ENV221 MULTIDISCIPLINARY STUDIES
ON THE ENVIRONMENT FINAL EXAM
QUESTIONS WITH CORRECT
ANSWERS
Lead poisoning interferes with normal development in the brain
Lead poisoning - Answer-Lead buildup in the body causes serious health problems
Symptoms: headaches, irritability, reduced sensations, aggressive behavior, difficulty
sleeping, abdominal pain, poor appetite, constipation, anemia
Additional complications for children: loss of developmental skills, behavior, attention
problems, hearing loss, kidney damage, reducing IQ, slowed body growth
Lead is more harmful to children as it can affect developing nerves and brains
Mercury - Answer-Highly toxic element that is found both naturally as an introduced
contaminant in the environment
Can't get rid of it because it occurs naturally
One of the most persistent bio accumulative toxins
It is believed that human activities have doubled or tripled amount of mercury in the
atmosphere
Current concern around coal fired power plants being most significant anthropogenic
source of atmospheric mercury emissions
Approximately 60% of mercury emissions transported far beyond sources
People are exposed to mercury through eating contaminated fish and wildlife at the
top of the aquatic food chain
Eating wild doesn't mean you aren't exposed to these toxins
Risk of exposure when bulbs/batteries break, proper disposal is important
Endocrine Disrupting Chemicals (EDCs) - Answer-Synthetic organic compounds
Disruption occurs when synthetic chemicals mimics or blocks hormones and disrupts
body's normal functions
After normal hormone levels, halt or stimulate production of hormones, changing way
hormones travel through the body
Suspected endocrine disruptors - Answer-Dioxin, PBBs, DDT, bisphenol A,
polybrominated diphenyl ethers, Phthalates
,Receptors on cell's surface are waiting for hormone to come
Flame Retardants - Answer-Couches, office chairs, mattresses, nail polish
Phthalates & Parabens - Answer-Nail polish, perfume/fragrance, makeup, personal
care products
Perflourinated Compounds (PFCs) - Answer-Non-stick (Teflon) cookware, water and
stain-resistant clothing and furniture
Polychlorinated Biphenyls (PCBs) - Answer-Fluorescent bulbs, oil-based paint,
caulking
- Hormone disruptors, carcinogens, and neurotoxic
Volatile Organic Compounds (VOCs) - Answer-Cleaning products, air freshener
sprays
No smell is a good smell
If you smell it, it is a volatile organic compound
Polybrominated Diphenyl Ethers (PBDEs - Flame Retardants) - Answer-Ubiquitous
since standards now require most household products to be flame retardants:
furniture, electronics, baby products/clothing
E.g. some polyurethane foam treated with 10-30 wt. % of PBDEs
Foamy chairs were banned in this lecture hall
Great Lakes - Answer-All 5 great lakes contain levels of PBDEs
Studies of Gt Lakes fish from 1980-2000 has found concentrations increasing
exponentially with doubling every 3-4 years
Many impact memory problems and disruptions to thyroid hormone
Hypothesis blamed rise in attention-deficit-hyperactivity disorder
Bisphenol A (BPA) - Answer-A synthetic industrial chemical land used to make a
hard, clear plastic known as polycarbonate
Used in many consumer products, including reusable water bottles and baby bottles,
sports equipment, medical and dental devices, dental composite (white) fillings
Also found in epoxy resins, which act as a protective lining on the inside of metal-
based food and beverage cans
Classed by Government of Canada as a hormone disruptors
Canada was the first country in the world to take action on Bisphenol A
Identifying BPA Plastics - Answer-There are 7 classes of plastics used in packaging
applications
Type 7 is the catch-all "other" class, and some 7 plastics are made from Bisphenol A
When such plastics are exposed to hot liquids, bisphenol A leaches out
Type 3 can also contain Bisphenol A
Impacts - Answer-Allergenic- causes allergies
, Neurotoxins- damages or destroys nerve tissues
Mutagens- induce or increase the frequency of mutation in organisms
Teratogens- causes malformation of an embryo or fetus
Carcinogens- cancer causing agent
Endocrine hormone disruptors
Allergies are more common now than they were in the past
Bioaccumulation - Answer-Accumulation of a substance in the tissue of a single
organism
Bio magnification - Answer-The increase in concentration of pollutants such as POPs
and heavy metals at higher levels in the food chain
Measuring toxicity - Answer-The dose makes the poison - Paracelsus, 1540
Some determinants toxicity:
- Amount of exposure (dose)
- Frequency of exposure
- Who is exposed? - genetic makeup & how well body's detox works
- How material is delivered?
- At what rate?
- Which route of entry?
- What medium?
How is toxicity determined? - Answer-Stimulations
Tissue cultures
- Usually animal models
- Appropriateness
- Dioxin 5000x more toxic to guinea pigs than hamsters?
