Lecture 2-___ Flashcards
___% of water is in oceans, glaciers, and polar ice caps
97.2%
___% of water is in oceans, glaciers, and polar ice caps
97.2%
Differentiate between the progressive, regressive, and flat rate of water pricing?
Progressive: The higher quantities you use, the higher your rate
Regressive: Those using high quantities generally pay less (ex. businesses subsidized by municipal/provincial taxes)
Flat rates: Same price per unit water regardless of how much is used
About ___% of the adult human body is water
70%
What are some of the long term impacts of substances carried by drinking water?
Influencing immunity, behaviour, IQ, reproduction, life expectancy
What are examples of some groups in Canada that may not have access to safe drinking water?
Aboriginal communities, rural residents, and northern communities
People generally use (more or less) water when they have a water meter
Less!
____% of all disease is spread by unsafe water
80%
Why was the new Winnipeg water treatment plant developed?
To deal with Cryptosporidium, a protist which grows from fecal contamination and is found in shoal lake. It cannot be killed by chlorination but instead only filtration
How does water quality influence deforestation?
When people need to boil their water, they often use wood, which contributes to global pollution and deforestation
Approximately _____L per day is considered to be what you need for daily life (adequate standard of living). How does this differ from urban areas and why?
50L.
100L in urban areas for effective sewer transport
____% of the global population has no access to safe water
26%
Average residential water consumption per person per day in Winnipeg is approximately
approximately 300L/person/day
Why was the new Winnipeg water treatment plant developed?
To deal with Cryptosporidium, a protist which grows from fecal contamination and is found in shoal lake. It cannot be killed by chlorination but instead only filtration
What are the primary things that domestic water use is related to?
Household income/property value, and climate
Approximately _____L per day is considered to be what you need for daily life (adequate standard of living). How does this differ from urban areas and why?
50L.
100L in urban areas for effective sewer transport
____/___ of the world’s food is grown on irrigated land
1/3rd
Average residential water consumption per person per day in Winnipeg is approximately
approximately 300L/person/day
How does Canada rank globally in terms of per capita water usage?
2nd to the U.S.
In Winnipeg the costs of water went up after the installment of what?
The installment of the new water treatment plant
How does Canada rank globally for water prices?
One of the lowest rates in the developed world.
What is the primary reason why some cities around the world are running short on water?
Groundwater depletion.
What are some measures to cut back on water consumption?
Ask consumer to cut back voluntarily (ha).
Rotate restrictions (ex. every second street can water their lawn on every second day)
Restrict size of surface area
Provide service only at certain hours of the day
Arrange to import water from a more distant source
How do storms affect sewage treatment in Winnipeg?
Storm sewers can overflow from summer rain so sometimes waste water is directly diverted into the Red River
What happens when organic compounds are put through a water treatment plant?
They are chlorinated, therefore becoming carcinogens (ex. trihalomethanes)
What is the guideline for trihalomethanes in Canada? How does it compare to WHO?
- WHO says 30 is too high.
What agencies deal with drinking water quality guidelines and which are the most stringent
WHO (most stringent), EPA (often more intense than Canada but not always), Canadian Task Force on Water Quality Guidelines, and Manitoba Water Quality Objectives (Manitoba Drinking Water Safety Act)
Why is it so hard to set up scientifically sound water quality guidelines?
IT is really hard to do research on the heath effects of many contaminants (latency periods are very long) , there are lots of complicating variables such as age and lifestyle
The _______ period is the time between first exposure and the time that you see symptoms of an ilness
Latency
Why is it that animal studies of water contaminants not useful?
Studies run for no more than 2 years - not enough time to identify effects of toxins - ex, cancer is very long term
What is toxicity?
The ability of a chemical to damage an organ system, disrupt a biochemical process or disturb an enzyme system in such a way that is causes clinical illness
Toxicity testing is based on what principle related to exposure to a toxin? Why is this not true for allergic reactions?
Based on the principle that intensity increases as dose increases. This is not true for allergic reactions because the first exposure (lowest amount) actually produces a less extreme reaction
Toxicity is expressed as LD50. What is this?
Expressed as amount per unity body weight that is lethal to 50% of organisms tested in a given time limit
Why is the LD50 sometimes not helpful when studying water contaminants?
Does not give a measure of chronic exposure
Why is animal toxicity testing often not accurate for humans?
Different animals are being used - the closest animal to us is monkeys but even monkeys have different immune systems and differences in toxicity
What is the NOEL level of a substance?
The “No observable effect level” - the level of a substance at which a change is viewed in the organism.
Why is NOEL often not a good guideline for toxicity?
Many effects are not easily assessed (ex. behavioural), or are too subtle to identify (ex. presence/absence of headache). There is huge variation in response to the same dose (even across males vs females, adults vs children). NOEL does not include carcinogens
When we as humans are exposed to chemicals in the environment, it is always is a cocktail of multiple contaminants. What does that mean in terms of response?
Sometimes they are antagonistic toward each other, sometimes they have additive toxicity, but the majority of the time they have synergistic toxicity (make each other worse)
Is synergistic toxicity often studied?
Nope. Toxicity data do not take that into account
TRUE OR FALSE: Canada manufactures DDT
True
_____ is the second leading cause of death in north america
Cancer
How does the Canadian government operate on an “innocent until proven guilty” basis for pharmaceuticals and food additives?
The Canadian food inspection agency allows
What are the primary parameters that determine what chemicals are on lists such as the Canadian Water Quality Guidelines?
- Known to be toxic (through the fundamentally flawed NOEL)
- Easily measurable (cheap)
- Likely to be present in some samples
Canada has a tendency to do what with water quality guidelines over time?
