Yersinia spp?
No
163
What condition does Yersinia cause? What is the major symptom?
Yersiniosis. Abdominal pain in right lower quadrant of abdomen - sometimes misdiagnosed as appendicitis. High Fe may make people more susceptible.
164
salmonella notes
bbjddbal
165
What is the number one way to avoid salmonella poisoning?
fully cook chicken and eggs
166
What is the primary reason why there are so many untreatable Campylobacter strains?
Because when we developed fluoroquinilones we begged agricultural industries not to use it as a prophylactic but they did it anyway - now many are resistant
167
Where can people acquire legionella pneumophila?
inhalation of aerosols from contaminated water - HOT WATER, spas, jacuzzi
168
What are symptoms of legionnaires' disease?
fever, respiratory infections - 20% mortality
169
Where did people recently develop legionnaires' disease in MB
krevco hottubs - display tubs
170
Where does the bacterium Leptospira interrogans come from? How does infection occur?
Urine of rats, livestock, wildlife. Infection occurs via bathing, washing, swimming, from contact with water especially if you have a cut
171
What are symptoms of Leptospira infection?
Abrupt frontal headache, fever, red eyes, progresses to CNS, kidneys, permanent liver damage
172
Where does Leptospira infection occur?
Mostly eastern europe - doesn't occur here
173
Where can one get Chlamydia trachomatis?
Waterborn rickettsia, infects eye conjuctiva
174
What are the two names for Brucella infection?
Brucellosis, undulant fever
175
Where do we acquire Brucella from in MB?
Cattle, pigs, rabbits
176
What is one of the main problems with TB infection?
Long latency period - very common in Northern FN reserves
177
What factors make one more susceptible to TB infection?
Lymphoma, asthma, alcoholism, some others
178
What is the causative agent of cholera?
Vibrio cholerae
179
How do people infected with cholera often die?
dehydration
180
actively feeding unicellular protozoa are referred to as
trophocytes
181
What are the two main protozoan water parasites
Giardia, Cryptospiridium
182
What is Giardiasis otherwise known as?
Bever fever
183
Where is giardiasis a huge problem?
Russia, Canada, US
184
What kind of waters often contain giardia?
clean looking water
185
What are some zoonotic sources of giardia?
Beavers, muskrats, cats/dogs, sewage
186
How can humans give others Giardia infecitons?
Shitting in lakes, washing diapers in lakes
187
WHat are the symptoms of Giardia infection?
10ish day incubation. Intermittent diarrhea, neausea/loss of appetite. Lasts up to 7 weeks
188
How do Giardia infect humans?
Stick to wall of intestine, cause ulcers and may exposure one to secondary infection
189
What is Giardiasis often misdiagnosed as?
peptic ulcers
190
Where can one acquire salmonella infection in MB?
livestock, pets, contaminated meat, salads
191
How can salmonella bacteria be killed?
boiling water
192
What are sources of Cryptosporidium?
Wild animals, livestock, pets release cysts in water or food
193
What are symptoms of cryptosporidium infection?
diarrhea, abdominal pain, weight loss, fever
194
Who is most affected by cryptosporidium infection?
Babies - may die
195
What is the most famous Cryptosporidium outbreak ever?
1993 Milwaukee
196
Have we had Cryptosporidium outbreaks in Canada?
Yup. ex. dauphin
197
How many cysts are necessary to be infected with Giardia? Cryptosporidium?
G - 1
| C - 10
198
What are the primary differences between Giardia and Cryptosporidium infection
Giardia - cyst double the size, infection lasts longer
199
What treatment methods can be used for Giardia and Cryptosporidium?
Chlorination is not effective for C, but is for G. Biling over 1 min works for both. Filtration using micropore filters works.
200
What are the health risks for exposure to both G and C?
Health status (illness, stress), genetic strain of cysts, number of cysts ingested, what the organisms are ingested with, age/gender
201
How can C and G be treated?
Using drugs that generally cause the same symptoms as the illness itself
202
Entamoeba histolytica is the causative agent of what?
Amebic dysentery
203
What is the primary difference between E. histolytica and E. coli?
Coli has 8+ nuclei, histo has 1-4 nuclei
204
How is E. histolytica spread
domestic dogs/cats
205
What are symptoms of E. histolytica infection?