- Of 226 chemicals carcinogenic in rats or mice, 42% caused cancer in one species
but not the other
How do we evaluate health risks to humans? - Answer-Retrospective studies in
which a group of people exposed to the risk factor (whether it's a toxin, a pathogen,
or other risk factor)
Compared to a "control" (actually a reference population) unlikely or at least less
likely to have been exposed
Prospective studies in which you choose groups to follow and wait
Why is it so difficult to establish cause and effect relationships with environmental
exposures? - Answer-Number of modes of action
- Directly via air or water
- Indirectly via bioaccumulation/magnification
Impacts are chronic rather than acute
Concentrations are extremely low
ON THE ENVIRONMENT FINAL EXAM
QUESTIONS WITH CORRECT
ANSWERS
Lead poisoning interferes with normal development in the brain
Lead poisoning - Answer-Lead buildup in the body causes serious health problems
Symptoms: headaches, irritability, reduced sensations, aggressive behavior, difficulty
sleeping, abdominal pain, poor appetite, constipation, anemia
Additional complications for children: loss of developmental skills, behavior, attention
problems, hearing loss, kidney damage, reducing IQ, slowed body growth
Lead is more harmful to children as it can affect developing nerves and brains
Mercury - Answer-Highly toxic element that is found both naturally as an introduced
contaminant in the environment
Can't get rid of it because it occurs naturally
One of the most persistent bio accumulative toxins
It is believed that human activities have doubled or tripled amount of mercury in the
atmosphere
Current concern around coal fired power plants being most significant anthropogenic
source of atmospheric mercury emissions
Approximately 60% of mercury emissions transported far beyond sources
People are exposed to mercury through eating contaminated fish and wildlife at the
top of the aquatic food chain
Eating wild doesn't mean you aren't exposed to these toxins
Risk of exposure when bulbs/batteries break, proper disposal is important
Endocrine Disrupting Chemicals (EDCs) - Answer-Synthetic organic compounds
Disruption occurs when synthetic chemicals mimics or blocks hormones and disrupts
body's normal functions
After normal hormone levels, halt or stimulate production of hormones, changing way
hormones travel through the body
Suspected endocrine disruptors - Answer-Dioxin, PBBs, DDT, bisphenol A,
polybrominated diphenyl ethers, Phthalates
,Receptors on cell's surface are waiting for hormone to come
Flame Retardants - Answer-Couches, office chairs, mattresses, nail polish
Phthalates & Parabens - Answer-Nail polish, perfume/fragrance, makeup, personal
care products
Perflourinated Compounds (PFCs) - Answer-Non-stick (Teflon) cookware, water and
stain-resistant clothing and furniture
Polychlorinated Biphenyls (PCBs) - Answer-Fluorescent bulbs, oil-based paint,
caulking
- Hormone disruptors, carcinogens, and neurotoxic
Volatile Organic Compounds (VOCs) - Answer-Cleaning products, air freshener
sprays
No smell is a good smell
If you smell it, it is a volatile organic compound
Polybrominated Diphenyl Ethers (PBDEs - Flame Retardants) - Answer-Ubiquitous
since standards now require most household products to be flame retardants:
furniture, electronics, baby products/clothing
E.g. some polyurethane foam treated with 10-30 wt. % of PBDEs
Foamy chairs were banned in this lecture hall
Great Lakes - Answer-All 5 great lakes contain levels of PBDEs
Studies of Gt Lakes fish from 1980-2000 has found concentrations increasing
exponentially with doubling every 3-4 years
Many impact memory problems and disruptions to thyroid hormone
Hypothesis blamed rise in attention-deficit-hyperactivity disorder
Bisphenol A (BPA) - Answer-A synthetic industrial chemical land used to make a
hard, clear plastic known as polycarbonate
Used in many consumer products, including reusable water bottles and baby bottles,
sports equipment, medical and dental devices, dental composite (white) fillings
Also found in epoxy resins, which act as a protective lining on the inside of metal-
based food and beverage cans
Classed by Government of Canada as a hormone disruptors
Canada was the first country in the world to take action on Bisphenol A
Identifying BPA Plastics - Answer-There are 7 classes of plastics used in packaging
applications
Type 7 is the catch-all "other" class, and some 7 plastics are made from Bisphenol A
When such plastics are exposed to hot liquids, bisphenol A leaches out
Type 3 can also contain Bisphenol A
Impacts - Answer-Allergenic- causes allergies
, Neurotoxins- damages or destroys nerve tissues
Mutagens- induce or increase the frequency of mutation in organisms
Teratogens- causes malformation of an embryo or fetus
Carcinogens- cancer causing agent
Endocrine hormone disruptors
Allergies are more common now than they were in the past
Bioaccumulation - Answer-Accumulation of a substance in the tissue of a single
organism
Bio magnification - Answer-The increase in concentration of pollutants such as POPs
and heavy metals at higher levels in the food chain
Measuring toxicity - Answer-The dose makes the poison - Paracelsus, 1540
Some determinants toxicity:
- Amount of exposure (dose)
- Frequency of exposure
- Who is exposed? - genetic makeup & how well body's detox works
- How material is delivered?
- At what rate?
- Which route of entry?
- What medium?
How is toxicity determined? - Answer-Stimulations
Tissue cultures
- Usually animal models
- Appropriateness
- Dioxin 5000x more toxic to guinea pigs than hamsters?
- Of 226 chemicals carcinogenic in rats or mice, 42% caused cancer in one species
but not the other
How do we evaluate health risks to humans? - Answer-Retrospective studies in
which a group of people exposed to the risk factor (whether it's a toxin, a pathogen,
or other risk factor)
Compared to a "control" (actually a reference population) unlikely or at least less
likely to have been exposed
Prospective studies in which you choose groups to follow and wait
Why is it so difficult to establish cause and effect relationships with environmental
exposures? - Answer-Number of modes of action
- Directly via air or water
- Indirectly via bioaccumulation/magnification
Impacts are chronic rather than acute
Concentrations are extremely low