Reduce the threshold values
What are the different water quality guideline “types” found in Canada?
- Drinking
- Recreation
- Irrigation
- Livestock watering
- Protection of aquatic life (basically just fish)
In Manitoba, the ____ Act regulated public and private water supplies and distribution
Manitoba Public Health Act
The Manitoba Public Health Act regulations apply to what kind of systems?
Drinking water systems that have more than 15 service connections.
What group does water quality monitoring under the Manitoba Public Health Act?
Manitoba Conservation
How are municipal water supplies in Manitoba usually disinfected?
Usually chlorination, sometimes ozonation
What are the steps required to build a water treatment plant in Manitoba?
- Construction plan reviewed by MB conservation and Department of Health
- Facility built and water tested
- Disinfection (chlorination) and bacteriological limits set
- All monitoring will be by MB conservation
What is added to Winnipeg drinking water before it reaches citizens?
Sulphur, chlorine, phosphorous
What chlorine residual must be in water that is distributed to houses? How is this measured?
0.5mg/L. Measured daily and sent to MB conservation and the public health inspector
What are the coliform bacteria requirements for tap water
At least 90% of samples must have no total coliforms, and no one sample may have over 10. No fecal coliforms can be found.
If coliform bacterial requirements are exceeded, what is the procedure?
- Add more disinfectant
- Resample
- Issue warning
- More disinfectant - resample
- Boil water advisory issued
The _____ Act governs American drinking water quality. Are theses standards or guidelines?
Safe Drinking Water Act. They are legally enforceable standards
Is the American Safe Drinking Water Act more strict than Canadian guidelines?
Generally, yes
What are some different sources of drinking water and which areas use them most often?
Desalinated seawater (usually desert countries, reduced from 3.5% salt to 0.5% salt)
Groundwater
Surface freshwater
Define surface water
Any water exposed to the surface (the atmosphere)
Why is the presence of oxygen important for drinking water?
O2 kills anaerobes, oxidizes many harmful chemicals into harmless forms, precipitates dissolved iron, prevents some toxic materials (ex. hydrogen sulfide) from forming
At what time of year might some surface waters become anaerobic
winter - when organisms eat up all the oxygen in a lake
Why is exposure to UV light a positive thing for drinking water
Kills some microorganisms and degrades some toxic organics (ex. cyanide or anatoxin-a)
Why is the presence of aquatic macrophytes important for drinking water?
They control algal growth by releasing compounds that inhibit them and by sequestering nutrients
What are some downsides of relying on surface waters for drinking purposes?
Potential for algal blooms and subject to atmospheric fallout/environmental hazards, subject to pollution
What are different sources of pollution in Shoal Lake?
Agriculture, the winter road that takes supplies to Shoal Lake 40, cottages, boat traffic, runoff from roads
Aquifers extend from soil surface to up to ______km deep
0.8 km
Is there more surface water or groundwater on the planet?
Groundwater
About _____% of canadians drink groundwater
26%
Why is it that groundwater (as drinking water) usage has gone up over the past 20 years?
Most surface water is too contaminated
Why is it that we have no idea how many wells there are in Canada?
We do not require private citizens to report well drilling
There are two kinds of aquifers: _____ and _____
unconfined and confined
The impermeable layer on top of which an unconfined aquifer sits is called an _____. Unconfined aquifers have a _____ volume
Aquitard. Indeterminate
Describe confined aquifers
Squeezed between two aquitards, finite volume which is under pressure, and can emerge as an artesian spring/well
How can drilling wells spoil good aquifers?
Allows bad water to enter another level (otherwise known as intrusion), damaged well casings and heat pumps may affect water, or deep injection of hazardous waste can really fuck them up
Where has the water table level lowered in MB?
Lowe Farm, Winkler, that general area. Also, Charleswood, where buildings as young as 50 years old are having foundations crack, subsidence or sinking of homes
What are some disadvantages of using groundwater for drinking?
Main one is that there is no oxygen. Harmful anaerobes can grow, toxins like H2S can be produced, NH3 is not oxidized, Radon gas can be present, can contain radioactive substances in areas such as the Precambrian Shield, no UV breakdown of toxic substances, pathogens are preserved because water is cold
Why are gas stations a major source of groundwater pollution?
Underground gas tanks can be leaking for years without anyone noticing.
Very toxic substances are often injected deep underground in the town of _____, MB
Gimli, MB
How is groundwater contamination something that is not easy to detect?
Usually it cannot be tasted or smelled, and when it is reported MB conservation usually doesn’t do anything
What are some different ways in which toxic substance can enter the body?
Ingestion (via cooking, drinking, accidents)
Absorption (via skin, mucous membranes)
Inhalation (via aerosols, dusts)
injection (medical procedures, accidental penetration)
How does the acid environment of the stomach influence ingestion of contaminants
Promotes solubility of compounds that are weak acids. Ex. metals easily absorbed
What is enterohepatic recycling and how does it influence the absorption of toxic materials by the body?
Enterohepatic recycling is the process of blood being cycled from the small intestine to the liver to the bile and back to the small intestine. This results in many toxic substances cycling through the body, prolonging the amount of time they spend in the body
How does eating plants influence absorption of toxic substances?
Cellulose fiber binds to many toxic chemicals.
Why is that eating burnt toast can help in the event of a poisoning emergency?
Because activated charcoal adsorbs poison
The _____ is the primary site for bodily detoxification and the _____ is the secondary one
Liver, kidney
The ____ has another pathway where the residence time of poisons in the body can be prolonged
Bladder
What are some skin/hair products through which we may absorb toxic materials
jewelry, clothing, cosmetics, hygiene, grooming products, medical and dental devices
When can water droplets be inhaled?