Damages intestinal epithelium, causes ulcers and bleeding and can enter blood stream, where they find other organs such as the liver, brain.
206
Naegleria gruberi is the causative agent of what?
Amebic meningoencephalitis
207
How does one acquire N. gruberi?
Inhalation of aerosol containing amoeba?
208
Do people die of Naegleria infection?
Yes. Inc period of 4-6 days and they can infect brian and kill you
209
Balantidium coli is what type of organism?
Ciliated protozoan - almost visible by naked eye
210
Where is Balantidium coli found?
Intestines of humans and pigs, spread by drinking/inhaling
211
What are symptoms of Balantidium coli?
Damages/ingests mucosal and submucosa. tissue - intestinal inflammation, diarrhea - may enter bloodstream and invade spinal fluid
212
Is there Balantidium in MB?
yes, from hog barns
213
What are the primary reservoirs for human helminth infection?
Livestock/pets
214
What is the basic nematode life cycle?
Mature worm lays eggs in intestinal mucosa, hatch into larvae. Shed with feces. Penetrate feet or mouth of new host. Enter bloodstream, carried to lungs, break out and migrate to bronchi. swallowed and carried to small intestine. Attach to mucosa and suck blood.tissue cells. Mature into adults. Adult worms live up to 5 years, heavy infection and migration to other organs may lead to death
215
What is the approx waiting period for nematode infection?
4 weeks
216
What are conditions caused by hookworm
Ankylostomiasis, one other?
217
What are symptoms of nematode infection?
Diarrhea, neausea, vomiting, abdominal pain, fever, bouts of coughing, sore throat, weight loss
218
What are nematode infections often misdiagnosed as
peptic ulcer
219
Pinworm is cased by what?
Enterobius vermicularis
220
What is the most common helminth infection in US and Can
Pinworm
221
What is the reservoir host for Enterobius vermicularis?
Humans
222
Dracunculus medinensis is the causative agent of what
Draontiasis/dracunculiasis
223
D. medinensis is otherwise known as what?
Guinea worm
224
What is the intermediate host for Dracunculus medinensis?
Cyclops.
225
What happens in the life cycle of Dracunculus medinensis?
intermediate host is Cyclops, where larvae develop. When water containing Cyclops is ingested, parasite travels to connective tissue and muscles. Male worm dies after mating and female grows to over 1 meter long over a year, pokes through skin and discharges eggs whenever skin comes in contact with water. Lives for 3 weeks then dies
226
How does one remove a Guinea worm?
Grab the worm, wrap it around a stick, and over several weeks you pull a little bit more of it out until the worm is fully removed
227
The whipworms are known as ______
Trichuris trichiura
228
Where do whipworms live in humans?
Attach to mucosa for small intestine
229
What are symptoms of Whipworm infection?
Abdominal pain, diarrhea, weight loss, nausea, bleeding
230
What is the life history of whipworms
Eggs passed in water, larvae can hatch in water and can live for a few weeks if not ingested.
231
What are the two major groups of Ascaris?
Ascaris lumbricoides and Ascarus suum
232
In what species are Ascaris species found?
Humans and pigs
233
What do Ascaris do to their host?
Live in small intestine, produce large amounts of eggs, and steal nutrients from hosts
234
What happens if Ascaris bursts inside of hosts?
Contents of body under high pressure, very toxic.
235
What is the life history of Ascaris?
Hatch in small intestine, larvae enter capillaries. Carried to heart, lung, and then bronchi. They are then swallows, mature, and start growing into sexually reproducing adults
236
A single female Ascaris can produce up to about ______ eggs per day
200 000
237
What are some symptoms of Ascaris infection?
Cough, fever, respiratory irritation, skin itching, can block bile/pancreatic ducts, enter appendix. Interferes with nutrition.
238
What is the major risk of the blood-travel stage of Ascaris infection?
May accidentally migrate to brain, kidney, eye, spinal cord instead of lungs. This can be where neurological damage occurs.
239
What are the two types of Toxocara parasites?
T. canis, T. cati
240
What occurs from Toxocara infectoin?
Toxocariasis
241
How can one become infected with Toxocara?
From eggs in water/damp soil. Usually children get it from feces of pets
242
How can cats/dogs acquire Toxocara?
From feces, milk, or even in utero
243
Taenia saginata comes from what type of food? How common is it?
From beef. Most common tapeworm in North America
244
Taenia saginata is ____m long
17m
245
Taenia solium come from what type of food?
Pork
246
Diphyllobothrium latum comes from what type of food?
Fish
247
Hymenolepis nana, Hymenolepis deminuta, and Dipylidium caninium all come from what kind of animal?
Cats, dogs
248
The anterior end of the tapeworm is referred to as the ____. What is present on it?
Scolex. Has suckers and rostellum (ring of hooks)
249
The anterior Scolex of the tapeworm produces a series of segments called what?
proglottids
250
How is tapeworm passed from hsot to host
Eggs passed in feces of definitive host, eggs ingested by intermediate host. Hatch, travel to muscles and organs with blood. Encyst as cysticerci.
251
How may animals ingest tapeworm?
From undercooked/uncooked flesh. Smokes, dried, salted meats can contain infective cysticerci. Cysticerci can develop into adult tapeworms in the gut
252
What is the difference between ingesting eggs and larvae of tapeworms?
We can become intermediate host if we ingest eggs - called cysticercosis
When we ingest larvae we become definitive hosts
253
What is it called when cysticerci of tapeworms live in the head/brain
Neurocysticerci
254
Briefly describe the lifecycle of a fish tapeworm
Definitive host releases eggs into water. Egg develops into coracidium, which onfects copepod. Metamorphoses into procercoid,which is taken in by a fish that eats the copepod. Inadequately cooked fish can harbour tapeworms
255
Sometimes the pletocercoid from fish develops into another one in people, referred to as _____
sparganosis
256
In MB top carnivore fish, infection rates may be as much as ____
70%
257
Tapeworm infection is referred to as ____. What are some symptoms?
Taeniasis.
| Weight loss, mautrition, abdominal pain, diarrhea, many people unaware until they evacuate proglottids
258
What is another way to obtain cysticercosis (other than ingesting infected water)?
Eggs may be moved from small intestine to stomach during vomiting
259
What are some symptoms of neurocysticercosis?
Epileptic seizures, personality problems, headache, buildup of intracranial fluid
260
Describe the life cycle of a fluke
miracidium > snail host > sporocyst > redia > cercaria (emerges from snail) > encysting on macrophytes as metacercaria > deifnitive host (which drinks water/ingests)
261
How long can flukes survive in the water?
4-15 days
262
How do the eggs of Fasciola species enter the feces?
Eggs shed in liver, travel down bile ducts to intestines
263
Swimmers itch is caused by what?
by Fluke cercaria entering human skin and causing very itchy immune reactions
264
What MB flukes can infect humans?
Fasciola hepatica and Fasciolopsis busci, opisthorchis (from dogs/cats)
265
How does one avoid swimmers itch?
towel yourself off immediately after swimming in a lake
266
Swimmers itch is otherwise known as?
Cercarial dermititis
267
What symptoms does Schistosoma cause?
fever, abdominal pain, weight loss, diarrhea, intestinal polyps, kidney failure
268
Where do Schistosoma flukes live?
in blood vessels
269
Where is schistosoma mansoni found?
Africa, SA
270
Describe the life cycle of Schistosoma mansoni.
Eggs laid in blood vessels > intestine > penetrate intestinal wall > feces > miracidia find snail > sporocysts > cercaria
271
Where can one acquire yeast infections?
Swmming, bathing, contaminated spas, aerosols
272
What diseases can be caused by yeasts?
Endocarditis, GI infection, kidney/bladder infections
273
Aspergillus fumigatus is the causative agent of ______?
Aspergillosis
274
How can one acquire Aspergillus?
May invade ear, nasal sinuses, skin, lungs, swimming, bathing, inhalation
275
In what cases is Aspergillus infection fatal?
Invasion of lungs
276
Hepatoxins are what shape?
Cyclic polypeptides (5aa: nodularins, 7aa:MC)
277
What are symptoms of acute algal hepatotoxin ingestion?
blood pools in liver, circulatory failure, and acute hepatotoxicosis (death)
278
What are symptoms of chronic algal hepatotoxin exposure?
Permanent liver damage, promotes liver cancer
279
What is the LD50 of MC?
50 micrograms/kg
280
What are some exposure routes for MC?