When bathing, showering, swimming, using humidifiers, garden hose mist, steam from washing dishes
How does asbestos cause disease?
Asbestos lodges in the alveoli permanently and eventually leads to cancers
____,MB has the highest amount of chloroform in the water of any place in CANADA
Whitemouth
How does smoking affect the absorption of toxic substances?
Amplifies the effects of airborne pathogens
Many chemicals never leave the body. What is this referred to?
The “body burden” - the idea that many chemicals are not removed from the body and gradually increase in concentration as we age
Why is it that alcohol is smelled on the breath when drunk?
Because alcohol is removed from the body by exhalation
What are a few different ways in which chemicals can exit the body?
Sweat, urine, tears, exhalation, poop, breastmilk, saliva, bleeding, amniotic fluid, hair and nails
What kind of toxic substances are deposited in hair and nails?
Arsenic, many heavy metals
List the physical water quality parameters
Odour, colour, oil/grease, turbidity
Why are chemical water quality parameters considered more useful than physical?
They deal with specific chemicals, whereas physical parameters may be perfectly healthy
_____ is the most frequent type of complaint by consumers to water suppliers
Taste/odour
What are some sources of bad tastes/smells in drinking water?
Microorganisms (ex. actinomyces), produced during water treatment (ex. from chlorination), compounds from algal blooms, decaying plant/animal matter, oil, H2S gas, iron bacteria, tannins, metals, pesticides, industrial pollution, landfill leaching
If surface water becomes stratified in summer, sometime anaerobic bacteria grow in the low layers - what compound can be produced from that?
Hydrogen sulfide gas
How does low pH affect metals in water?
Low pH causes metals to become more soluble and affect the taste of water
The most common cause for colour change in surface waters is what? What colour does the water turn? IS this deadly?
Fulvic acids that come from decomposition of plant material, leaf litter, etc. Turns water brown but is perfectly safe to drink
In groundwater, what is the most common cause of brown water? Is it toxic?
Manganese/iron. Both are.
What is the water quality guideline for colour in Manitoba?
“There shall be no objectionable colour”
How is colour measured?
TCU = total colour units
Petroleum products are referred to as ______ under Canadian water quality guidelines
“Gasoline and its organic constituents”
______ molecular weight petroleum compounds can be tasted in water
Small
TRUE OR FALSE: All petroleum products are toxic
TRUE
Where would petroleum products that contaminate surface water come from?
Spills, leaking fuel tanks, lubricants, dumping of aircraft fuel, train derailments
How do petroleum products and other volatile organics react with the water?
Some sink below the surface, some float above
How is turbidity measured?
Nephelometer
Why is turbidity considered an issue?
May harbor microorganisms, some small particles like algae, asbestos, clay (absorbs heavy metals and pesticides), or calcium carbonate/lime (beneficial to health) appear.
How can turbidity be a problem in UV light disinfection systems?
Shields pathogens from being killed by UV light
What is total dissolved solids? What is it measured in?
All dissolved organic and inorganic matter in the water. Measured in ppm (mg/L)
Ideally, we want water to be between _____ and _____ TDS
100 and 150
How does high TDS affect water distribution?
Can coat pipes
How is TDS measured?
Electrode
TRUE OR FALSE: Hardness is the same as alkalinity
FALSE
What is meant by “hardness” of water? Where are the hardest waters in Canada?
Hardness is the total cations present in water, consisting of mostly Ca and Mg. Hardest waters are in Manitoba, Southern Ontario, and Saskatchewan
What is meant by “alkalinity” of water?
The ability of a water to neutralize acid
Metals are more soluble in ____ (more/less) alkaline water. How is this related to shoal lake?
less. This less alkaline water leaches things such as lead from pipes
What substances contribute to alkalinity of water
carbonate, phosphate, silicate, sulphide, ammonia, iron, magnesium, manganese, gasses (CO2), particulates
TRUE OR FALSE: Waters in Manitoba are generally very alkaline
TRUE
High alkalinity waters share what traits?
Great ability to sustain acid rain, acid pollution, less heavy metal toxicity,
Hard water is beneficial to health in what ways?
Lower risk of stroke, cardiovascular diseases, cerebral hemmorhage. Maybe due to less heavy metal absorption
___ to ____ mg/L of CaCO3 for hardness is considered “acceptable”
80-100mg/L
1ppm = __mg/L
1mg/L
TRUE OR FALSE: pH must be measured in situ. Why or why not?
TRUE, as pH changes over time
The _____ the pH is, the more corrosive it is
Lower
Heavy metals are more soluble in ___ metals
Heavy
What is higher pH associated with?
High hardness. Can also reflect problems such as eutrophication
As you approach a pH of ____, all fish will die
4
Generally the minerals absorbed at ___ (low/high) pH are more dangerous than minerals absorbed at _____ (low/high) pH
low, high
What are some problems caused by high chloride in water?
Water tastes salty, corrodes pipes/fixtures
High chloride water is found particularly in _____ of MB
Southwestern parts
The Canadian guideline for chloride in water is ____
250 mg/L
Water softener salt is made of _____. How does this affect rural (farm) houses?
NaCl. This can backlog into the septic field and create a very salty environment, which can leach into the groundwater over time
How does manure affect chloride concentrations in groundwater?
Manure in lagoons is very salty and can cause NaCl to leach into groundwater
What are some different sources of nitrogen in MB?
Livestock waste, fertilizers, sewage, cottages
How does mining affect nitrogen levels in Manitoba?