Ingestion, skin absorption, inhalation
281
How do algal lipopolysaccharide endotoxins work?
They are intracellular toxins, lipid-sugar molecules coming in many different varieties
282
What is the least studied cyanotoxin group?
Lipopolysaccharides
283
What is spirulina?
A species of Anabaena
284
Why is Spirulina used in supplements?
Takes away appetite - diet pill.
| High protein content - used in powders.
285
What are some risk factors for Spirulina contamination?
Often Spirulina are harvested in area that may contain Anabena and Aphanizomenon spp. - often contaminated with their toxins
286
What are some toxins produced by Dinoflagellates?
BMAA, saxitoxins, neosaxitoxins
287
What is one harmful bloom caused by Dinoflagellates?
Red tides (and subsequent paralytic shellfish poisoning)
288
How do saxitoxins work?
Prevents release of acetylcholine
289
Up to ___% of humans die of PSP
75%
290
Dinoflagellates contain two cell wall parts called what?
Epitheca and hypotheca
291
Bacillariophyta are otherwise known as ____
Diatoms
292
Chydrophyta are otherwise known as ____
golden algae
293
Diatoms and golden algae produce what in their cell wall?
Silica
294
Diatoms and golden algae bloom at what times of year?
Spring, late fall, sometimes in winter under ice
295
Diatoms use what to stay afloat despite their heavy cell walls? Is this safe for consumption?
They use oils, and these oils smell/taste fishy (totally safe)
296
The chlorophyta are otherwise known as what
green algae
297
How can green algae become toxic?
Some species produce toxins (chlorella, Scenedesmus), and may bioaccumulate heavy metals
298
The charophyta includes what groups? What are they?
Muskgrass, skunkgrass. They are large algae - resembling macrophytes but having no vascular tissue
299
The chariohyta do what to produce bad odours/tastes?
Produce sulphur, smell skunky
300
Why is it necessary to store municipal water?
IT may come from some distance, sometimes stockpiled for future use. Often stored in a basin or reservoir
Sometimes the reservoir is the primary source
301
What is the problems with storing water in artificial reservoir cells?
They are steep sided and therefore subject to thermal stratification and oxygen depletion. Decay and geosmin production near the bottom
302
Can algal blooms occur in reservoirs?
Yes. This is a problem because chemicals are often used to kill the algae.
303
What are some effects of chlorinated organic byproducts?
Produces thousands of chlorinated organic molecules, many being carcinogens. Chlorinated organics accumulate in fatty tissues
304
What are some problems with water chlorination?
Effectiveness depends on temperature (takes longer at lower temp.). Only partially effective for some organisms such as Yersinia, Strep, Staph, Legionella. Not effective at all for polio, Clostridium, protozoan cysts, nematodes, phenolic compounds, actinomycete/bluegreen odours. makes water taste like bleach. generates carcinogenic chlorinated organic byproducts.
305
What are benefits of chlorination?
Inactivates many enteric bacteria and viruses (reduced cholera, typhoid), kills algae. Oxidizes some organic compounds, converts bad smelling sulphides to sulphates/sulphur
306
What is a "chlorine residual"?
Chlorine residual must be present in the distribution system in order to kill some organisms that may grow during distribution.
307
What is an example of a trihalomethane?
CHLOROFORM
308
The current DW guideline for trihalomethanes? How does this compare tothe wHO?
100 micrograms/L - WHO is 30 micrograms/L
309
What are other sources of organic chlorinated exposure?
cola drinks, some instant coffee, solvents/degreasers/cleaners, treated wood, bleach, swimming pools/hot tubs, home well water chlorinators
310
How is it that cola products end up with high chloroform levels?
Chloroform used to remove cocaine from coca leaves
311
What is the amount of chlorinated organics in water directly related to?
Intensity of chlorination, length of time water is in contact with chlorine (residual in pipes continues to react with stuff), concentrations usually lower in winter,
312
Highest chlorination levels in Canada are found in ____. Why is this?
Whitemouth, MB. Because river goes through a bunch of livestock-land
313
Is chlorination needed for groundwater?
Nope, unless it is polluted
314
How are THMs absorbed?
Directly in GI from drinking water
315
THMs can be taken in in what ways?
Inhaled during showering, bathing, washing dishes, laundry, humidifiers - absorbed through skin as well
316
What do THMs do in the body?
Irreversible liver damage, CNS depression, tumors in liver/urinary, accelerates growth of existing tumors, promotes bladder/colon cancers, crosses placenta, delayed fetal development
317
THMs are synergistic with ____
ethanol
318
Describe the variation in THMs in MB?
Below detection limit in places that use groundwater, but may be very high in river surfacewaters polluted by agriculture/livestock (Red River, Whitemouth)
319
What are some ways to remove/minimize chlorinated byproducts in water?
Pretreat raw water with other chemicals (ex. Al coagulants), remove them after chlorination expensive). The best option is to also treat with another method such as ozonation
320
What is "superchlorination"?
Otherwise known as chlorine shocking or well shocking. Used to disinfect wells - done when new well is drilled, or to disinfect a single problem well (not whole aquifer).
321
Describe Ozonation as water disinfection?
Ozone gas used instead of chlorine. (used in Europe commonly)
322
What are advantages of ozonation of DW?
Breaks down into O2 - no toxic residual. No chlorinated byproducts, more effective than chlorine. Kills bacteria quickly, inactivates lots of viruses, spores, fungi, and even protozoan cysts. Oxidizes more organics, cyanides, phenols, nitrite > nitrate, oxidizes smelly sulphides. Precipitates Fe, Mn, many heavy metal ions.
323
What are disadvantages of ozonation?
More expensive, does not destroy actinomycete or bluegreen odours, doesn't oxidize THMs, no residuals left. May convert some things such as plastics (nonbiodegradable organics) to biodegradable version,s providing substrate for bacterial growth. Small amounts of toxic products may be formed (pesticide breakdown, natural organics)
324
What are advantages of UV light as a water treatment method?
Destroys viruses, bacteria, oxidizes a lot of organic compounds. Destroys colour/odour producing molecules, decomposes heavy metals, and destroys some organic carcinogens/neurotoxins
325
What is the best wavelength for UV water treatment> Is that attainable?
265nm, but the best we can do is 253.7nm
326
What are soem disavdantages of UV light as a water treatment method?
Does not destroy protozoan cysts (need external filtration), water must have low turbidity, humic compounds and Fe interfere, water may have to be pe-treated as a result. No residual in distribution system. Also very expensive (lamps last
327
Where is UV disinfection often used?
private homes
328
In which conditions can UV not be used?
If water is turbid/coloured, TCC >100MPN/100mL, electricity fluctuates in voltage, if there are protozoan cysts, if algal blooms are present, if lamp is over 2 years old
329
How can potassium permanganate be used for DW?
in some old-type rural home systems, small scale/emergency water disinfection, used in travellers water purification tablets - adds Mn to water
330
How can bromination be used for water treatment?
Not for drinking!!!!! used in spas or hot tubs
331
What is the purpose of aerating drinking water?
Improve quality (generally), especially beneficial for groundwater (which lacks oxygen), precipitating Fe and Mn.
332
What are some downfalls of aerating drinking groundwater?
driving out dissolved gases into the consumers home. (like H2S - can kill people)
333
What is "flotation" and how is it used to teat water
Air bubbles very slowly release nito water from the bottom, and as these bubbles rise they attract solid particles, forming a froth that can be skimmed off the surface. This allows wate to be treated for turbidity
334
How is sedimentation accelerated in the wpg DW treatment plant?
coagulants are added (such as aluminum sulphate) to clump fine sediments together and silica is added to make them heavier so they sink
335
What kind of filtration is used in many municipal water systems?
Water passed through series of sand beds, removes many microorganisms, protozoan cysts, parasite eggs.
336
What kind of filtration is used in home systems?
Home consumer may use ceramic filters. Activated carbon filters also work very well - remove trihalomethanes
337
describe the ion exchange system that water softeners use?
One type of ion adsorbed onto resin material, replced by another ion of same electrical charge. Ca, Mg, removed by cation exchanged resin, Na ions from water softener salt are substituted instead - Increases Na concentration in finished water
338
When should home water softeneers be used>?
between 300 and 700mg/L
339
What system is used to soften brackish water?
Dialysis membranes with weak electical currents (pull ions from water) - Electodialysis
340
What occurs during reverse osmosis treatment?