Gold mining is done using cyanide, which enters water systems and increases nitrogen levels
How soluble is ammonia?
Very very soluble
What are some sources of ammonia?
Runoff, leachings, sewage, industry, natural decomposition of organic matter, cleaners (ex. windex), anhydrous ammonia, mixed with irrigation water, excretion by aquatic organisms
What are some problems caused by the presence of ammonia in a water system?
Corrode distribution system, toxic to all animals, promotes bacterial growth
Is there a canadian drinking water guideline for ammonia?
No
What is one way to prevent ammonia from building up too much
Aerate the water, converting ammonia to nitrite (NO2)
The number one cause of mortality in Lake Winnipeg fish is _____ from Winnipeg sewage
ammonia
Levels of nitrite above ______mg/L indicate pollution
01.mg/L
Nitrite is about ____ as toxic as nitrate
10x more
Is there a Canadian drinking water guideline for nitrite?
Nope.
What is the primary concern with nitrite in groundwater?
There is almost no O2 in groundwater so nitrite cannot be converted to nitrate. This may lead to Methemoglobinemia: Blood vessels dilate, oxygen supply to brain/extremities reduced. Hemoglobin is converted to methemoglobin and blue skin, lips, nails (cyanosis) can occur. May lead to “blue baby disease”.
Often methemoglobinemia is misdiagnosed as ______
Sudden infant death syndrome
_____ is a dental product used to treat dry mouth that can induce methemoglobinemia
Biotene
Chronic exposure to nitrite results in ____
Chronic recurrent respiratory tract infections
If food is consumed with nitrite-high water, what reaction can occur?
Nitrites can form nitrous acid in the stomach, which will react with amines from food and form potent carcinogens (nitrosamines)
If oxygen is present in a water sample, the majority of nitrogen will be present as ______
Nitrate
The guideline for NO3 in Canada is ____mg/L and the guideline for NO3-N in Canada is _____mg/L
45mg/L, 10 mg/L
Nitrate toxicity results in water symptoms?
Gastric and prostate cancer, non-Hodgkin’s lymphoma, spontaneous abortion, affects on human behaviour
Bacteria that convert Nitrate to Nitrite can be found in the _____ of many animals
Gut
What are some additional places where we may be exposed to Nitrites sources?
Pickled/cured foods (nitrites or potassium nitrate), all cured/processed meat
Pickling salt is made of ___
Potassium nitrate
What is the purpose of adding nitrite to meat?
It is illegal not to add it to processed meat. Gives it a “zesty” flavour, preserves it, prevents botulinum production
Vitamin _ reduces the amount of nitrosamine production in the stomach after ingestion of processed meat
C
Why is it important to drain meat drippings from a pre-cured ham?
They contain over 2 times the amount of nitrosamines than the meat itself.
How does nitrate affect livestock?
Nitrate in food/water may cause illness or death in livestock, especially ruminants. Causes reduced weight gain, high susceptibility to disease, lower milk/egg production
How does nitrate get into forage and crop plants?
“Luxury consumption” - plants will take in more nitrate than they need when they are overfertilized. Animals will naturally avoid the plants that look like they have too much nitrate (looks a little blue-green), but when they are fed hay they do not have a choice.
What is a problem caused by excessive fertilization of crops?
Too much nitrogen in a plant results in deep green to blue leaves, and causes the plant produce Nitrates as well as Cyanide groups. When eaten the Cyanide groups break off in the stomach and nitrates react with the gut for a very unpleasant time
What vegetables are very prone to nitrate luxury consumption?
Beets, spinach, celery, lettuce, radishes
Out of the approximate 300 known nitrosamines, how many are known to be carcinogenic?
Over 98%
How does cyanide naturally occur in surface waters?
At very low levels from microbial activity and decomposition of plants. Tends to degrade via photolysis
The most toxic form of cyanide is what?
Free cyanide
What are some examples of metallocyanides?
Cyanide mixed with gold, ferrocyanide
Where can cyanide be found?
Gold mines, industrial effluents, electroplating, photography, dye (Prussian blue), pesticides, bluepencil (for drafting), extract of bitter almonds for baking
The human liver can deal with up to ___mg/day of cyanide
10mg/day
What happens when small concentrations of cyanide are ingested?
Liver converts it to thiocyanate which is slowly excreted by kidneys
What are effects of chronic low level exposure to cyanide?
CNS problems, thyroid problems, reduced fertility
What are effects of high exposure to cyanide?
Weakness, dizziness, headache, loss of appetite, shortness of breath
Cyanoglycosides are what?
Sugars binded to a cyanide group
Why is it important to remove pits as soon as possible when making choke cherry jelly?
because the pits are extremely toxic (cyanide), which leaches out in the cooking process
How are lima beans toxic? What has Canada done to combat this?
They have prussic acid in them (HCN). Canada prohibits himportation of beans >0.02%HCN (prussic acid). We also grow specially bred strains with less HCN
What are the symptoms of Favism?
From chronic fava bean consumption. Results in anemic condition, and Mediterranean peoples are especially susceptible.
What is phosphorous needed for?
ATP production, nucleic acid production, phospholipids, bone metabolism, biochemical energy transformations
There is no Canada drinking water quality guideline for Phosphorous as it is assumed to be non toxic. is this true?
No, as chronic low levels in drinking water is linked to colon cancer
Where can phosphorous come from in water?
Laundry detergents, dishwasher detergents, some concentrated cleaners.
American dishwasher detergents contain ___ (more/less) phosphorous than Canadian
less
What is “TSP”?
A powerful cleaned of trisodium phosphate which can cause intestinal discomfort if ingested
Phosphorous toxcity causes what symptoms?
Headache, garlic breath, supporating jaw sores
What is the canadian DW guideline for sodium?
200mg/L
sodium acts as a “builder” in laundry detergent - what does this mean?
attaches to greasy precipitated curds that come off of soaps
when is sodium input into surface waters the greatest?
In spring because of road salt
What are some commercial products that contain large amounts of sodium?
Caustic cleaners and water softeners
What can high Na intake contribute to?
Hypertension, CV disease, stroke
The most common form of sulphur in surface water is____
sulphate
The Canadian DW guideline for sulphate is ____mg/L. Why is this?
500mg/L, above which it acts as a laxative
What is the most common cause of atmospheric sulphur?
Burning of fossil fuels
What are some other sources of sulphur in waters?
Smelters, fossil fuel burning, pulp mills, fertilizers, volcanic activity, acid rain
Sulphate occurs as salts of what molecules?
Calcium, Sodium, Magnesium, Potassium, and some others
What types of manitoban lakes are most susceptible to sulphur? Why is this?
precambrian shield lakes, because they have little buffer capacity
The single largest source of sulphur dioxide in Canada is _____
Copper Cliff nickel mine, Ontario
How does acid rain affect Canada?
Many lakes are completely dead due to acid rain, especially in northern mining communities
Potassium sulphate is otherwise known as ______. Where does this come from?
Potash. Comes from old lakebeds, usually in Saskatchewan and Alberta
The threshhold at which one can taste the sulphate depends on what factors?
The type of sulphate salt
Where does hydrogen sulphide gas (H2S) come from initially
Anaerobic decompostion of organic matter
What are some sources of H2S?
Groundwater, dissolved gas, marshes, pulp mills, oil wells, petroleum refineries, sewage lagoons, manure
The Canadian DW guideline for H2S is ____mg/L
0.05mg/L
H2S is very common in Manitoban wells - how do we deal with this?
By aerating the water
Sometimes people in MB die of H2S exposure - how does this happen?
Usually it happens in Amish communities because they
At what level can people smell H2S?
Already at low (non toxic) concentraitons
How do people die of H2S exposure?
It inhibits cytochrome oxidase@
What are some problems with using trace elements in water quality testing?
Hard to detect
What are some sources of aluminum?
Fireworks, fossil fuels, smelters, mines, antaxids, buffered aspirins, antidiarrhea meds, vaccines, cookware/utensils, foil/food packaging, additive in food mixed, coagulant in water treatment
How was aluminum related to lung cancer in mining?
“McIntyre Powder”, made of aluminum, was forced upon miners
In the presence of _______ (common in MB plumbing), Al leaching is accelerated
Copper
How does drinking soft drinks contribute to overall Al concentration in the body?
People who regularly drink soda have higher bone, blood and liver aluminum
_______ (hard/soft) water causes more leaching of Al
Hard
Where does Aluminum accumulate in the body?
Brain/bones
What can be consumed with aluminum to enhance absorption?
Citrate
Elevated aluminum levels can be linked to what diseases?
Rickets, alzheimers/dementia
How does aluminum affect Alzheimer brains?
Cofactor in the formation of neurofibrillary tangles - increases the risk of Alzheimers
What consumer products have large amounts of antimony present?
Some eyeshadow, drugs (ex. leishmaniasis drugs),
What conditions can be caused by antimony?
Increases action of thyroid, implicated in sudden infant death syndrome. Causes weight loss, diarrhea, cardiac problems, liver problems, reproductive problems, carcinogen
How is antimony poisoning detected?
Testing sweat
Taste threshold for antimony is 0.6___g/L
0.6mg/L
Where can arsenic be found in the environment/human habitats
Fossil fuels, smelters, mines, industrial effluents, landfills, insecticides, allots, paints, rodenticides, fungicides (wood preservatives), chemical warfare agents, chinese traditional medicine, seafood (mussels), drinking water (ex. china)
What food usually has arsenic contamination?
RICE! BUY RICE THAT ISN’T FROM ASIA
What is the canadian drinking water guideline for arsenic?
10micrograms/L
How much arsenic is found in Shoal Lake? How did it get there?
3micrograms/L. Gold is extracted from arsenopyrite, which leaches in tailings. There are multiple mines just by shoal lake
Average daily consumptino of arsenic is ___-____mg
12-50mg
Each metal contaminant induces a response in your body that creates a protein called a _____. After your body cannot produce more of these, the meta becomes toxic
Metallothionein
Where does arsenic accumulate?
Hair, nails, bone, muscle, skin
Arsenic in water is associated with what cancer?
Skin cancer
What disease can result from arsenic poisoning?
Blackfoot disease (results in gangrene because of poor circulation). This has a latency period of up to 40 years
How is arsenic an example of how testing chemicals on other animals is not helpful?
Ingested arsenic is not carcinogenic in humans
Arsenic and _____ are synergistic
fluoride
What are some sources of Barium in the environment?
Electroplating, rat poison, brazil nuts
Barium causes what symptoms in humans?
Muscle poison, GI distress, tingling of fingers and toes, mimics digitalis poisoning, affects pacemaker of heart, hypertension, competes with calcium (ex. neurotransmitters), reproductive problems, incoordination and low back pain
How is Barium used in the medical sciences?
For X-ray contrast tests
Where can boron be naturally found in the environment?
Groundwaters (ex. hot springs)
The highest concentrations of boron in Canada are found in ___ and ___
Sask and M
The Canadian DW guideline for boron is ____mg/L. How does this measure up to the US equivalent?
5mg/L. USA is 0.6mg/L. shit
Where can boron be found in consumer products?