Pressure is applied to water and water molecules are squeezed through semi permeable membrane - solutes are left behind. Membrane must be changed regularly because it does acquire tears
341
What can get through reverse osmosis pores? How is this addressed?
some small molecules. Addressed by running the rest of the water through an activated carbon filter
342
What is necessary to have a reverse osmosis water system?
need high water pressure
343
How do activated carbon filters remove molecules?
Remove large molecules that may be missed by reverse osmosis - removes chlorine residual, organics, petsicides, atinomycete/bluegreen odours, some inorganics, heavy metals
344
What are disadvantages of carbon filters?
Efficiency declines with use and age, bacteria may grow on filter
345
How do ceramic filters work?
Don't work for chemicals, only particles. Come in different mesh sizes - remove fine particle,s bacteria, eggs, cysts but not viruses. Must be cleaned regularly. Bacteria are not killed and may gro on filter
346
What is the advantage of using distillation to treat water?
Low TDS
347
What are some disadvantages of using distillation to treat water?
Very expensive and uses a lot of electricity. Aggressive index very high (pH5.4), may contain high concentrations of volatile substances, no nutritive value, bacteria like Pseudomonas may still grow
348
What are the two kinds of distillation?
1. Batch - One batch at a time, needs to be manually refilled (not collected to plumbing system)
2. Continuous feed - Connected to plumbing, replenished automatically
349
How can freezing be used as a water treatment method?
Dissolved materials cannot become incorporated into crystal lattice structure of ice
350
Why is it that we must boil even ice before drinking it?
Pathogens are not affected by freezing - remain viable
351
Bottled water that claims to be from a glacier has what issues?
Is likely quite dirty due to atmospheric deposition
352
What must be added to concrete?
Well it's primarily made of gypsum (alkaline). Contains liquidizers, packing/porosity additives, additives to release air bubbles, swelling agents, bonding agents, permeability inhibitors, corrosion retardants, pesticidal additives, antiflaking additives, pigments, UV retardants
353
Why was asbestos added to pipes in Winnipeg?
To reduce corrosion of cement pipes.
354
Asbestos cement pipes in Winnipeg are ___% asbestos?
17%
355
What is asbestos?
Fibrous minerals (two types: amphibole and chrysotile).
356
What is the most common asbestos fibre in Canada. Is there a DW guideline?
Chrysotile. No guideline.
357
How are asbestos fibres counted?
Electron microscopy (fibers/L)
358
Are there natural asbestos sources?
They are present in Ontario/Quebec
359
ACP pipe is otherwise known as
Asbestos concrete pipe
360
Highest asbestos in water in the city is found in ___
Garden City
361
What are other sources of exposure to asbestos in our daily lives?
Construction materials, flameproof fabrics, shields, firefighters' gear, insulation (Zonolite), drywall, even children's toys
362
What does asbestos do?
Causes cancer after long lag period, may not be a direct carcinogen but instead interferes with detoxification
363
what cancer is caused only by asbestos?
Mesothelioma - cancer of inter-lung space under sternum
364
What are some ways of taking in asbestos?
Inhalation of aerosols (fibers lodge in alveoli), or can be ingested and work through intestinal wall into capillaries, where they are distributed all over the body
365
Asbestos is synergistic with ___
Tobacco smoke, PAHs, possibly radon gas
366
Where can asbestos be found in the home and car?
fireplaces, valves/seals/gaskets of cars, break pads of cars
367
How is asbestos mined in Quebec?
Open pit mines
368
Lead concentrations in tapwater are generally _____than in raw water
higher
369
Home built before 1946 in winnipeg likely have what kind of internal plumbing?
Lead
370
Homes built between 1946 and 1989 in winnipeg likely have what kind of plumbing and solder? What about after 1989?
Copper pipes with lead solder. After 1989, solders must have less than 0.2% lead
371
How does the city of Winnipeg attempt to reduce leaching of lead into water from pipes?
Phosphoric acid is added to water
372
____ aggravate(s) the rate of leaching of copper from pipes
Chlorination and manganese
373
Older types of pipes qare often being replaced by what?
Plastics!
374
What are some compounds foun d in plastic water pipes?
PVC, CPVC (chlorinated PVC), PB - all carcinogenic
375
What plastics are often used in waste lines?
ABS (acrylonitrile butadiene styrene) - Suitable only for waste lines!! - ALL SUPER CARCINOGENIC