Enamels, glass, fluxes, sweet taste (used in ant traps), some water softeners, cleansers, used as antiseptics, some mineral waters, pesticides, brain tumor drugs, many mushrooms
How is Boron taken into the body
Needed for proper brain function, and is generally completely absorbed in the GI. It can cross the placenta and be fetotoxic. Accumulates in bone. Boron toxicity is associated with headache, fever, GI distress, red eyes, sunburn-like reaction
Boron is synergistic with ____
aluminum
Where is fluorine found in human products
insecticides, fungicides, rodenticides, anthelminthic drug for Ascaris, polishes silver, copper, brass, many others
Where does the fluorine in our drinking water come from?
by-product from fertilizer….
Why is fluoride added to water? Does it work?
to reduce tooth decay - but it only works on DEVELOPING teeth - children
At what levels does fluoride become dangerous?
Tooth discoloration over 1.5mg/L, osteoporosis 4-6mg/L, linked to lowered IQ in children
Where are we acquiring fluoride in the environment?
Toothpaste (average 1000mg.L), mouthwashes, fluoride gels
What are some symptoms caused by fluoride intoxication?
Weight loss, anemia, abdominal pain, diarrhea, sweating, depression, restlessness, hyperirritability, mutations, increases lead deposited in brain
____% of the total body burden of fluoride is in the bones
98%
What are some symptoms of chronic long term fluoride intake
Discolored teeth, brittle enamel, brittle bones, fused vertebrae/calcified ligaments
What is Addison’s disease?
Chronic poisoning caused by fluoride with patches of brown discoloration
What is fluoride synergistic with?
Increases the amount of lead entering the brain
What is the Canadian DW guideline for selenium?
10 micrograms/L
What is a major topical source of selenium?
Dandruff shampoo
What foods are good bioaccumulators of selenium?
Garlic, brazil nuts
What are selenoproteins?
Proteins produced by selenium entering a molecule when it should be sulphur, which are very very useless. Added to mRNA at the UGA codon.
Selenium antagonizes ___ and ___
Cadmium, mercury
What are some symptoms of selenosis?
CNS effects, GI problems, sulphury breath, hair loss, cracked fingernails, anemia, tooth decay, heart/liver inflammation, liver cancer
Silicon is the ____ most common element in the earths crust
2nd
Silicon antagonizes _____ in small amounts
Aluminum
What is silicon used for in the body?
Bone and connective tissue formation
What happens if you are deficient in silicon
Less Ca and Mg deposition in bone
Where is silicon found in nature and consumer products
Groundwater, hot springs, powdered mixes, seasonings
How are aluminum and silicon related?
Aluminum goes up in body, silicon goes down
The older a human is, the ____ slicon they have
less
What happens when too much silicon is ingested?
Inhibits antioxidant enzyme activity: Superoxide dismutase, catalase, glutathione peroxidase
What is the DW guideline for silicon
There is none
What are heavy metals defined as?
Electropositive elements with density >5 g/cubic centimeter
Are all heavy metals useless in the body?
We still need tiny amounts of them for certain biochemical processes, ex. iron forms hemoglobin
Why are organic forms of heavy metals far more concerning?
The addition of, say, a methyl group, allows the molecules to enter through the cell membrane. This means they can easily enter the skin, gut mucosa, or blood brain barrier.
What defenses does the body have against metals?
A limited ability to inactivate heavy metals - using metallothionines (different one for each different metal. As exposure increases, MT production does too and they are stored in the liver. Once MT capacity is exceeded, toxicity occurs
The total content of a given metal in our body at any given point in time is called ____
Body burden
What is the average body burder (mg) of lead in a 70kg person
150mg
what is the “biomagnification factor”?
How much more of a toxic substance is in the body in comparison to what was in the original food (basically, toxins can be bioaccumulated)
Are heavy metals uniformly distributed throughout the body?
No, certain ones target specific organs (ex. liver, kidneys most common)
What are some environmental sources of beryllium?
Fossil fuels, hickory smoked food, mines, electronics, ceramics, nuclear weapons
Which plants bioaccumulate beryllium?
hickory, tobacco
Up to ___% of ingested beryllium s absorbed
40%
What happens to beryllium after it is absorbed into the body?
Allergic reactions common, it’s not excreted well (deposited mostly in bones)
What are some symptoms of berylliosis?
Weight loss, enlarged liver, metallic taste in motuh, DNA damage, cancer
What is the most common symptom of heavy metal poisoning?
metallic taste in mouth
Where is bismuth found in the environment?
Tungsten-bismuth-tin shot for waterfowl hunting, drugs to treat ulcers.heartburn, travellers diarrhea drugs - also root canal filling materials
Where does bismuth accumulate in the body?
kidneys
What are some symptoms of bismuth poisoning?
Bad breath, mouth/gum ulcers, loss of appetite, “bismuth line” on gums, diarrhea, sore throat, neurotoxicity, depression, panic attacks, hallucations, may be misdiagnosed as mad cow or alzheimer
What are common sources of bismuth poisoning?
Extended use of pepto bismol or subscription for too much
The Canadian DW guideline for bismuth is ____mg/L
THERE IS NONE!!!
Where is cadmium found?
Fossil fuels, mines, smelters, metal and plastic industries
What are human sources of cadmium?
cheap jewelry, aluminum solder, alloys, batteries, mushrooms (bioaccumulate), some crops (if fertilized by sewage sludge, subject to acid rain), stabilizers in plastics
What are some food sources of cadmium?
Shellfish, crustaceans, the livers of livestock and poulty
What happens to cadmium once it is in the body?
Accumulates in liver and kidneys, and it is not well excreted (.5life of 10-30years) - body burden increases with age
The Canadain DW guideline for cadmium is ___ micrograms/L
5
What is the disease associated with cadmium toxicity referred to as?
Itai Itai disease
What symptom is considered a “warning bell” for cadmium intoxication?
Loss of sense of smell
What are some symptoms of Itai-Itai disease?>
back/joint pain, kidney problems/cancer, insomnia
Cadmium is antagonized by many other metals - list them
Zinc, copper, calcium, selenium, molybdenum, iron
Where is chromium found?
Fossil fuels, smelters, metal plating, cement, paints, bleaches, disinfectants, tanning industry (leather dyes), dental prostheses, crops (fetilized with sewage sludge), antacids, radiological tracers
The Canadian DW guideline for chromium is ___ micrograms/L
50micrograms
What are some positive uses for chromium in the body?
Used in collagen, protein, lipid metabolism, depresses seum cholesterol
Whet happens when someone has chromium deficiency?
glucose intolerance, reduced response to insulin: misdiagnosed as diabetes
atherosclerosis - usually in diets high in refined cereals
Where does chromium accumulate in the body?
All human tissues, but particularly brain, kidney, liver, skin, muscle, fat
What substances reduce chromium toxicity?
zinc, vitamin c
Where is cobalt found?
Mines, smelters, alloys, paints, foaming soaps, dental prostheses
Where is there a lot of cobalt in MB?
Flin Flon
Why is it that beer drinkers are very susceptible to cobalt poisoning?
Cobalt is added to beer to create foam and alcohol is synergistic with cobalt
Where is cobalt stored in the body?
liver, kidney, heart, fat
How toxic is copper?
Not generally very toxic to humans
Where do we find copper in the world?
Fossil fuels, mines, smelters, alloys, plating, copper/brass cooking vessels, copper plumbing, water from hot water tanks, copper sulphate (algaecide)
Where is copper found in the body?
In red blood cells it is erythrocuprein and in plasma bound to globulin
What are some symptoms of copper poisoning?
Steady abdominal pain, diarrhea, headache, dizziness, liver damage, metallic sweet taste in mouth, high white blood cell counts
In what situations does circulating Copper go up
pregnancy, infections, kidney + liver disease, heart attack, leukemia, estrogen therapy, psoriasis
What is Wilson’s disease?
As a result of a single autosomal recessive gene - copper accumulates in brain and liver because of reduced ability to synthesize ceruloplasmin
Describe “Menke’s kinky hair syndrome”
Due to a defect in absorption of Copper in small intestine - progressive brain disease of male infants. Results in slow growthm kinky hair, and cerebral gliosis
How is copper related to Hodgkin’s disease>
Activity of lymphoma correlated with increase plasma copper concentrations
About half of the body burden of iron is in what molecule?
Hemoglobin
What occurs when one is deficient in iron?
ANEMIA
What are the forms of iron?
Divalent (ferrous) iron - soluble in anoxic conditions
Trivalent (ferric) - insoluble.
What is the DW guideline for iron and why is it set at that?
30 micrograms/L - mostly an aesthetic guideline
What effects does iron have in water?
Form scale on pipes/taniks, can stain laundry, affects taste/appearance
What is hematochromatosis?
Genetic disease causing iron to accumulate in the body. Results in symptoms such as weakness, fatigue, joint pains, anemia (iron in plasma, not erythrocytes), year round sun tan, easily bruising, fluid retention, bolting
What are some sources of lead?
Fossil fuels, mines, smelters, potter glaces, paints, lead shot, lead crystal, cheap jewelry, plastics, hair dyes, cosmetics, pewter, chinese traditional medicine, hungarian paprika, ayurvedic treatments, tinned foods, lead in candle wicks, cheap mustard
Leaded gasoline is found in the form of ____
Tetraethyl lead
At the DuPont plant in New Jersey, over 300 workers got sick from tetraethyl lead. What happened?
They hallucinated that bugs were crawling all over them
What kind of food/liquid vessels can lead to food poisoning?
Pewter dishes, Lead Glass
Where does lead go once absorbed by the body?
Incorpoated into bones, teeth, liver, kidneys
____ is the most common human metal posioning
Lead
What symptoms occur during lead poisoning?
Neurotoxicity , GI problems, cramps, hypertension
What are some problems that dentists may have as a result of chronic mercury exposure?
Pink extremities,
What is Minamata disease?
Chronic methylmercury (organic) exposure that developed in Minamata, Japan, from effluent from plastics factory poisoning seafood. This resulted in many CNS symptoms such as numbness, tunnel vision, tremors, causes permanent disability, death of brain cells, crosses placenta
How does minamata disease differ from ____ disease?
Minamata is chronic organicm ercury exposure and ___ is chronic inorganic mercury exposure
The highest methylmercury contamination in the world is in Canada. Where and why?
James Bay area, Quebec
Where is the highest methylmercury present in MB?
South Indian Lake, Cross Lake
What is “Plumbism”? what are some symptoms?
LEad poisoning. Acts as a neurotoxin resulting in weight loss, fatigue, GI problems, abdominal cramps, hypertension, depression, irritability, kidney damage, gastric tumours, miscarriage
How does mercury react with other compounds?
Synergistic with nitrite, with antagonists including selenium, cadmium, zinc
Why are men considered more susceptible to mercury poisoning?
Estrogen can lower mercury uptake
How can we lower our mercury levels?
Don’t eat tuna, and limit carnivorous fish consumption, do not eat fish from Hydro reservoirs, ask for alternative dental fillings, wash potatoes thoroughly , don’t handle fluorescent bulbs with bare hands
How do different foods interact with lead in the body?
Pb inhibits uptake of Ca, will absorb more Pb. Fe and Zn deficiencies increse Pb absorption - linked to ADHD
What is manganese and in what water systems is it most often found?
A metal that forms alloys with iron, Al, etc. some salts of it are highly soluble and it is found in grounwater primarily
Where can we acquire molybdenum?
Fossil fuels, mining, smelting, industrial effluents, fertilizers - bioaccumulates in crops
What is the Canadian DW guideline for molybdenum?
We have none
How does molybdenum interact with the body?
Absorbed in small intestine, deposited primarily in bones
What happens to livestock when there is too much molybdenum in forage plants?
“Teart disease” - causes Cu and Zn deficiency
How does molybdenum interact with other potential toxins?
Synergistic with fluoride. Mo antagonized by copper, so Cu is antidote for molybdenum poisoning and Mo decreases Cu uptake
What are symptoms of molybdenum poisoning?
GI distress, anemia, headache, slowed growth, cancer activation
Where do we acquire nickel?
Fossil fuels, mines, smelters, corrosion resistant alloys (ex. stainless steel, not the end of the worls), nickel-cadmium batteries, mushrooms, leafy veggies, costume jewellery, coins, piercings
What is the canadian DW guideline for nickel?
There is none
How does Manganese interact with bacteria?
Oxidized and precipitated by manganese bacteria
Where is manganese found?
fossil fuels, mines, fertilizers, diesel fuel, fungicides, inks, preservatives, batteries,
What is the Canadian DW guideline for manganese and how does it compare to Shoal Lake?
5 micrograms/L
2-9 micrograms/L
How is manganese used in the body?
co factor for many enzymes, used in respiration and glycolysis. Necessary for bone and cartilage development.
Is nickel needed in the body?
Believed to be an essential nutrient
What is nickel skin sensitivity called?
Nickel itch
How much nickel is absorbed through the GI tract after ingestion?
1-10%
What are the results of Ni poisoning?
Metallic taste in mouth, loss of sense of smell, gum inflammation, elevated blood glucose:mimics diabetes, crosses placenta, cancers (prostate)
How does nickel interact with other compounds?
synergistic with copper, but manganese antoginizes nickel
Where does silver come from in the environment?
Electronics, hotography, mirrors, plating, disinfecants, some home water treatment systems, burn treatment creams, silverware, surgical clips, acupuncture, mushrooms, fish
What is the Canadian DW guideline for silver?
There is none, but there used to be (50micrograms/L)
Where does manganese accumulate in the body?
liver, kidneys, pancreas, intestine
What are some symptoms of manganese poisoning?
IT is a neurotoxin causing irreversible neurological damage: headaches, increased tears, behavioural changes, irritability, compulsive behaviour, lymph cancers
How does silver interact with food?
Binds to sulfhydryl groups (ex. egg on silver spoon)
Silver poisoning is referred to as _____ and occurs when body burden exceeds _______g
Argyria, 1 g
What happens during Argyria?
Blue-grey discoloration of skin, bluish discoloration of whites of eyes, enlargement of heart ventricles, neurological problems such as lethargy, manic depression
Where does silver accumulate in the body?
spleen, liver, bone, but mostly skin and eyes
Wh yis there no guideline for Tantalum?
Because it is extremely rare (except it is mined in MB!!!)
Where can we find tantalum?
Surgical tools, staples/clips, implants, dental prostheses, electronics
What is the Canadian DW guideline for mercury?
1microgram/L
What are some sources of mercury in the environment?
fossil fuels, mines, thermometers, blood pressure monitors, pulp mills, septic tanks, pesiticdes, fungicides, vaccines, fluorescent lightbulbs, FISH
What is a source of mercury more specific to MB?
Hydro reservoirs
Where can thallium be found?
Roden poison, wells (from landfills), medical diagnostic tests, fireworks, cheap jewellery, depilatorym treatment for ringworm in the past
Which form of mercury is more toxic? (organic or non-organic)
ORGANIC - much more is absorbed into body (80%-100%)
Where is mercury absorbed in the body?
through skin or GI tract
What are symptoms of thallium poisoning?
Sperm do not mature, permanent impairment of memory, liver/kidney damage, very popular for murder, used in attempted abortion
Symptoms of thallium poisoning start _____-____ days after exposure
2-3
Where does Tin come from?
fossil fuels, mines, pipe solder, solder in some canned foods, fluoridates toothpaste, pewter, seafood
Is tin needed in the body?
Needed for some redox reactions, heme metabolism, ivolved in metaboilism of Cu, Zn, Fe
How does tin enact toxicity?
Inhibits important enzymes such as succinate dehydrogenase
How is mercury used in the medical industry?
Surgical dressing, ointments (or used on cuts), merthiolate and thimerosol used in injectibles and vaccines, syphilis treatment, contact lens solution
Inorganic tin poisoning is called ___ and results in what symptoms?
Stannosis. Results in GI distress, blurred vision, anemia, calcium deficiency, interferes with Zn absorption and retention
____ is a tin compound among the most toxic compunds known. where is it found?
Organotin found in fungicides in pipes, fishnets, marine antifouling paints
How has mercury been used in dental applications?
Used mostly in fillings, with daily exposure leaching into blood,. Removal of fillings is followed by drop in blood levels
What are some symptoms of mercury poisoning from fillings? What can make the problem worse?
fatigue, lower hemoglobin levels, higher risk of cardiovascular disorders. Eating acidic foods, grinding teeth, or chewing gum can release more mercury from the fillings.
